■■**■ (>08 z^5 THESIS Septoria petrosellnl van apli Causing Late Blight of Celery Oeorgre Lorenzo Zundel 1915 £60 S06 500 t'zei e Jjad E!Jo»das mim sjuauiuadxa u™"ui ALBERT R. MANN LIBRARY New York State Colleges OF Agriculture and Home Economics Cornell University XI Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924002905093 Infection Experiments with Septoria petroselini var, apii Causing Late Blight of Celery A MIMOR TIIESIS Presented to the Faculty of the Gradua,te School of Cornell University for the degree of MASTER OF SCIENCE IN AGRICULTURE "by George Lorenzo Zundel June, 1915 CX . Acknowledgement The work in tliis thesis was undertaken at the suggestion of Dr. A, W. Gillaert, and has been performed under his direc- tion. INTRODUGTIQH. It does not require technical knov;ledge for one to see the large amount of variation found in nature, extending in all fields of natural science. In the field of botany all plants vary in their requirements for food and not even the fungi are exceptions to this statement. In fact, in humid regions all plants, even the weeds have their parasites. The thought can be carried still farther, for even the parasites of our economic crops have parasites that in turn live upon them, A common example is the Darluca that is parasitic upon Puccinia, a common genus of our rusts. Every individual plant has certain inherent properties so that not all plants within a given species have the same power to resist the attacks of fungi. There are many phases to the power of host plants in resisting the attacks of fungi that cause disease or it is more properly called disease re- sistance in plants. The common nation is that any plant that is not diseased^ is disease resistant. Orton (1908) however points out that there are at least the following divisions (a) disease- escaping, (lo) disease-enduiting, (c) disease-resisting or immune varieties. By disease escaping is meant^that some characteristic of the plant or environmental factor pre- vented infection, as, for example, an early variety might mature teefore the season when the disease occurs so that it is not subjected to the conditions of infection, as are the 2. later varieties, or^tiirougii lack of moisture, proper oon- ditions for spore germination are not present so no infection A occurs. With disease enduring plants even fairly heavy attacks of disease seem not to injure them, as^ f or example, certain wheat varieties of the Dakotas and Minnesota seem to be able to withstand the usual attacks of rust. However, disease-resistant or immune varieties have the inherent power of preventing infection from any particular fungus. Immunity to one fungus does not infer immunity from all fungi that attacks that particular host plant. The production of disease resistant plants is a very promising field^ involving both plant breeding and plant pathology. Many diseases of economic plants cannot be con- trolled by the ordinary methods of spraying so that in many cases the production of immune varieties will determine the extent to v/hich certain industries will be carried on in tne future. To fully appreciate the significence of iimnune or even partially immune varieties one must understand the loss caused by some of the plant diseases. The following table partially compiled 'oy Reed will show this: ra cu CQ n -p H O +> Q) Ti m CD CO CD o CD -p s •H -P CD •H O -P CD CD O rH- 'Ki Q). -P CIS ■H -P CD o •H CD o •H (D CD Oj CD CD •H o Pi O H o • b « b • • • • • • rH 05 !>> c\3 U fH Jm ■ u in !h H ss oJ ^ Q) (D (D •• r C C fl c<3 o3 . c;3 , • S WOW ^ ^^ Qi lO o o o o o o o o to o o o o o o o o o o o 00' o 00 in H CD c: CD o H ^ H O O 3 -H ::j -rH ^ I -H I -H I -H ■P d -P S -p s CD 03 CD CO CD OJ ^ fH :3 fH pi ^1 K bOprJ bflprj bOfiJ -P 03 CL) ■P 00 rH 00 03 CO H 0) •H P< •H F£l iH 03 C , fH CC! +^ s CD U ^ CD •H 03 6 CD cii CD •H 03 u 0) •H 03 !H 0) CD ^1 •H 03 ■S ^1 CD C±! - lO cr> o o3 o3 •H -Ci o o3 r-{ •H -P CD 03 ■rJ -d M w OJ o lo o to o o o CO 0> O r-l CO CJ> CD 00 00 00 H H H •rl o •H O bO o3 H •H +3 CD J3 m 05 pi o b.0 oS H ■H -P 02 JU CO c3 CD CD (D CD CD CD CO CD cu OJ -P -P +^ 4J -P -P -p 4-> >i >^ 03 o3 CJ 03 o3 oS 03 '■^ rt pel O O o O O O O o 03 (U cS 0) CD •H o -p fl a H o 0) 03 02 03 O 0) -p a1 •H -P CQ -p u o o •H 'd o o o o o o o o 00 •H o o o o o o o to o I o CQ O o 03 ■H 03 O • • • S -p • r-l H Cl3 ^ H "* • H +i •H ■P ^« 03 C ^ ^ -p ^ • c •r* ^ H o o o o o o o o •* ^ ■> •» M m «« o o - o . in o o lO lO o ; « o lO cy> lO ; to C\J in w o o H O O CO o 03 03 03 0) •P -P 03 n5 cd -p +3 -H CO m ^1 'd 'd o 03 03 -H AH 03 +J -H ba -H •rt 03 -p +J •H -P S OH ;3 H -P -H O CO fn O rf Jh CO s fH •H 03 rH •H 03 03 03 H^ oJpc; 0) opu 03 Jhpc; ::J-ppVH SO ::! :3 o3 ft 03 rH -H ft 03 t^ 03 p o; pq p^■P h ^ c6 '^ o :r; r-\ 03 1 P ■H fi CO C ffl M to 03 CO t o3 1 03 O0303 03 ^'Q3H-P>iH 0} c o •P 03 i^ u 03 •H -P C -P G a3-P03-P g OHH-H O-H P' ?? H «n CS Ch rH +3 M • R :3 03 ;3 03 ■P >->^H -P O £h ft >>H 03 C3 ^00 ::5 03 tH 03 -p HJ ft-P U S !> g > 03 ,C! El -H H -; ftXl O H C^ u: W H fH K H •H :S o3 CQ <(; CO 03 Hi (Tin -H pq O u Hi CO fl| l> 03 03 03 03 03 03 o ra 03 D -p >» -P 03 c1 ^ ^ JH Pi 03 03 ; (S H^ H ^ H o ■P •P ■P ft^ ft , ^ OJ Ci3 rH f^ 03 03 o ft ft ,; 03 -H o O O p^ 4. ITATURE _OT DISE A SE-RESISTAITCB. The nature of disease-resistance is not well understood by investigators. Many attempts have been made to determine just why certain plants are resistant. There are three theories as to the cause of immunity in plants that are given most credence at the present time viz,-- A^ That resistance of plants is due to the nistological b structures of the host plant. B, That toxins and enzymes contained in the host plant render it immune. G. That disease resistance is a unit character and follows the laws of Mendel. As to the first theory, modern investigation has throvm a shadow of doubt. The thickness of the cuticle, the charactff of the foliage, whether pubescent or glabrous, size, shape and number of stoma might, in some cases, cause the plant to be disease-escaping but the susceptibility is the same as, for example, a glabrous leaf might dry sooner than one covered with hairs so that there is less opportunity for germination of spores and the pubescence would also tend to hold the spores on the leaf. After very careful researcii H. Marshall Ward (1902:323) came to the following conclusion. "The capacity for infection, or for resistance to infection, is independent of the anatomical structure of the leaf, and must depend on some other internal factor or factors in the plant," The second theory has no direct proof but several 5. prominent investigators have obtained results tliat indicate that some such, substances as a toxin or enzyme are responsible for non-infection. The subject is more complex than it seems at first. The fact that infection does not occur, does not say that the germ tube has not entered tne host. Ward (1890) Salmon (1905) and Stakman (1913) show that the spores of a fungus can germinate and even enter the host plant but there seems to be something within the host cell that prevents further development. The subject of parasitism is not well understood by investigators. The wide range in the relation between host and parasite is ^v»a?y phenomenal. The lowest form of parasitism is exhibited by such fungi that kill the host cell before feeding upon them, while the highest forms of parasitism are exliibited as symbiotic relationsnips. All gradations exist between the two extremes, Bunzel (1914) has recently found that there is a greater oxydase activity in the foliage and tubers of potato plants attaciCed by curley dwarf than, there is in the healthy plants. The tiiird theory was worked upon by Biff en (1907) in England, who found that so far as the yellow rust of wheat was concerned, immunity was a recessive unit character. So recessive was this character tha,t much difficulty was en- countered in raising his 1*1 hybrids, due to attacks from rust. That immunity acts the same for other plants remains to be shown. However, enough work has been done to show that* a certain plant that is immune in one locality is often the most susceptible when taken to another locality. Under present conditions it is hardly possible to say what is the exact nature of disease resistance in plants. However, results of the foremost investigators seem to indicate that the enzymatic- toxin theory and the unit character theory are the ones that most nearly explain the phenomena, REVIEW OP WORK ALREADY ACQ QIPLI SHED LM BREEDING DISEASE RESISTAI'TT STRAINS . Much remains to be done in breeding disease resistant strains of our cultivated plants. In many cases the disease is so easily controlled tnat it is not worth wnile to spend time in breeding resistant strains while there are many diseases that cannot be controlled except by this method. One big obstacle that is commonly met by workers in this field is that many of the most., resistant plants are of least commercial value. In this case hybridization is the only way to combine the desirable qualities in commercial and non-commercial plants. Many plants show natural resistance especially where the plant has existed longest. Ward (1902) says that the beginn- ing of all work in breeding for disease resistance is to go to the locality where the disease has existed longest and look for natural resistance of host plants. The work that has already 'oeen accomplished nas been ■wery valuable, a review of which follows. POTATOES . L.R. Jones and his co-workers at the Vermont Agricultural Experiment Station have done perhaps, the best 7. work on disease resistance in .potatoes. The late blight of potatoes caused by Phytophthora infestans causes much damage to the potato crops in America and Europe. Jones et al (1912) found in general that Surop^ean varieties were most resistant while American varieties were less resistant. The earliest attempts at breeding resistant strains was in 1876 when, with aid given by Parliajnent, the English breeders produced the resistant variety Magnum Bonum by crossing the American variety Early Rose with the English variety Victoria. Jones (1912) and his co-workers determined the rate of spread of the disease in resistant strains. The German variety Irene, the English variety Holoorn Ahundance and the American variety Ionia Seedling were used. A number of tiie plants of each variety were inoculated twenty times on twenty different leaves and the infected area was measured at intervals of two days It was found that the disease spread most rapidly in the non-resistant variety Ionia Seedling. At the end of twelve days the percentage of leaf area found diseased was as follows,- Ionia Seedling 58.98; Holborn Abundance 40,93; Irene 18.00. Many varieties were tested for resistance and each variety showed different powers of immunity. The English variety Royal Kidney was the most resistant while the Amer- ican variety Green Mountain was tne most susceptible, ASPiARAGUS , The very efficient work of J,B, Norton of the U. S.D. A, has saved the asparagus industry of the United States. The asparagus rust caused by Puccinia asparagi De G, was first found in New Jersey in 1906. It spread rapidly causing much 8. damage. Norton (1913) found that there v/as much variation in the plants in their relative susceptibility to the rust. By careful selection and self pollination he found that the power of resistance was inherited. Plant "Washington" A7-83 was found to "be the best breeding male plant in the rust resis- tant breeding work and a plant "Martha" B32-39 the best breed- ing female plant. From these two plants a superior strain of "commercially immune" plants w^ea?^ obtained. The new variety has been named the Martha Washington. SUGAR GANB . According to Lewton-Brain (1903) the best variety of sugar cane in the West Indies is the Bourbon. However, due to its susceptibility to the red rot disease caused by the fungus Golletotrichura falcatum Sacc it became practically impossible to grow this variety. The Caledonian Queen was introduced with other varieties and was found to be resistant but inferior in sugar production to the Bourbon, The Cheribon, a very good but susceptible variety, was crossed with the Chunnee, a resistant but inferior Indian cane, resulting in a good quality, resistant hybrid. Dr. Kobus has produced many good hybrids in Java. COPgES , Coffe arabica is the coffee with tne highest quality. It is, hov/ever, subject to a leaf-spot caused by Hemileia viastatrix Berk, et Br. This disease tnreatened to make the growing of coffee impossiole in Arabia and Ceylon. According to Lewton-Brain (1903) the Goffea liberica was found to be more resistant, more productive with a larger berry but of inferior flavor. In a recent lecture at Cornell 9. University Lr. Otto Appel said that tlie fungus had adapted its self to Coffea liberica which was now very susceptible so that wild coffee, Coffea robusta, of central Africa, was found to be very resistant and is largely grown now. This last named variety is of a poorer flavor than C. liberica. Lewton-Brain reports (1903) that M, Henri Manes has hybrid- ized Coffea arabica with Coffea liberica and has a hybrid plant with the good qualities of the parent plants combined, COW PEA . (Vigna sinensis). The cow pea is a f,orage crop grown largely in the southern part of the United States. The plant is attacked by a wilt disease caused by Fusariuni tracheiphilium Erw. Sm, In 1902 Orton and Webber began working to obtain a disease resistant strain. Orton (1911) states that they found all the varieties that The Gardeners' Chronicle (March 6, 1910, p. 153) says: A.new species discovered growing wild on the shores of the Oubanghi, Central Africa, by Mr. Dyboneski, and named C. congensis, which has been grown since 1903 in the botanical garden at Ivoloina, has so far remained free from disease (Hemileia), Its market value is said to be fully equal to that of the best qualities of Arabian coffee. While the present crop of C. congensis has not suffered from the disease, C. arabica, planted at the s^ne time, has been en- tirely destroyed. 10. were tested, suscepti"ble. However, they had their attention called to a cow-pea that was cultivated in a limited area in South Carolina which was called the Iron Cowpea, This variety proved to be resistant but inferior in yielding quality. Through the work of Mr. Gilbert of the U. S. Dept, of Agr. a cross between the Iron variety and Whippowill has resulted in a high yielding, good quality, disease resisting strain. It might be well to state here that in this series of crosses the/\generation (Iron x IIHiippov/ill) wer^ resistant and re- sistance was found to be a dominant character. CQTTOH. There are at least two species of cotton culti- vated in the Southern States, Gossypium hirsutum and Gossypium Gossypium barbadence. Both species are subject to cotton wilt caused by the fungus Ueocosmospora vasinfecta (Atk. ) Erw. Sm. and also the bacterial blight caused by Bacterium malvacearum Erw. Sm. Orton of the U.S. Dept. of Agr. did the first work on wilt resistant cotton. He says (1911) that all the varieties were very susceptible to the disease. However, in large plantations a few occasional plants were not wilted either because they had escaped infection or were naturally re- sistant. It was found that the natural resis-tance was in- herited so that by straight selection disease resistant strains v^rere obtained. The Dillon and Dixie were two of the +The I'ron-cow-pea is, however susceptible to attacks from leaf spot caused by^ Amerosporium oeconomicum and Milde?/ caused by Erysiphe polygoni. On the other hand it is resistant to rust caused by Uromyces appendiculatus (Pus) Link, and a leaf-spot caused by Cercospora cruenta. , 11. varieties while the Modella was developed by A. C. Lewis and the Rivers variety developed by E. L. Rivers of James Island, South Carolina. The Centerville is a variety selected by Orton from the Rivers wnich is resistant to the wilt and also to the bacterial blight. WATBR- - MELLQIfe (Citrullus valgaris.) The water melon in the Southern, and Pacific coast states is subject to epiphy- tatics of the wilt disease due to the fungus Eusarium niveun Erw. Sm. Orton (1911) referring to his work in producing a wilt resistant water melon says that all varieties of the 120 or more tested were very susceptible. However, the inedible form known as "citron" or" stock water melon"' was very resistant. A cross with the citron as the male parent with the excellent commercial variety Eden as the female parent resulted in having most of the citron char- acters dominant in the hybrids. Out of the ten possible chances from 5,000 plants, eight were found undesirable, so that of the two which were pollinated fror.i the Eden, promise ing; results were obtained. However, the progeny of these two plants- varied much, all kinds of shapes, colors and flav/ors were represented, FxY/e yeaars selection resulted in the high- ly resistant strain .but some what inferior in quality, known as the donqueroE, This^ strain proved highly resistant in Iowa- but was not maJrHrfe-arit red ■ whe^-grtywn in Oregon on the Pacific; coast. This, is but one proof of the need of breed- ing for certain local conditions only. 12. WHEAT . Biffin (1907) reports the loss of wheat due to rusts during 1891 in Prussia as ^[^ 20, 600, 000 or a"bout 2/3 of the crop. lie Alpin is quoted as reporting that is Australia, J;^100,000,C00 does not cover the annual loss due to rusts. By means of hyl^ridization Biffin (1905), in England produced a rust resisting wheat. He found that resistance was a recess- ive character. Howard (1907) reports that when Biffin's immune v/heats were grown outside of their original conditions some b-^oaitte very susceptible. Farrsr (1898) reports some progress in gettin^:; immune varieties of wheat for Australian conditions while Pole-Evans (1911) gives as his opinion that hybrids seem to be bridges by which the rust is carried from the susceptible to immune varieties. Butler (1905) reports rust-resistant work being done for India conditions. RED GLOVER . (Triiolium spp. ) The red clover in and about Tennessee is attacked by an anthracnose caused by the fungus ColletBtricuim trifolii Bain. By careful selection Bain and Essary - (1907) of the Tennessee Agr. Exp. Station developed a resistant strain of *red clover. They report that the odds in favor of the selected plants for non-resistance is 50 to 1. TOBACCO . (Hicotianum Tabacum L. ) Jackson (1908) reports that by selection, Sharael and Gobey have obtained a tobacco in Connecticut resistant to the wilt caused by Bacillus solanace- arum Erw. Sm. Eavorable results have also been obtained in iTorth Carolina for a similar disease. 13. CA17TAL0UPE . Blinn (1905) of the Colorado Agr. Exp. Station hy careful selection has developed a variety rssiatant to the leaf blight caused 'by the fungus Macrosporium cucumer- iniun Ellis and Everhart. VIOIiBT. Lewton-Bnain (1914) estimates that the violet crop in the United States is worth one million dollars and that 200,000 worth of damage is caused each year "by the violet leaf-spot caused by the fungus Alternaria violae Galloway and Dorsitt. Investigation has shown that varieties differ in their susceptibility. The variety "Maria Louise" is very resistant but does not produce such perfect flowers as the more susceptable variety "Lady HiAme Campbell. (See U. S.D. ADW. Phy. and Path. Bui. 23 1900) GRAPE . It is a well known fact that European grapes cannot oe grown in the Eastern United States due to their susceptibility to Phylloxera and downy mildew caused by Plasmopara viticola. The subject is too well known to take more space at this time. PLAX. Bolley (1908) has made great progress at the North Dakota Agr. Exp. Station in breeding strains of fla,x resistant to wilt caused by Pusarium lini Bolley and rust caused by Milarapsora lini (DC) Tul. He succeeded in getting his resistant strain by selecting a few sickly plants^that had not been entirely killed in a field badly infected with wilt. By planting the seed from these plants on badly infested ground and continually selecting the best plants for a few years, he at last obtained his resistant strain. 14 ROSES MP SAMD CHERRIES .' Hansen (1905) of the Soutii Dakota Agr. Exp. Station, by continuous selection has obtained strains of the Western Sand Cherry (Prunus Besseyi) which are A resistant to mildew caused by the fungus ,'§ip aero thee a pannosa (Wallar) Lev, He finds that glossiness of leaves is correlated with disease resistance. By crossing the cultivated Hybrid Perpetual roses with a hardy prairie rose, ^ a sttain resistant to dowdery mildew caus- ed liy the fungus Sphari,otheca pannosa (Wallr) Lei. CHERRY . Salmon (1906) working at Wye, England noticed that Waterloo 'Sherries were badly infected with cherry leaf scorch caused by the fungus Gnomonia erythrostoma Anersv/. while alter- nate rows of the^turks cherry were not damaged. CARROT . Halsted (1897) found that varieties of carrots differed in their susceptibility to the blight caused by Rhizoctonia (?) In order of resistance the test showed Danver' s Half Long most resistant with Long Orange, Early, Half Long Carentatn and Long white Belgian next in order. Plate I. A Wild Celery Plant (after Gerard, 1597) 15. The History of Celery. Tlie speculation as to what might have been the case had America "been the home of modern civilisation and Colurn'ous had sailed east, resulting in the British Isles being discovered seems interesting guess v/ork. Nodou'bt our modern seed cata- logues would have contained many new species derived from native plants. Most of our modern vegetables are of European or Asiatic origin. Although many of them have been known for many years, yet, have not been extensively cultivated until recently. Celery has been known to mankind under one name or another ssince early Grecian times. It was spoken of 'oy Homer and Theophrastus under the name of Selinori, and later Dioscorides distinguishes between the wild and cultivated forms. However, Pilny the Elder in his "Pleasures of the Garden" does not mention celery although several vegetables coimaon at that time are mentioned, De. Sturtevant say'd that the first mention of the word celery that he dan find is in V/alafridus Straba's poem entitled "Hortulus" which was written in the ninth century. The medical properties of celery are given and in line 335 the following sentence appears; "Passio turn celeri credit deviota medelae," and then gives the translation to be "The disease then tis^'-celery yields, conquered by the remedy. " Dr. Sturtevant further states that he cannot find celery mentioned in Puchsuis (1542) Tragus (1552) Matthiolas Commentaries (1558) Camerarius Epitome (1558), Pinnarus (1561), Pena and Lobel (1570), Gerarde (1597), Glusius (1601), Dedonacius pempt. ^1629,) 16. In searching through the old "Herballs" and other old agricultural writings in Cornell University Library the first mention of celery was by Dodoeus (1578) in the "ITierve Herball". It is spoken of under an old Greek name Elioselinon and the follTJwing names are given; "Greke- Latin- Apium pa.lustre, Paludapium called by some Hydroselinon agrio In shoppes- Apium etc. Dodoeus' work contains many good pictures of the various forms of Apium. About 1633or 1636 Gerarde and Johnson in their revised edition of "The Herball or Generall Piistorie of Plants" mention Eleoselinum or Paludopium and writes that it "Grows in moist places from v/hich place it is brought into gardens". Grows abundantly upon banks of salt marshes of Kent and Essex". The names are about the same as those given by Dodoeus. The Gaza name is given as Paludapium. Much in fact, most of the is space given to a discussion of the virtues among which are the following; It is good for long lasting agues and yellow jaundice. The juice cures "venomous ulcers of the mouth" and mixed viith honey is good for cankers, Pliny writes that it is good for bites of venomous spiders, etc. Parkinson (-1640 Theatrura Botanicum) speaks of two kinds of celery as follows: "1. Bleoselinoia , Paludapium sive Apium palustre , Smallage. 2. SeliniAm Sive Apium dulce, Sweete Selium or Smallage, familiar in Greece and Italy where it is eaten" Ivleager (1688) includes smallage or celery in his list of "Physick Herbs, usually planted in Gardens." Selery in its wild state has a very pungent tast which is changed "by cultivation. De Condolle gives the habitat of celery as being from, Sweden, through central and western Europe and along the Mediterianean to Greece and Turkey, As has oeen shown the ancients used celery primarily as a medical herb and the Italians seem to be the first people to have used celery as food. Miller (1757) gives the first classification of the genus Apium using the form of nomenclature common before the time of Linneus. Of the genus Apium he says under the head- ing of "Celery, or Salary, vida Apium" , -"Apium (Apium is so called, as many say, of Apes, 3ees, because Bees are said to be delighted very muah with it; or of Apex, because the Ancients made Crowns of it to adorn the liead". ) To the six- th sort is given the name Eleoseninum which comes from two Greek words meaning Marsh-Parsley. The work Parsley is more common about this period and thirteen species are mentioned as follows: "1. Apium hortense sen petroseliuum, vulgo. C.B.P. Common Garden Parsley 2, Apium vel petroselinum crispum C.B.P. Curled Parsley. 3, Apium hortense latifolium. C.B.P, Broad leav'd Garden Parsley. 4, Apiivira Lusitanicium rotumdif olium . Inst ,: R. H. Round leav'd Portugal Parsley. 18, 5. Apiiim hortense latifolium, maxima, crosslssima , suave , and eduli radice Brerh . Broad-leaved Garden Parsley, with a large seet, edible root. 6. Apium Palustre , and Apium off icinarum , G.B. P. Smallage 7. Apium dulce , Celeri Italorum, H.R. Par. Celery. 8. Apium dulce, degener , radice rapocea Jussien . Turnit-rooted Celery, commonly call'd Celeriac. 9. Apium Macedonioum G.B. P. The Macedonian Parsley. 10, Apium Lusitanicum maximum, f o^io trilobata, flore luteolo, Brerh. Ind. Great Portugal Parsley with a trilobated Leaf, and a yellowish Flower. 11, Apium Pyrenarcum , thapsi ae facie, Inst . R. H. P yr enean .Par s 1 ey , with the Pace of the Deadly Carrot. 12, Apium montanum , sive petrafeum alhum J. B. Rail White ■'''fountain Parsley. 13, Apium montanum, sive petraeum album Elatuis, Taller White Mountain Parsley." That celery was cultivated at tnis time is shown by the fact that directions for grov/ing the crop and hilling up the plants are given and the conclusion is that celery. "Will not keep over 3 to 4 weeks after blanching." Smallage is spoken 19. of as a weed, the seed of which is used as medicine. That some of the species given were mere variations seems to be upheld hy the fact that Miller in his 8th edition of "The Gardeners Dictionary" (1768) follows the Linnean classification and only gives seven species as follows: "1, Apium (Petroselinum) common Parsley 2, Apium (Crispum) Curled Parsley 3. Apium (Latifolium) The large rooted Parsley 4. Apium (Graveolens) Smallage 5, Apium (Dulce) Upright Celery or (Apium dulce dulce celeri Italorum) 6, Apiiim (Rapaceura) Celeriack 7. Apium (Lusitanicum) Celeriack Miller then critisizes Linnaeus for putting celery in species , with smallage, supposing the only difference to be due to cultivation. It is maintained that Smallage and Celery are different. From forty years experience in culti- vating smallage. Miller cound not bring it to "the same good- ness as Celery" the only changes was "a larger size" but not so tall as Celery, Smallage sends out many suckers from the root and will not "rise with a straight stem but can be blanched by earthing up. Physicians mean smallage when Apium is prescribed. " Prom studying the descriptions of the modern varieties of celery and comp,aring them with the descriptions of Miller, Gerarde, and other early herbalists it seems to indicate that 20. our modern Celery originated from several varieties and it is very probable that tixe different peoples iiad reached differ- ent stages in the culture of the crop and then again^ since Celery is prone to excessive variation that might have made matters more complex. The first mention of varieties is by Mawe (1778) under Apium dulc, two varieties being mentioned, the Hollo\v Celery and the Solid Celery, The Hollow Celery is spoken of as the original variety and was known long before the Solid Celery, One thing that impresses its self in this early article by Mawe is the complete cultural methods given for growing Celery and also, in his earlier work (1765) Celery is spoken of as . good for soup, Abercombie in (1786) mentions three varieties of Celery, 1, Common upright, 2. Solid stalked upright, 3, Giant upright and a fourth Celeriac, or dwarf turnep-rooted Celery is given. Later Abercombie X,1'79'?) in discussing the subject says "Apium graveoleus or Smallage is a common weed, bearing great resemblance to Celery, insomuch that the latter is by some supposed to be a variety of the former, raised to its present state of perfection by long culture;but I greatly doubt this; since both sorts retain their difference from seed. " It is further stated that it is the smallage that is used for medicine and only used for culinary purposes hj poor country people who use it for broth ar potage, Abercombie classifies common Celery as Apium dulc and mentions three kinds viz, 1. Hollow Celery, the original variety, 2. A solid kinji, but it is not recommended as it will not endure as well as the 21. hollow kind and 3. a giant kind which is good for autumn or early winter. Previous to this period no mention of a named variety of celery could "be found, however, in 1805 Abercombie speaks of the common upright celery as the Italian. About this time celery culture had also begun in the United States. Mi^Mahan (1806) a nurseryman and florist of Philadelphia puts celery under the following heads,- 1, Common upright with hollow stalks, 2. Italian or upright, 3. Solid stalked Celery, 4, red-stalked solid eelery. This is the first mention of a red variety and whether the red or white sorts were the original could not be determined, Not much progress was made the next twenty years for in 1829 Mawe gives almost the iden- tical list of varieties of Celery as was given by Abercorabie (1805) and M Mahon (1806). However, interest was beginning to be aroused and in 1841 the first classification of Celery is given in the Gardener's Chronicle as follows: 1. Violet, solid, with a violet tinge where the stalks are exposed to the light but blanching to very pure white, and of delicate flavor. Th^ Manchester celery appears to be only a strong- er grov;ing variety of this. Flavor not so good. 2, Turc, a white solid autumn celery. 3, New Flat Stemmed White Solid, very large and solid. r' Best white celery, 4. Seymour's Supurb V/hite Celery, This celery is mention- ed on page 113 and the reader is referred to the London Magazine for F eb, 1841 for fuller 22. description. 5. (White Solid and Manchester Red, recommended for home garden) The cultivation and production of new varieties must have been stimulated about this period as shown by the large number of synonyms found in the classification of 1850 given in Gardner's Chronicle, viz,- Celery. The varieties of celery may be divided into two classes, - A. White Celery B. Red Celery. The hollow stalk celery known as Common Red and Common White is no longer worthy of notice and ought to be excluded from cultivation, A. White Solid. White Solid, alias Fine White Solid, Celeri Turc, Geleri plein blanc. 1. SEYMOUR'S SUPERB WHITE, Italian, alias Italian Upright, Upright, Large Upright, Giant, Patagonian. Curled White, alias Nain frise. Leaves resem- ble parsley Wall's ¥/hite, (syn) Imp. Italian, 2. EARLEY DWARD SOLID WHITE, alias Court hatif , Celeri Turc of some. 23. B. Red Solid 3. RED SOLID, alias New large Red, l-Tew Large Purple, New Russian, Cole's Red, Cole's Superb Solid, Violet de Tours, Gros Violet de Tours, Even in 1853 the authors of agricultural books had not given up the old method of classification for in that year Johnson gives the varieties as follows: 1, Gigantic dward curled 2, Common upright red stalked 3, Upright giant 4, Hollow upright 5, Solid stalked (red and v^rhite) He then adds that reds are for^soups while the white are of more delicate flavor. Progress is shown in that the follow- ing named varieties are given, viz,- Violet; Turc; Cole's superb (red and white) and Nutt's Champion. The latter variety is said to be the "best. ■ In 1876 the Royal Horticultural Society made a celery test which was reported by A. P. Brovm in G-ardeners Chronicle p. 106 CLASSIFICATIOIT OF CELERY FROM TESTS MADE BY TPIE VEGETABLE COMMITTEE OF THE ROYAL HORTICULTURAL SOCIETY, MADE AT CHIS^ WHIK, IROM SEED OBTAIIOJD FR03/. 10 ENGLISH SEEDSMEN AND VILMORIN et CIE OF FRANCE. 1. Red Varieties. 1. Mammoth Red, (syn. Laig's Mammoth, Radford's Pink, Sulham Prize Pink, Hooley's Conqueror Prize, True 24. Manchester Giant Red, ) 2. Ivery's Nonsuch, (syn. Violet de Tours, Osborn's Selected Red, London Market Red. ) 3. Kiaberley's Red, (syn. Imperial Solid Red, Stuart and Mein's Red. ) 4. Carter's Incomparable Crimson, syn. Carter's Incomparable Dwarf Crimson, Hood's Dwarf Red.) 5. Webster's No. 1, (syn. Webster's No. 4.) 6. Leicester Red, (Major Cla,rk's Solid Red, Turnmoss Red, Ramsey's Solid Red. ) 7. Wright's Improved Grove ited, (no Syn. ) 2. White Varieties. 8. Grove White, 9. Incomparable Dwarf White, (syn. Plein Blanc Court Hatif, Sandringham, Dean's Compact White.) 10. Plein Blanc, 11. A Coupler, 12. Turc Grand, 13. Seymour's White, (syn. Goodwin's White, Northumberland Champion \¥hite. ) 14. Prize-taker ¥;hite, (syn. Veitche's Silver White.) 15. Dixon's Mammoth \¥hite. 16. Great Eastern. 17. HaywoocJs White Q,ueen, (syn. Stuart and Mein's Giant White, Gooaall's Flat-stalked, Webster's White.) 18. Veitche's Solid '«iite, (syn Dane sbury. ) 19. Boston Market. 25. 20, Prise, Curled or Garnishing Celery. 21. Turnip-rooted, (syn. Celeri" llavet, Rave, Have d'Erfurt, Soup Celery. ) Much controversy arose over this classification and many growers o"bj acted having their varieties of celery placed as synonyms. So strong were some of the olojections that even as late as 1884 the Gardener's Chronicle printed objections sent in by celery growers. Up to about 1883 all celery was blanched by hilling up soil around the plants. About this tima a new variety of celeyy was introduced that was destined to revolutionize the celery industry of America, At Issy, near Paris, France there appeared a sport in the celery patches of a Mr. M. Chemin in 1883. The next year Jas. Vicks and Sons introduced this celery into America. It was called Chemin' s Celery, or White Celery and at present is known as Paris Golden-Self Blanching. In 1884 Peter Henderson and Co. introduced the White Plume celery which was a sport from Half Dwarf and originated in Hender- son's trial grounds in New Jersey. In 1885 Henderson' sNev/ Rose Celery was introduced. The Hew Hose and Giant Pascal in 1892 and the New Pink Plume in 1894 are some introductions by Peter Henderson and Co. After about 1885 celery culture was stimulat- ed in America. The introduction of Golden Self-Blanching and Henderson's White Plume gave two excellent summer celeries to the markets, and the Giant Pascal is a leading winter variety, while the Boston Market retains its commercial importance even with these modern additions. 26. No "breec.ing of celery has been done. The plant is very easy to produce variations and "by selection the modern varieties have "been produced. The Royal Horticultural Classification of 1893 shows many changes from the one in 1876, Jour. Roy. Hort. Soc. 16:250-251. Celeries admit of division into three classes, viz: Class 1, White varieties. Class 2. Red varieties. Class 3. Celeriac. Class 1. V/hite Celeries. 1. White Plume (Messrs. ^lilmorin et Cie. )Plants dward. Outer leaves pale green, the younger or heart leaves pale silvery white, as if blanched. Hearts small, not very firm, of inferior quality, but very ornamental, and suita'ble for garnishing. Plant somewhat tender, 2. White Plume (Messts P. Henderson and Go. ) Same as No. 1, but of taller and stronger stock, 3. Paris Golden Yellom' (Messrs "Vilmorin et Cie. ) Plants dwarf, stocks thick and "broad. Hea,rts large, firm, and solid. 4. Henderson's Golden Dv/arf (Messrs. P. Henderson and Co.) Stock mixed. inferior to No. 3. 5. Sandringham White (Messrs. J. Veitch and Go. ) Plant dwarf. Hearts firm, solid white, 6, Sutton's White Gem (Messrs, Sutton and Sons. )A very dwarf stock of No. 5. 27 7. Henderson's Half Dwaxf (Messrs, P. Henderson and Co.) Of taller and stronger growth than No. 5. 8. Dwarf Large-ribToed Ytoite (iiessrs. Vilmorin et Gie. ) A late variety. A very broad-stalked variety, with solid hearts. 9. 7/hite Solid Pascal (Messrs. Vilmorin et Gie. ) Stock mixEd and irregular. 10. V/right's Giant White (Messrs J. Veitch and Sons.) Plants of moderate height. Hearts large and solid.' 11. Do"bbie's Invincible White (Messrs. Dobbie and Go.) Plants tall. Hearts firm and solid, and of good quality. Glass II. Red Celeries. 12. ITew Dwarf ^Red (Messrs. J. Veitch and Sons. ) Plants dwarf and compact in growth. Hearts of moderate size, firm and solid. 13. Sutton's Al (Messrs. Sutton and Sons.) Similar to Ho. 12 14. Improved Purple (Messrs. Vilmorin et Gie. ) Plant dwarf. Keats firm and solid. Stock somewhat mixed. 15. Carter's Standard Bearer (Messrs. Carter and Go.) Plants tall. Leaves broad, deep green. Hearts firm and solid, and very hardy. r 16. Veitch' s Early Rose (Messrs. J. Veitch and Sons.) Tall growing. The stalks rounded, firm crisp, and solid. Early. 17. Ivery's Nonsuch (Messrs. J. Veitch and Sons.) Tall growing Leaf -stalks broadly ribbed. Hearts pale, large and solid. 28. 18. Carter's Solid Ivory (Messrs. J. Garter and Co.) Similar to No. 17. 19. Standard Bearer (Messrs. J". Veitch and Sons. ) Tall growth. Heads large, solid, deeply coloured. 20. Bobbie's Select Red (Messrs Bobbie and Co.) Tall growth Stalks broadly ribbed. Hearts large, very solid and good. 21. Major Clarke's Solid Red (Messrs, J. Veitch and Sons.) Plants of compact, medium growth. Leaves deep green, deeply serrated. Hearts very firm and solid. Excellent for early use. 22. Hartshorn (Messrs. Vilmorin et Cie. ) Dwarf. Leaves deepl5i toothed and lobed, shining green, 23. Large Smooth Prague (Messrs. Vilmorin et Cie. ) Plants of tall growth. Bulbs large. 24. Variegated (Messrs. Vilmorin et Cie. ) Plants small. The leaves prettily variegated with white. The very early varieties were produced by the gardeners of the big estates in England. In fact about 1750 celery was con- sidered a luxury for the tables of lords and others of rank. In concluding this brief history it might be well to give a list of men that have contributed in making celery culture • \ ' what it is to-day. Jas. Waters (1855) the Rectory, Penshaw, Fence House, Durham was one of the early cultivators. Also Samuel Jas. Patshull of Ullrighton, f/olvertonhampton^ G. Adams and Son, Domino Cross ITursery, East Retford in 1859 introduced the 29. • Monarcli Celery. Celery shows are mentioned as early as 1866 and Mr. John Cox was a leafing exhibitor. In 1867 Hooley's Conqueror Celery was first shown" hy the originator, Mr. S. Hooley, a mechanic of Nottingham wtio obtained his strain by careful selection f©r a number of years. Alexander Ingram, of Alnwick Castle Garden was a leading judge about 1875 at the celery shows around Nottingham which is a big English celeey centre. At a celery show in Carlton Nottingham in 1869 there were tv/enty eight exhibitors. Other English seedsmen that have helped to develop celery are;- Chas. V/. Breadmore, ¥/inchester; William Bull, Chelsea, London, S. W. ; Jas. Garaway and Co; Daniels Brothers, Limited, Norwich; J. Veitch and Sons; Sutton and Sons; Dobbie and Cc; In Erance Vilmorin Andrieux et Cie have done much for celery culture. In America Peter Henderson, C. C. Morse and Co. , D. M. Eerry and Co. , Vaughn Seed Co, , W. A. Burpee, Jos Breck and Sons with many others could be mentioned. It was the early English varieties of celery that were introduced into America,, The Country Gentleman for 1859 gives an account of the introduction of Cole's Chrystal White celery, A Mr, E. A, Elemming of Curwensville Clearfield ico. , Pa. re- ports that it was introduced into the United States through the U. S, Patent office. In 1860 Mr. Elemming mentions the Solid White celei^y and the Country Gentleman for 1874 reports Dwarf Incomparable as the most popular variety in New York. In 1853 the same paper speaks of the New Red .Celery and in the same 30. year a gentleman signing as W. G. S, Prom Romulus, Seneca Co. , H, Y. reports their success with celery on Mt. Airy Parm. Mr. W. P. S. says that celery is indiginous to America and grov;s luxuriantly along the shorew of the Potomac and James rivers, The Chesepeake Bay and the Coast farther south. He attriToutfes the good flavor of the Canvas Taack duck to the fact that they live on wild celery during the vdnter. While atout one new variety of celery has been introduced each year for the last century yet they are more or less related. Throughtthe kindness of Prof. U, P. Hedrick of the New- York State Experiment Station, Geneva, i7. Y. , the celery notes of the late Dr. Stnrtevant were made available, by the aid of which the writer was able to get the history of the Golden Self Blanching celery of the Chemin and also its relatives. The Golden Self Blanching celery originated near Paris from the Sandringham celery which was much cultivated at Sand- ringham, England, and said to have originated in the garden of the Prince of Wales, The Boston Market is spoken of as being closely allied to the Sandringham except that it is taller and given more to suckering. Vilmorin speaks of the Boston Market celery as being closely allied to Dwarf White Solid, and trials at Geneva 11, Y. showed the foliage of Crawford's Half Dwarf White to be not perceptibly different from Boston Market and th@ -Crawford's Half Dwarf is closely related to Early Dwarf Solid White and 31. Henderson's Half Dwarf from which originated Henderson's V/hite Plume. Again New Solden Half Dwarf is related to Boston Market, as is also the Early Arlington. The Solid Ivory is similar to Sandringham but "blanching perfectly white. Here is a case of another celery originating from Sandringham before the Golden Self Blanching of Ghemin. The Giant White Solid is related to Boston Market. Dr. Sturtevant gives the following as probable synonyms of Sandringham; Dwarf White Solid, Henderson's Dwarf White, Incomparable, Incomparable dwarf White, Sandringham Dwarf White and Turner's Dwarf White. The 5'ollowing diagram v/ill probably tend to make clear the relationships given above; Wild celery Italian I Upright White! Solid Giant ^Ihite Solid Boston Market Early Arlington New Golden Half Dwarf Dwarf White Solid 1. Sandringham. Gi*awford's Half Dwarf Henderson's Half Dwarf Solid Ivory Golden Self Blanching Columbia (19Q6) Probable Ancestry of Red Qelery. Red Solid of Violet New Large Red Col^s Red Cole's SuTPerb White Manchester Celery 32 Henderson's Rose liTew Rose Dwarf Under Major Clark's Solid Red celery, Dr. Sturtevant puts as synonyms,- Wiseor's Durham Ked, Ramsey's Solid Red, Turm or Red. Vilmorin describes the plant as vigorous, almost of the size of London Market Red, 'but the foliage is more bushy and of a deeper green. The diagrams do not represent in each case exact origins of the varieties hut prohahle relationships as sho^im hy Dr. Sturtevants' work at Geneva, W. Y. and also by the aid of other literature. The classification at least shows the many small variations that arise by subjecting a plant to different cultural conditions and each cultivator- with a different ideal. In other cases varieties are mutations. The Columbia is a mutation of the Golden Self Blanching, having been found in a celery field in Ohio. It was introduced uy D, M. Jerry and Co. in 1906, EXPERIMENTAL. The object of the present experiment was to make a pre- liminary test of the relative susceptibility of different varieties of celery to the late blight disease or leaf spot caused by the fungus Septoria petroselini Desm. var. Apii 3r. and Gav. This fungus caused very heavy losses to celery grow- ers. It is reported by the California Agricultural Experiment Station that in 1908 the loss to the California celery grow- ers amounted to 1950 car loads or a money loss of 550,000. 33. Klebahn reports that due to tiiis disease in certain parts of Germany celery culture iias become almost extinct. The value of a variety of celery immune or even partially immune to the fungus would therefore be of great value to European and Amer- ican celery growers. l^ETHODS USED IN THE EXPERIMEITT. The seed of forty three varieties and strains, previously obtained from the Vegetable Garden Department of Cornell Univer- sity, was planted in a rich sandy soil, June 17, 1914, in ordinary flats. The flats were covered with glass and kept in the Plant Breeding greenhouse. The seedlings received the same kind of care as ardinary commercial seedlings. On July 17, the seedlings \vere transplanted into flats containing a rich soil prepared by the Vegetable Gardening Department and were pricked out 1 1/2 x 1 1/2 inches. The plants were then put out in a cold frame and exposed to ordinary weather con- ditions. August 17, the seedlings were planted into 6 inch flower pots containing a rich sandy loam. One plant was put into each pot. At this point in the work it was found impossible to use all the 43 varieties and strains so 13 of the best commer- cial sorts were selected. Sixteen plants each of eleven var- ieties and eight plants each of two varieties were used. The plants were then kept in the south end of the Plant Breeding ;^reenhouse and watered every day or two by sprinkling. About October 1, the plants were inoculated with spores of the Septoria fungus as follows:- S4. The source of the material v;as from three badly infected plants sent to the writer by Mr. Henry Griffrath of South Lima, N. Y. , President of the IT. Y. Vegetable Growers Assn, By plac- ing pieces of the leaves infected with ripe pycnidia into water the spores ooze out and by squeezing the wet leaveB-,,more spores are forced out. This water containing spores was then strained through one thickness of cheese cloth into an atomizer. Each variety had previously been given a number and in order to eliminate, as far as possible, the possibility of previ ous conceived ideas of the relative suscerjtibility of the different varieties, the numbers were used entirely. The plants were divided into series for innoculation and named A. B. G. and D. This Vi^as necessary due to the fact that the inoculating chambet of the Plant Pathology Department could not hold all of the plants at once. Series A. contained 5 plants taken at random from each variety. Series B. contained 4 plants of each variety Series C. contained 5 plants of each variety Series D. contained 4 plants of each variety The only exceptions were the two varieties in which only 8 planfe plants were used a,nd they were inoculated as follows; Series A. - 3 plants Series B, ~ 5 plants The plants were then placed in the large glass inoculating chamber in the Plant Pathology greenhouse. This chamber is equipped to furnish air saturated with moisture Just before the plants were put into the inoculating 35. chamber they v/ere sprayed v/ith water from an atomizer until the plantfwas thoroughly covered with droplets of water. They were then sprayed with the water from a second atomizer con- taining spores. In order to get as even an inoculation as possible each plant received four long sprays from the second atomizer by pressing the bulb of the atomizer four times. The plants were left in the inoculating chamber from 24 to 48 hours. Previous tests showed that in 24 hours there w^as -- nearljr 100.^^ germination and in 48 hours there was a germ tube formed about twice as long as the spore. After inocluation the plants were taken back to their original place in the Plant Breeding greenhouse and in from 3 to 4 weeks infection appeared It might be well to state here that the writer realizes that it is not possible to v^et equal inoculation by using the atomizer as one is not sure that the same number of spores are placed on each plant. Hovirever, no other bettwe way was known METHOD OP COMPARING RELATIVE AMOUNT Off INFECTION ON EACH VARIETY. V/hen it was found, that the disease had reached its maxi- mum, the leaf area and number of spots on each plant were calculated and also the number of spots per square decimeter of leaf surface were calculated. This was done as follov^s: Por series A. and B. an apj3,aratus on a drawing table was arranged so that the plant could be tipped on its side and the 36, area of ten representati-toe leaves was measured with a plainl- miter. The number of leaves on the plant were counted and from this data, the leaf area of the plant was calculated as follows: Example. No. of leaves on plant 46 Leaf area of 10 leaves 350 sq. cm. Average area of each leaf ..,.35 sq. cm. Total area of plant 46 x 35 = 1610 sq. cm. The total number of spots was counted on each |ilant. This was done with an ordinary watch counter. If there were 437 spots on the plant, the number of spots per square decimeter of leaf surface was found as follows: ^^2 X 100 = 27.12 spots per sq. deem, of leaf surface; 1610 or to convert this to a mathematical formula, let B= total number of spots on plant and A^ tota,l leaf area of plant in sq. cm. D= no of spots per sq. deem. Thus ; 100 ^ = ^' RESULTS. • It must be kept in mind that the results are only pre- liminary since the experiment was carried through only once. However, the follov/ing facts are brought out very forceably. In the first place the different varieties showed diff- erences in their relative susceptibilities to the disease. The number of spots cannot always be taken as a basis to es- timate immunity, i.e. according to Plate V. the curve Bhows 37. that No. 11, va,riety White Pliime, is high in immunity, however, *,'nile there were few spots they were very large and tended to cover the whole leaf surface. The photograph Plate XVIII. also shows the susceptibility of this variety. On the contrary, the curve in Plate XIV. shows that No. 23 or French's Success, to "be relatively immune and very few infection spots were found on this variety. This is very well shown in Plate VIII. giving the graphic results of this variety} and also in the photograph Plate XX. Other varieties as No, 17, Giant Pascal, and No, 29, New Rose, had a very large numloer of small infection spots from the size of lead in a lead pencil to the size of the end of a lead pencil. Aside from the foregoing observations there are at least two facts that a,re of primary importance. The first is the pronounced individuality of each plant. This is very well shov/n by the tables X to IV. and also in plates II. to XIV. Por instance note the great variability of variety No. i, Golden S elf Blanching, plate II. One individ- ual has nearly 120 infection spots per square decemeter of leaf area while another goes as low as 7 infection spots per square decemeter. This same individuality is also very well shown in 'variety 17, Giant Pascal and No. 23, Prencn' s Success. The fact that each piant has an individuality, is of much importance to a breeder about to begin the task of breeding a disease resistant strain of celery. Instead of trying to se- lect any one particular variety, the breeder must start with the individual plant and first test its power of transmission of the immunity character and then by selection, v;here possible . 38. gradually breed up the immune type. The second point is that each variety has a different range of variability^. The French grown seed of variety Ho. 1 Golden Self Blanching, having the greatest range, while variety Ho. 23, French's Success has the least range. This last named variety is also the inost nearly immune. Since the seed used was not from a pure strain but merely commercial seed, the question naturally arises as to the genetic relationship between the various individuals in the different varieties. This, of course, depends upon the method of pollination. As to this Knuth in his Handbook of Flower Pollination, Vol, II. says, "1107, Apium graveolens L. , Kirchner states that the small whitish flowers of this species are self-fertilized, perhaps in consequence of imperfect pro- tandy. " The fact that celery flowers are self-fertilized make the predeeding points more significent, i.e. the individuality of the plants is due to the transmission of heritable characters from self fertilized parents and not the results of the breaking up of hybrid forms. The other point emphasized is that the variability of the different varieties indicates a mixed popula- tion much the same condition as breeders of cereals in Germany had bu mass selection before the method of selection was dis- covered and which is now used oy ITilsson of Sweden. The writer has not been able to find any other method used in breeding celery other than selection. It was simply a process of selecting pure strains, so that commercial var- 39. ieties include several strains within a given variety. CHARACTER OF THE SPOTS. The character of the infection spots varied with the particular variety. In an article on, "The Possible Source of d Origin of the Leaf-Spot disease of Cultivated Celery", a proof sheet of which was kindly sent to the writer hy the author, Dr. George H. Pethybridge of Dublin, Ireland, it is stated that this disease was found on wild celery growing in West G-alway, Ireland. Infection was obtained on cultivated celery from 66 spores taken from wild celery. The spores on wild celery leaves are described as "seldom, if ever, confluent; they were relatively small, and retained their form and individuality even on old leaves which were apparently otherwise dying a natural death." Hov/ever, when spores from these same small spots on wild celery were used to inoculate the cultivated celery "the attack was much more se- vere and in fact resembled in every v/ay the appearance of the now, unfortunately, too well known leaf spot disease on cul- tivated celery. The spots enlarged in area and confluent ,. pjcnidia appeared- in abundance, and the foliage undervifent de- a cay, apparently asAdirect result of the attack of the fungu^, « 8 To be published in the Jour. Hoy. Hort. Soc. vol. XL part 3, 1915. 68 Dr. Pethybridge kindly sent the writer specimens of wild celery that were infected with Septoria petroselini Desm. var. Apii Br. et Cav. and also specimens of cultivated celery that had been inoculated from spores taken from the wild celery plants. 40. The above observations of Dr. PethyToridge are of interest for the following reasons, - 1, In the present experiment the same thing v/as observed in the different varieties in connection with the character of the infection siJOts. In such varieties as Golden Self Blanching and Columbia the spots spread so that in some cases nearly the entire lea,f became one large spot of infection. In other var- ieties as i'rench' s Success and Celeriac there v;ere a large number of spots which were no larger than the point of an ordinary lead pencil. These spots did not spread but remained distinct even after the leaf had died, 2. It seems that this is one way that can be relied upon as indicating the immunity of a variety of celery. 41. BIELIQGRAPtlY. ATDercombie, Jojan 1786 The gardener's daily assistant in the modern practice of English gardening. Abercomhie, John 1805 Every man his own gardener, being a new s.nd much more complete gardener's calender. Bain, Samuel M. and Essary, Samuel H. 1907 Some results in selecting red clover for disease resistance. A. B. A. Rep. _3:. 359-360. Biffin, R. K. 1905 Mendel's laws of inherita,nce and wheat breeding. Jour, of Agr. oci. 1:40-44. Biffin, R. H. 1907 Studies in the inheritance of disease-resistance. Jour. Agr. Sei. 2:109-128. Biffin, R. H. 1911 Inheritance in disease-resistance. Jour. Agr. Sci. 4:421-429. Blackwell, ffraneis and Hensley, W. B. 1886 Compilation of plants in Eastern Asia. Jour. Linn. Soc. 23:328. Blinn, Philo K. 1905. A rust resisting cantaloup. Colo. Agr. Exp. Bui. 104:4-15 pi. X. Bois, D. and Cornu, Maxime 1893-1899 Dictionnaire D'Korticulture 43. immunity of Coffea congenesis to liemileia vastatrix) Jour. Agr. Prop. 8:363-364. Dussert, P. 1910 (Prench title) llotes on Coffee resistant to Hemileia vastatrix. Agr. Pays-Chauds 10_;337-33S Dybowski, J. 1909 (Prencii title) Tiie resistance of Coffea congensis to Hemeieia vastatrix. Agri. Prot. Pays-Chauds 9:159-160. Parrer, \V. 1898 The making and improvement of wheats for Australian conditions. The Agr. Sci. C-az, , iTev/ South \¥ales, 9:131-168; 241-260. Gerard, John 1597 The Herhali or general historie of plants, Hals ted, Byron D. 1897 Experiments with carrots. ¥, J. Agr. Exp. Sta.. Pvep. 18:325-326. Hansen, if. E, 1905 Mildew-resistant sand cherries'^and roses. A. B. a. Rep. 1:190-191. Henslow; George 1894 Our common vegeta^lales; their origin, history, and value as foods. Jour. Roy. Hort. Soc. 17 : 43-127. Henslow, George 1899 On the importance of light and heat to plants. Jour. Roy. Rott. soc. 23:23-77. 42. Bolley, H. L. 1901 Flax wilt and flax sick aoml. N. D. Agr. Exp. Sta. Bui. 50:27-58. Bolley, H. L. 1905 Breeding for resistance or immunity to disease. A. B. A. Rep. 1:131-135. Bolley, H. L. 1908a The constancy of mutants; the origin of disease resistance in plants. A. B. A. Rep. 4: 121-129. 190813 Breeding fiber flax for resistance to disease. A. B. A. Rep. 4:227-229. Bunzel, h. H. 1914 Oxidases in healthy and in curley-dvvarf potatoes. Jour. Agr. Res. 2:373-404. Butler, E. J. ,/ 190o The "bearing of Mendelism on the susceptibility of wheat to rust. Jour. Agr, Sci. 1:361-363. de Condolle, A lbti2 Origin of cultivated plants. Dodoeus, Remherte 1578 ITiev/e Kerba-ll (history of plants) London. Dorsett, P. H. 1900 Spot disease of the violet (Alternaria violae n, sp, ) U. S. D. A. Div. Veg. Phy. and Path. Bui. 23:1-16 pi. VII. Dubard, Marcel 1908 Sur I'iramunite du "Goffea congensis" var. Chaloti pierre a 1' "Hemileia vastatrix". (The 44. toward, Albert et al 1'907 Notes on immune wheats. Jour. Agr. Sci. 2:278-280. llusman, George G. 1910 Grape investii^ations in the Vinifera Regions of the United States with reference to resistant stocks, direct producers, and viniferas. U. S. D. A. Bur. PI. Ind. Bui. 172:9-74. PI. 1-8. Jackson, H. S, 1908 Development of disease resistance varieties of plants. Tran. Mass. Hort. Soc. 1908 :123-157. Johnson, Thomas 1633 The Herball or general historic of plants. Jones, L, R. 1905 Disease resistance of potatoes. U. S. D. A. But. PI. Ind. Bui. 87:1-39. Jones, L. S. , Giddings, N. J. , Lutman, B. -P. 1912 Invest ig9,tipns of the potato fungus Phytophthora infestans. Vt. Agr. Exp. Sta. Bui. 168 :9-100 PI. 3-10. Knuth, Paul and Ainsv/orth Davis, J. R. 1906-1908 Hand'bood of flower pollination, 3 vol. '-^he Clarenden Press, Oxford. Lewton-Brain, L. 1903 Disease-resistant varieties of plants. West Indian Bui. 4:48-57. Marryat, Dorthea G. E. 1907 Notes on the infection and histology of two wheats immune to the attacks of Puccinia Glumarum, yellow rust. Jour. Agr. Sci. 2:129-138. PI. 1. 45. Mawe, Thos. and ATaercombie, John 1797 The universal gardener and botanist, etc. Mawe, Thos 1829 The complete gardener being the gardener's calender. Meager, Leonora 1688 The English gardener. Miller, Philip 1752 The gardener's dictionary, 6th. ed. Miller, Philip 1765 The gardener's Kalender, 14th. ed. Miller, Philip 1768 The gardener's dictionary, 8th. ed. Miller, Philip a,nd Martyn, Thos. 1807 Gardener's and "botanist's Dictionary. 4 vols. Horton, J. B. 1913 Methods used in breeding asparagus for rust resist- ance. U, S. D. A. BUr. PI. Ind. Bui. 265 :9-60 PI. 1-18. Or ton, V/. A. and V/ebber, H. J. 1902a Some diseases of the cowpea. U. S. D. A. Bur. PI. Ind. Bul. 17:9-35. 1902b On the breeding of disease resistant varieties. Memoir IT. Y. Hort. Soc. 1:41-53. PI. 4. Or ton, W. A. 1905a Plant breeding as a factor in controlling plant diseases. A. B. A. Rep. ]^^;f^^B--'-2^^ / .' / 9 ' '^ Z 1905b Breeding disease resistant plants. A. B. A. Rep. 1:202-207. 46. Or ton, W. A. 1908 On the theory and practice of "breeding disease resistant plants. A. E. A. Rep. 4:144-156. V figs. Or ton, W. A. 1911 The development of disease resistant varieties of plants. Gonf. Intern, de. Geraet. 4:247-265, Parkinson, John 1640 Theatrum Botaniacum or theatre of plants. Phillips, Henry 1822 History of cultivated vegetables, 2 vols. London. Pole-Evans, I. B. 1911 South Africa,n cereal rusts, with observations on the problem of breeding rust-resistant wheats. Jour. Agr. Sci. 4:95-104. Bibl. Reed, George M, 1908 Infection experiments with Erysiphe Cichoracearum DC. Univ. Wise. Sci. Series Bui. 3:337-416. Reed, George IvI, 1912 Infection experiments with the powdery mildew. Phytopath. 2:81-87. Reid, Clement 1907 On the preglacial glora of Britain. Jour. Linn. Soc. 38:206-226. 2 PI., 64 figs. Salmon , E. S-. 1906 On raising strains of plants resistant to fungous diseases. Internat. Gonf. onGBnetics. 3_:378- 384. 47. Sharrock, Robert 1660 The history of the propogation and improvement of ' vegetaliles by the concurrence of art and nature. Spinks.G. T. 1912 Factory affecting susceptibility to disease in plants. Jour. Agri. Sci. _5:231-247. Stakman, Elvin Charles 1913 A study in cereal rusts. Thesis (Ph. D. ) Univ. Y/isc. Taylor , G. M. 1911 Disease resisting potatoes. Gard. Chron. 49:181. V/ard, Marshall H. 1902 On the question of "predisposition" and ^immunity" in plants. Proc. Cambridge Phil. Soc. 11:507- 328. Wright, C. H. 1909 Flora of Falkland Island, Jour. Linn Soc. 59:520. Zimmerman, A. 1897 Met Groepsgewijs afterven der Koffie heesters in gestoten piantsvenen Tej'-smannia. Key to t he Varietlea Of Celery No. 1 Golden Self Blanching No. !? Golden Self Blanching llo. 10 Maule's American Yellow Ho. 11 \7hite Pliime No, 17 Giant Pascal No. 20 Columbia No. 23 Frenchs' Success No. 24 V/inter w^ueen No. 29 New Rose No. 30 Kalamazoo No. 31 Celeriac- Turnip Rooted, No. 38 Boston Market No. 43 Giant Holden Heart ITame of Company from V/nom Seed waa Obtained A. W. Gilman. Burpee (American Seed) W. H. Maule, Phil. Burpee. D. M. Ferry and Go. ti ti II II II It n II Burpee J. M. Thorburn and Co. II II Burpee C. C. Morse and Co. II It Table I. Series A. Plant No. of Leaf Area Total iJo. Spots No. Spots No. Leaves of 10 Leaf per per Leaves Area- Plant sq, deem. sq. cm. 1-1 46 350 1610.00 437 27.12 1-2 43 180 1849.00 369 20.00 1-3 47 107 502. 90 226 44.95 7-1- 51- 151 770.10 340 44.20 7-2 46 197 906.20 213 23.50 7-3 40 75 300.00 208 69.32 10-1 27 128 345.60 69 . 19.97 10-2 37 84 310.80 120 38.55 lffi-3 4©; 109 ' 436. 00 97 22. 26 11-1 49 103 504. 70 89 17.65 11-2. 60 91 546. 00 193 35.38 11-3 68 139 945. 20 175 18.52 17-1 89 121,9 1084. 91 406 37.40 17-2 93 153 1422. 90 449 31.50 17-3 56 117 655.20 466 71.05 20-1 42 137 575.40 172. 29.86 20-2: 32 228 729. 60 490 66.28 20-3 40 212 848.00 533 62.90 23^-1 67 68 455.60 164 35.98 23-2 44 132 580. 80 178 30.68 23-3 46 88 404. 80 169 41.78 24-1 63 158 995.40 266 26.73 24-2 66 174.6 1152.36 ■ 133 11.55 24-3 55 155 852.50 128 14.16 29-1 49 130 637.00 638 100.20 29-2 61 142 862.20 406 47.15 29-3 56 188 1052. 80 458 43.42 30-1 53 128 678.40 485 71.55 50-2 59 134 790.60 500 63. 25 30-3 55 145 797.50 708 88.82 31rl 63 140 882. 00 109 12. 37 31-2 59 94. 554.60 55 99.25 31-3 61 170 1037.00 156 15.05 38-1 95 97 921. 50 684 74.30 38 -2c, 50 147 735.00 806 10. 98 38-3 62 152 942. 40 271 28.78 43-1 63 213 1341. 90 771 57.47 43-2 60 123 738. 00 115 15.58 43-3 60 115 690.00 365 52.89 Table II. Series B. Plant No. of Leaf Area Total L No. Spots No. Spots No. lieaves of 10 Lieaf per per Leaves Area^. Plant sq. deem. sq. cm. 1-1 58. 190 1102. 1010 91.56 1-2 40 187 748.0 385 51. 5Q 1-3 52 121 629.0 750 119. 15 1-4 49 114 598.6 490 87.71 7-1 62 .132 818.4 200 24^ 47 7-2 60 145 870.0 1012 116. 55 7-3 43 193 829.9 326 39.31 7-4 43 172 739.6 168 22.73 7-5 50 147 736. 163 22.18 10-1 32 111 355.2 37 10.42 10-2 46 118 542.8 191 35,16 10-3 51 88 448.8 141 31,41 10-4 48 134 643. 2 228 35.49 10-5 47 160 752.0 115 15. 29 11-1 60 140 840. 75 8.93 11-2 60 114 684.0 74 10.82 11-3 46 145 667.0 320 47.98 11-4- 4a 132. 528.0 25a 47.30 17-1 39 119 464. L 625 13.47 17-2 44 154 677.6 360 53.24 17-3 37 136 503.2 225 44*75 17,r4 53 112 593.6 78a 13.15 20-1 41 165 676.5 441 65.25 20-2 36 215 774.0 225 3 9. .10 20-3 36 147 529.2 375 70.80 2a-4 35 212 742,0 520 70. .20 23-1 47 148 695.6 160 23.00 23-2 53 124 657.2 140 20.88 23-3 59 175 1032. 5 130 12.59 23-4 46 118 566.4 95 16.80 24-1 63 229 1442. 7 324 22.47 24-2 46 179 823.4 170 20.65 24-3 59 172 1014. 8 509 50.22 24-4 79 131l 1034. 9 470 45,40 29-1 40 142 648.0 466 71. 91 29-2 60 177 1062.0 870 81.92 29-3 65 213 1384. 5 923 66.66 29-4 53 136 720,8 400 55.49 TalDle II. Series B. Cont. Plant No. of Leaf Area Total No. Spots No. Spots Ho. Leaves of 10 Leaf per per Leaves Area Plant sq. deem. sq. dm. 30-1 48 134 643. .2 450 70.00 30-2 57 133 758.1 530 69. 98 30-3 64 118 755.2 119 15.75 30-4 49 168 823.2 421 51.18 31-1 59 67 395.3 140 35.45 31-2 65 103 669.5 250 37.38 31-3 60 124 744.0 167 22.45 31-4 64 ■69 441,6 130 29.52 38-1 51 204 1040. 4 230 22.11 38-2 52 173 899.6 370 41.20 38-3 52 219 1138. 8 500 43.90 38-4 40 202 808.0 460 56. 90 43-1 4.9 155 759.5 197 25. 94 43-2 60 108 648.0 446 68.80 43-3 57 154 877.8 184 20. 98 43-4 62 112 694.4 470 67.73 TaTole III. Series C. Plant No. 'of Leaf Area Total No. Spots No. Spots No. Leaves of 10 Leaf per per Leaves Area Plant sq. deciju sq. cm. 1-1 51 238 1213. 8 297 24,45 1-2 41 223 914. 3 448 49.15 1-3 45 189 850,5 157 18.47 1-4 50 209 1045.0 127 12.15 1-5 35 195 682.5 53 7.77 Il-l 74 134 991. 6 64 6.47 11-2 67 84 571.2 66 11.57 11-3 75 103 751.9 79 10.51 11-4 45 198 891.0 132 14, 84 11-5 80 165 1320. 221 16. 75 17-1 57 149 849.3 299 35,20 17-2 51 178 907.8 257 28.15 17-3 49 159 779.1 119 65.50 17-4 30 111 533.0 104 31.22 17-5 58 126 730.8 165 22.60 20-1 47 226 1062. 2 124 11.70 20-2 35 296 1036. 230 22,22 20-3 59 192 1132. 8 346 30.50 20-4 47 225 1057.5 219 20. 72 20-5 57 180 1026. 167 16.29 23-1 52 151 785.2 20 2.55 23-2 72 92 662.4 41 6.18 23-3 65 106 689.0 85 12.34 23-4 82 101 828.2 68 8.22 23-5 50 81 405.0 47 11.61 24-1 43 209 898.7 192 21.35 24-2 71 122 866.2 241. 27.84 24-3 58 142 823,6 119 14.45 24-4 50 167 835.0 360 43,20 24-5 54 170 918.0 202 22.00 29-1 45 118 531.0 117 22.08 29-2 53 167 832.1 57 68.50 29-3 60 156 936.0 281 30.25 29-4 50 134- 670.0 52 77.65 29-5 46 145 667.0 56 84.00 Table III. Series 0.: Cont. Plant No. of Leaf Area Total No. Spots No. Spots No. Leaves of 10 Leaf per per Leaves Area Plant sq. deem. sq. cm. - ■ s 30-1 54 163 880.2 98 11. IS 30-2 76 149 1132. 4 195 17.23 30-3 56 141 789,6 75 94,99 30-4 49 177 867.3 92 106. 00 30-5 42 219 919.8 90 97.85 31-1 54 149 804.6 178 22. 14- 31L-2 75 124 930,0 229 24.65 31-3 80 95 760.0 284 37, 39 31.4 54 117 631.8 51 8,08 31.5 80 115 920.0 88 9.57 38-1 '30 207 621.0 120 19.31 38-2 60 149 894.0 228 25.51 38-5 61 153 933. .3 233 29.80 38-4 57 156 889.2. 430 48.37 38-5 55 159 874.5 132 15. 12. 43-1 35 243 850.5 307 36.09 43-2 52 141l 733.2, 261 35.60 43-3 49 161 788. 9 236 29.80 43-4 65 132 858.0 315 36.71 43-5 65 105 682.5 187 27. 40 Table IV. Series Di Plant No. of Leaf Area Total No. Spots No. Spots No. Eeaves of 10 Leaf per per Leaves sq. , Area Plant sq, deem. cm. 1-1 63 171.16 907. 15 199 21. 90 1-2 50 149, 00 745. 00 345 46.30 1-3 49 184. 00 901. 60 73' 8.11 1-4 58 136. 50 791. 70 137 I7w 31 11-1 91 42.50 386.75 83;. 22.48 11-2 65 126. 00 819. 00 106 12. 95 11-3 81 126. 00 1020. 60 56 54.80 11-4 77 153.00 1178.00 129 10. 99 17-1 37 149. 50 553. 15 480 86.75 15-2 53 120. 00 636.00 661 103, 80 17-3 60 132. 00 792. 00 539 68.15 17-4 55 100. 50 552. 75 296 " 53. 65 20-1 59 195.00 1150. 50 386 33.50 20-2 47 160. 00 782, 00 202 26.87 20-3 70 90.50 633. 50 316 49.85 20-4 60 166.00 996.00 362 36.38 23-1 59 142. 00 837.80 74 8.83 23-2- 70 118. 00 826. 00 112, 13.56 23-3" 65 96.00 624. 00 118 18.90 23-4 69 82.00 565.80 206 36. 41 24-1 58 131. 00 759.80 105 13.85 24-2 59 154, 00 908. 60 71 7.82 24-3 52 138,00 717.60 52 7.25 24-4 53 171. 00 906.30 124 13.68 29-1 49 160.00 784. 00 109 13.90 29-2 51 102, 00 520. 200 33 6.33 2.9-3 48 129. 00 619. 20 80 12. 92 29-4 41 164, 00 672.40 87 12.95 30-1 51 174.00 887.40 133 14.99 30-2 62. 140, 00 868. 00 342-, 39.35 30-3 33 153; 00 504. 90 107 21.20 30-4 57 Mi, 00 826. 50 24a. 29.30 31-1 82 7 7 3. .48 602. 54 61 10.13 31«.2 62 45.00 279*00 48 17.20 31-3 67 93.00 623. 10 119 19. 10 31-4 47 103.00 484. 10 29 5. 98 Table IV. Series D, Gont. Plant No. of Leaf Area Total No. Spots No. Spots No. Leaves of 10 Leaf per per Lieaves: Area. Plant sq, deem. sq, cm 38-1 76 99.00 752, 40. 449 59.75 38-2 56 107. 00 599.20 305 50.85 38-3 64 108, 00 691.20 105 15.20 38-4 74: 109. 00 806. 60 606 75,20 43-1 64 I25w 00 800. 00 251 31.38 43-2 50 144. 00 720. 00 194 26. 95 43-3 65 148, 00 962. 00 224 23.28 43-4 73 92.00 671.60 205 30. 52 /K/uJ^hffr a/ -^/'^^■^ Z^'' ^J-^e^^. Ni/mh^r ^/ ^/'^T^J /"^"^ Sf.j7^^:^ ^ ^ Ci ^ Ncfrr^i^^r ^/^/'^T^-^/'-'^-^/-^^^'^- Numi>ey' o/ ■^/^^^■^ /'^^ -^^ ^^^^- u /0 ^0 30 ^a ^a d,^f /a S"^ ^^ /^^ //^^ /^l//77^er- o/^ ^/'^Zi /'^^ ^y. /7&c/??^ \ bi V>i ^ TV s; ^^ 5^ fs/t/mb e/^ o/ -^/'^/t^ /^er_5j>.J7ec/77. l.>J ■"'A) S^ <^, ^'f I Numi^r ^y- s^o^zs /'^^ -tf- ^^ C/7? _ ta ^ VJSn ^'^1 A/c/mter o/ 3 pots /^e/- -sy. /p^c^. -^' Num/^^r of 3^af-j> /?er 3f. c/e^/v. A/un7^er oy 3^ot^ Ad'^ 3y, c/ec^. «^ C^ MJ N>^ (Js \j ^ "SN A/i/zT^^^/- oy 3^07^^ Aer S^. c/je^/?7. A/,/noh/?r of ^Sydof^ Aifz-c^. ^r/7?. Plate XV. Late Blight of Celery on Mo. 1 Golden Self -Blanching variety ITo. 17 Giant Pascal variety. Plate XVI. Late Blight of Celery on No, 30 Kalamazoo variety No. 7 Golden Self-Blanching variety. (Burpee) Plate XVII. Late Blight of Celery on Ho. 10 Maule's America,n Yellow variety. No. 11 White Plume variety. Plate XVIII. Late Blight of Celery on ITo. 20 00101111313, variety. No. 38 Boston Market variety. Plate XIX. Late Blit:;ht of Celery on No. 23 ITench's Success variety. No. 24 Winter Q,ueen variety. Plate XX. Late Blight of Celery on No. 29 Hew Rose variety. ITo. 43 Giant Golden Heart variety. Plate XXI. Late Blight of Celery on Uo. 31 Celeriac- Turnip Rooted variety (two plants)