1174 



MANUAL OF DETERMINATIVE BACTERIOLOGY 



8, 1918, 32-33; Kendrick, Phytopath., 24, 



1934, 820-823; Mahoney, Proc. Am. Soc. 

 Hort. Sci., 332, 1935, 477-480; Price, 

 Phytopath., 25, 1935, 776-789; 29, 1939, 

 903-905; Am. Jour. Bot., 27, 1940, 530- 

 541; Storey, Ann. Appl. Biol., 26, 1939, 

 298-308. 



Strains : Various host plants seem to 

 have induced specialization of cucumber- 

 mosaic virus in strains particularly 

 adapted to existence in their tissues. 

 Several of these and certain laboratory- 

 derived strains useful in technical proce- 

 dures have been distinguished from the 

 type, var. imlgare H. {loc. cit., 31), by 

 varietal names, as follows : 



9a. Marnior cucumeris var. commelinac 

 H. {loc. cit., 35). From New Latin 

 Commelina, generic name of weed serving 

 as a natural reservoir of this strain. 

 Common name : Southern celery -mosaic 

 strain of cucumber-mosaic virus. Differ- 

 ing from the type in severity of disease 

 induced in celery and some other plants. 

 Transmitted by Aphis gossypii Glov., A . 

 maidis Fitch, and Pentalonia nigro- 

 nervosa Coq. (APH IDIDAE) . (Price, 

 Phytopath., 25, 1935, 947-954; Wellman, 

 ibid., 24, 1934, 695-725, 10.32-10.37; 25, 



1935, 289-308, 377-404.) 



9b. Marmor cucumeris var. phascoli 

 H. (loc. cit., 36). From New Latin Pha- 

 seolus, generic designation of lima bean. 

 Common name: Lima-bean strain of cu- 

 cumber-mosaic virus. Differing from 

 type of species in ability to cause a chlo- 

 rotic mottling disease in lima bean in 

 nature. (Harter, Phytopath., 26, 1936, 

 94; Jour. Agr. Res., 56, 1938, 895-906; 

 McClintock, Phytopath., 7, 1917, 60.) 



9c. Marmo7- cucumeris var . lilii YL. {loc. 

 cit. ,37). From Latin /(7i'H?«, lily. Com- 

 mon name : Lily-mosaic strain of cucum- 

 ber-mosaic virus. Differing from the 

 type variety by ability to persist in na- 

 ture in lilies, producing masked infection 

 or chlorotic mottling unless in mixture 

 with lily-symptomless virus {Adelonosus 

 lilii), when a more severe disease involv- 



ing necrosis is induced. (Brierley, Phy- 

 topath., 29, 1939, 3; 30, 1940, 250-257; 

 Brierley and Doolittle, ibid., 30, 1940, 

 171-174; Ogilvie and Guterman, ibid., 19, 

 1929, 311-315; Price, ibid., 27, 1937, 

 561-569.) 



9d. Marmor cucumeris var. judicis H. 

 {loc. cit., 38). From Latin jwdex, judge. 

 Common name : Indicator strain of cu- 

 cumber-mosaic virus. Differing from 

 the type variety in inducing the forma- 

 tion of necrotic local lesions in zinnia 

 {Zinnia elegans Jacq., COMPOSITAE). 

 Previous infection of zinnia by other 

 strains of cucumber-mosaic virus in- 

 hibits the formation of these necrotic 

 local lesions, identifying the strains as 

 related to each other and to the indicator 

 strain. (Price, Phytopath., 24, 1934, 

 743-761 ; 25, 1935, 776-789.) 



9e. Marmor cucumeris var. vignae H. 

 {loc. cit., 39). From New Latin Vigna, 

 generic name of cowpea. Common name : 

 Cowpea-mottling strain of cucumber- 

 mosaic virus. Differing from the type 

 variety in producing systemic chlorotic 

 mottling, rather than reddish-brown ne- 

 crotic local lesions, in Black cowpea. 

 Not known in nature but derived experi- 

 mentally from a mild-mottling strain of 

 cucumber-mosaic virus during serial 

 passage in cowpea. (Price, Phytopath., 

 24, 1934, 743-761 ; 25, 1935, 776-789.) 



10. Marmor solani H. {loc. cit., 47). 

 From New Latin Solanum, generic name 

 of potato. 



Common names : Potato mild-mosaic 

 virus, potato virus A. 



Hosts: SOLAN AC EAE— Solanum. tu- 

 berosum. L., potato. Experimentally, 

 also Nicotiana tabacum L., tobacco; Sol- 

 anum nigrum L. var. nodiflorum; and 

 Datura stramonium L., Jimson weed. 



Geographical distribution : United 

 States, England, Holland. 



Induced disease : In potato, very mild 

 chlorotic mottling or masked symptoms 

 in some varieties (as Irish Chieftain), 

 systemic necrosis in others (for example," 



