1184 



MANUAL OF DETERMINATIVE BACTERIOLOGY 



Other properties : Active after storage 

 27 days at -6° C. 



Literature: Brandes, Jour. Agr. Res., 

 19, 1920, 131-138, 517-522; U, 1923, 247- 

 262; Desai, Current Science, 3, 1935, 18; 

 Forbes and Mills, Phytopath., 33, 1943, 

 713-718; Ingram and Summers, Jour. 

 Agr. Res., 5£, 1936, 879-888; Kunkel, 

 Bull. Exp. Sta. Hawaiian Sugar Planters' 

 Assoc, Bot. Ser., 3, 1924, 115-167; Matz, 

 Jour. Agr. Res., 46, 1933, 821-839; Raf ay, 

 Indian Jour. Agr. Science 5, 1935, 663- 

 670; Sein, Jour. Dept. Agr. Porto Rico, 

 U, 1930, 49-68; Stoneberg, U. S. Dept. 

 Agr., Tech. Bull. 10, 1927; Tate and 

 Vandenberg, Jour. Agr. Res., 59, 1939, 

 73-79. 



26. Marmor cepae H. {loc. cit., 66). 

 From Latin cepa, onion. 



Common name: Onion yellow-dwarf 

 virus. 



Host: LILIACEAE — Allium cepa L., 

 onion (the variety viviparum Metz. is 

 symptomless when infected and may 

 serve as an unrecognized reservoir of 

 virus). 



Geographical distribution : United 

 States, Germany, Czecho-Slovakia, Rus- 

 sia, New Zealand. 



Induced disease : In onion (most varie- 

 ties), yellow streaks at base of developing 

 leaf, followed by yellowing, crinkling, 

 and flattening of newly formed leaves; 

 leaves prostrate, flower stalks bent, 

 twisted, stunted; plants reduced in size, 

 bulbs small, yield of seeds reduced. A 

 few varieties of onion are relative!}' 

 tolerant, and the tree-onion, var. vivi- 

 parum is symptomless after infection. 



Transmission: By inoculation of ex- 

 pressed juice. By 48 of 51 tested species 

 of aphid, principally Aphis rum ids Linn., 

 A. maidis Fitch, and lihopalosiphiim 

 prunifoliae Fitch (APHIDIDAE). Not 

 through seeds from diseased plants. Not 

 by contaminated soil. 



Thermal inactivation : At 75 to 80° C 

 in 10 minutes. 



Other properties : Virus withstands di- 

 lution to 10~^ storage at 29° C for about 



100 hours and storage at — 14° C for more 

 than time tested (6 hours), but is inacti- 

 vated by drying in leaf tissues. 



Literature : Andreyeff, Rev. Appl. 

 Mycol., 17, 1938, 575-576; Blattny, Och- 

 rana Rostlin, 10, 1930, 130-138; Bremer, 

 Phytopath. Ztschr., 10, 1937, 79-105; 

 Brierley and Smith, Phytopath., 34, 1944, 

 506-507; Chamberlain and Baylis, New 

 Zealand Jour. Science and Technology, 

 21, 1939, 229A-236A; Drake et al., Iowa 

 State Coll. Jour. Science, 6, 1932, 347- 

 355; Jour. Econ. Ent., 26, 1933, 841-846; 

 Henderson, Phytopath., 20, 1930, 115 

 (Abst.); Iowa State Coll., Research 

 Bull. iSS, 1935, 211-255; Melhus et al., 

 Phytopath., 19, 1929, 73-77; Porter, U. 

 S. Dept. Agr., Plant Dis. Rept., 12, 1928, 

 93; Tate, Iowa State Coll. Jour. Science, 

 14, 1940, 267-294. 



27. Manner scillearum Smith and 

 Brierley (Phytopath., 34, 1944, 503.) 

 From New Latin Scilleae, name of tribe 

 in which hosts are classed. 



Common name : Ornithogalum-mosaic 

 virus. 



Hosts: LILIACEAE (of the tribe 

 Scilleae) — Ornithogalum thyrsoides Jacq. ; 

 probably also Galionia candicans Decne . ; 

 Hyacinthus orienialis L., hyacinth; La- 

 chenalia sp. 



Insusceptible species : LILIACEAE 

 (of the tribe Scilleae) — Muscari botry- 

 oidcs Mill. ; Scilla peruviana L. ; Camassia 

 leichtlinii (Baker) S. Wats.; Hyacinthus 

 azureus (Fenzl.) Baker. AMARYLLI- 

 DACEAE — Pancratium maritimum; Ze- 

 phyranthus sp. IRIDACEAE—Tri- 

 toniacrocata (L.) Ker. LILIACEAE — 

 Agapanthus africanus; Allium cepa, 

 onion; A. cernuum Roth.; A. fistulosum 

 Ij.; A. porrum L. ; Gloriosa rothschildiana 

 O'Brien; Lilium formosanum Stapf.; and 

 L. longiflorum. SOLAN ACE AE—Ni- 

 cotiana tahacum L. 



Geographical distribution : United 

 States (Oregon; probably also Alabama 

 and presumed to be widespread in plants 

 of the squill tribe, Scilleae, of the family 

 LILIACEAE). 



