FAMILY CHLOROGEXACEAE 



1161 



S6, 1936, 887-895; Takata, Jour. Japan 

 Agr. Soc, 171, 1895, 1-4; 172, 1896, 13-32 

 (Takata's papers, in Japanese, constitute 

 the first published record of transmission 

 by an insect of a virus causing disease in 

 a plant, the leaf hopper Deltocephaliis dor- 

 salis Motsch. transmitting dwarf -disease 

 virus to rice; see Fukushi, 1937, cited 

 above ) . 



3. Fractilinea tritici^IcKinney. (Jour. 

 Washington Acad Sci., 34, 1944, 327.) 

 From Latin triticum, wheat. 



Common name : Winter-wheat mosaic 

 virus. 



Hosts: GRAM IN EAE— Triticum aes- 

 tivum L., wheat; Secale cereale L., rye; 

 Avena byzaniina; A. fatua L., wild oat; 

 A. saliva L., oat; Hordeum vulgare L., 

 barley. 



Geographical distribution: Union of 

 Soviet Socialist Republics. 



Induced disease : In winter wheat and 

 rye, chlorotic mottling; profuse branch- 

 ing. In winter wheat, phloem necrosis; 

 chloroplasts few, small; vacuolate inclu- 

 sions in cells; nuclei enlarged and with 

 extra nucleoli ; no protein crystals of the 

 pupation-disease type in affected cells. 

 In spring wheat, barley, and oats, chlo- 

 rotic mottling without profuse branching ; 

 no proliferation of flowers, but grain is 

 rarely formed, most infected plants dying 

 before this stage of growth. 



Transmission : By leafhopper, Delto- 

 cephalus striatus L. (CICADELLIDAE), 

 with incubation period of 15 to 18 days. 

 Not by inoculation of expressed juice. 

 Not through soil. 



Literature : Zazhurilo and Sitnikova, 

 Compt. rend. Acad. Sci. U. R. S. S., ^5, 

 1939, 798-801 ; 26, 1940, 474-478; 29, 1940, 

 429-432; Proc. Lenin Acad. Agr. Sci., U. 

 R. S. S., 6, 1941, 27-29. [Rev. Appl. Myc, 

 19, 1940, 268; 20, 1941, 157, 396; 22, 1943, 

 59]. 



4. Fractilinea quarta (Holmes) cotrib. 

 nov. (Marmor quartian Holmes, loc. cii., 

 65.) From Latin quarius, fourth. 



Common name : Sugar-cane chlorotic- 

 streak virus or fourth -disease virus. 



Host : GRAMINEAE—Saccharum offi- 

 cinarum L., sugar cane. 



Geographical distribution : Java, 

 Queensland, Hawaii, Puerto Rico, Colom- 

 bia, United States (Louisiana). 



Induced disease : In sugar cane, reduc- 

 tion of growth rate; wilting at midday; 

 long, narrow, longitudinal streaks, of 

 creamy or white color, in the leaves. 

 Streaks 1/16 to 3/16 inches wide, gen- 

 erally less than 1 foot long, fragmenting. 



Transmission : Bj^ leafhopper, Draecu- 

 lacephala poriola Bsdl (CICADELLI- 

 DAE). Not demonstrated by inocula- 

 tion of expressed juice. 



Thermal inactivation: In cuttings, at 

 52° C in less than 20 minutes. 



Literature: Abbott, Phytopath., 28, 

 1938, 855-857; Sugar Bull., 16, 1938, 3-4; 

 Abbott and Ingram, Phytopath., 3^, 1942, 

 99-100; Bell, Queensland Agr. Jour., 40, 

 1933, 460-464 ; Martin, Hawaiian Planters' 

 Rec, 34, 1930, 375-378; Hawaiian Sugar 

 Planters' Assoc. Proc, 53, 1934, 24-35. 



5. Fractilinea zeae (Holmes) comb, 

 nov. {Marmor zeae Holmes, loc. cit., 59.) 

 From New Latin Zea, generic name for 

 corn (maize), from Latin zea, a kind of 

 grain. 



Common name: Maize-stripe virus. 



Host: GRAMINEAE~Zea mays L., 

 corn (maize). 



Insusceptible species: GRAMINEAE 

 — Saccharum officinarum L., sugar cane. 



Geographical distribution: Hawaii, 

 Tanganyika, Mauritius, Trinidad, Cuba. 

 Not in United States. 



Induced disease: In corn (maize), at 

 first few, elongated, chlorotic lesions near 

 base of young leaf, later enlarging and fus- 

 ing to form continuous stripes. Subse- 

 quently formed leaves banded and striped 

 variously. Vacuolate intracellular in- 

 clusions in cells of affected areas. 



Transmission : By leafhopper, Pere- 

 grinus maidis (Ashm.) (F ULGORI- 

 DAE) ; the incubation period in this in- 



