Abstract
The present paper deals with the susceptibility of several species of Triticum, Aegilops and Agropyron, and certain hybrids between them, to wheat yellow-mosaic virus (Marmor tritici var. fulvum Mck.) when these plants were grown on virus-infested soil in boxes, with special reference to the relation between the susceptibility and genome constitution of the plants. The experimental results shown in Taales 1 and 2 may be summarized as follows:
(1) Regarding the genus Triticum, no plants belonging to ‘Einkorn’ (genome constitution: AA) and ‘Timopheevi’ (AAGG) were infected with the virus, but some of the tested plants belonging to ‘Emmer’ (AABB) and ‘Dinkel’ (AABBDD) showed the ordinary mosaic mottling with different infection rates.
(2) Three plants of Aegilops, Ae, caudata var. polyathera No. 1 (genomes: CC), Ae. squarrosa var. typica No. 1 (DD) and Ae. crassa No. 2 (DDMcr Mcr), were found susceptible.
(3) Among the tested plants of Agropyron, Ag. triticeum No. 1 and Ag. ciliare No. 2 showed only faint mottling on the young leaves, in which no intracellular inclusions (X-bodies) were recognized.
(4) In the test of hybrids, the plants of T. vulgare×Ag. elongatum (genomes: AABBDD) and Ae. sharonensis×T. durum (Ss1Ss1 AABB) were found to be susceptible to the virus, particulary the latter expressed severe mottling with the infection rate of 100 percent. On the other hand, however, the plants of Ae. sharonesis×T. aegilopoides (Ss1Ss11 AA) were immune.
(5) From these results, it seems that the genome ‘A’ in the plants tested bears no relation to the susceptibility of plants to the virus but that genomes ‘B’, ‘C’ and ‘D’ have some connection with the susceptibility. It appears, moreover, that the genome‘B’ is more dominant than the other genomes mentioned above.
