Fig. 1

Sensitivity of soybean accessions to TRSV infection. a Decision tree for determining TRSV sensitivities one to five. b Red arrows indicate necrotic reactions on different trifoliates. When the first trifoliate became necrotic, plants were rated with a sensitivity of five. c Necrosis of the second trifoliate at the bud stage typifies sensitivity four. d Plants that had necrotic spots on first trifoliate leaves belonged to sensitivity three. e Plants in sensitivity two displayed clear mosaic symptoms on the first trifoliate. f Plants in sensitivity one were stunted with chlorosis. g The distribution of TRSV sensitivity on 697 soybean accessions