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Soilborne wheat mosaic virus (SBWMV) is a member of the genus Furovirus of plant viruses. SBWMV is transmitted to wheat roots by the plasmodiophorid vector Polymyxa graminis. Experiments were conducted to determine the path for SBWMV transport from roots to leaves. The results of immunogold labeling suggest that SBWMV enters and moves long distance through the xylem. SBWMV may enter primary xylem elements before cell death occurs and then move upward in the plant after the xylem has matured into hollow vessels. There is also evidence for lateral movement between adjacent xylem vessels.

A study was conducted to determine the inheritance of resistance to races 44 and 52 of leaf rust (causal organism Uromyces appendiculatus (Pers. ex Pers.) linger var. appendiculatus) in the dry edible bean (Phaseolus vulgaris L.) cultivars ‘T‐39,’ ‘Aurora,’ and ‘Olathe.’ T‐39 and Aurora each express hypersensitive resistance to race 52 but are susceptible to race 44. Olathe is hypersensitive resistant to race 44 and susceptible to race 52. Crosses were made between these cultivars and with ‘UI‐114,’ a pinto bean cultivar susceptible to both races. Resistance of Ft progeny and segregation ratios within F2 populations and among F3 progeny from individual F2 plants of crosses with UI‐114 indicated that resistance to each race was controlled by a single, dominant gene. Segregation ratios of the F2 population and F5 progeny from individual Fj plants of the cross Olathe ✕ T‐39, inoculated with race 44 only, indicated that complementary dominant genes controlled resistance to race 44. Segregation ratios of genes for resistance to races 44 and 52 in progenies of Olathe ✕ Aurora indicated independent assortment without epistasis. The following tentative genotypes for rust reaction of the cultivars studied are proposed: Olathe ‐ UraUraUrcUrcthe cultivars studied are proposed: Olathe ‐ UraUraUrcUrcthe cultivars studied are proposed: Olathe ‐ UraUraUrcUrcurburb; T‐39 ‐ urauraurcurcUrbUrb; Aurora ‐ urauraUrcUrcUrbUrb; UI‐114 ‐ urauraUrcUrcurburb.