Effect of Low Temperature on the Latent Period of Slow and Fast Rusting Winter Wheat Genotypes. Dennis A. Johnson, Assistant Professor, Texas A&M University Agricultural Research Station, Vernon 76384. Plant Dis. 64:1006-1008. Copyright 1980 American Phytopathological Society. DOI: 10.1094/PD-64-1006.

The latent period of fast and slow rusting winter wheat lines infected with Puccinia recondita f. sp. tritici was studied at 27, 21, 16, 10 and 4 C in growth chambers and in the field during late winter in Texas. In growth chambers, the latent period lengthened as the temperature decreased, but the latent period of the slow rusting lines increased more than that of the fast rusting lines. In the field, the latent period of the slow rusting lines was significantly longer than that of the fast rusting cultivars. The longer latent period of slow rusting winter wheat cultivars may be effective in reducing the rate of leaf rust development during the winter in Texas.