Effects of Fertilizers on Slow Rusting in Wheat

Abstract

In an NPK factorial experiment, ''Marquis'' wheat rusted rapidly with Puccinia graminis f. sp. tritici (wheat stem rust pathogen) and P. recondita f.sp. tritici (wheat leaf rust pathogen), ''Lee'' rusted moderately rapidly with both pathogens, and ''Thatcher'' rusted slowly with the stem rust pathogen and rapidly with the leaf rust pathogen. The interation of cultivars with fertilizer treatments was not significant. NH4NO3 enhanced leaf rust development in 1975, and stem rust development in 1979, but did not affect rust development in other years as indicated by area under the disease progress curve. P2O5 enhanced stem rust development in 1977, but did not affect stem rust or leaf rust development in any of the other 5 yr of the study. K2O enhanced leaf rust development in 1973 and stem rust development in 1979, but did not affect either rust in other years.