The Effect Of Time Of Nitrate Application Upon The Growth Of Barley Cultivars Of Differing Endogenous Nitrogen Levels: Longer Termexperiments

Abstract

The effect of time of nitrate application was examined in cultivars with either a high or low endogenous nitrogen content in the grain. In low-nitrogen cultivars delay in the application of nitrate beyond day two from planting leads to considerable reductions in total dry matter, particularly of the shoot. Maximum leaf length of all the main-stem leaves was reduced and their date of emergence retarded by several days. There was no effect upon the final length of tiller leaves, though tiller emergence was appreciably retarded. These effects were absent or less marked in cultivars with a high endogenous nitrogen content or where low-nitrogen cultivars were supplied with nitrate during germination. The results in total indicate that inadequate nitrogen supply to the seedling axis produces irreversible detrimental effects upon plant growth which may ultimately reduce yeild. © 1979, Annals of Botany Company.43675376