EFFECT OF PHYTOHORMONE DUSTS ON GROWTH AND YIELD OF WINTER WHEAT VARIETIES

Abstract
Various concentrations of indolyl- and naphthylacetic acids were applied to ten varieties of winter wheat prior to planting in a replicated field trial, one-half of each plot receiving seed dusted with Ceresan plus phytohormone, and the other half receiving an equal quantity of seed of the same variety dusted with Ceresan only.Some differences between the hormone-treated and untreated sub-plots in respect of early growth and subsequent density of stand were apparent to visual inspection. There were also statistically significant differences in respect of straw production, and of yield, weight per bushel, and nitrogen content of grain. The effects on grain yield were complicated by the differential response of varieties to the same treatment, and at the higher concentrations some depressions of yield resulted. On the average both chemicals tended slightly to reduce the nitrogen content of the grain produced.The results as a whole seem to demonstrate the physiological activity of both substances tested when applied in this way. Further investigation of dosages, varietal characteristics, and seasonal effects, however, will be required before general conclusions can be reached.