The Effect of Auxins on Seed Yield Parameters in Wheat, Pea and Canola Grown Under Controlled Environment and Western Canadian Field Conditions

Abstract

Experiments in this thesis test the hypothesis that foliar application of the auxins 4-chloroindole-3-acetic acid (4-Cl-IAA) and 4-methylindole-3-acetic acid (4-Me-IAA) at an early reproductive development stage of wheat (Triticum aestivum L.) canola (Brassica napus L.) and field pea (Pisum sativum L.), will increase the seed yield under normal and heat stress environments, when the stress occurs during the reproductive stage. In wheat, cultivar CDC Go was the most responsive to auxins, with 4-Cl-IAA increasing grain yield under non-stress and heat stress controlled environment conditions and field conditions. 4-Cl-IAA and 4-Me-IAA increased seed yield in pea, and 4-Cl-IAA in canola, under controlled environment conditions; however, 4-Me-IAA appeared to be more effective at increasing seed yield under field conditions for these crops. Further studies are required to broaden our knowledge of the conditions and genotypes necessary to obtain optimal auxin response for increased seed yield under a variety of environmental conditions.