EFFECT OF WEATHERING DURING DELAYED HARVEST ON TEST WEIGHT, SEED SIZE, AND GRAIN HARDNESS OF WHEAT
Five cultivars of wheat (Triticum aestivum L.) were evaluated for effects of weathering by subjecting windrowed grain to varying periods of exposure in a 2-yr study. Moderate amounts of precipitation caused a significant reduction (5%) in test weight affecting density and packing efficiency about equally. Cultivars differed in test weight loss with Neepawa showing the largest reduction of 2.9 and 4.2 kg hL−1 in successive years. Cultivars also differed in susceptibility to bleaching, the primary cause of grade loss. The 1000-kernel weights decreased significantly (1.4%) in only 1 yr. Grain hardness decreased approximately 8% with delayed harvest at similar rates for all cultivars. The hard-grained Glenlea and RL4137 were the most resistant to test weight loss and bleaching, indicating that selection for improvement might be possible.Key words: Harvest delay, weathering, wheat, test weight, seed size, grain hardness