Grain Yield and Protein Relationships in a Wheat Cross¹

Abstract

The relationships between grain yield and protein content were examined in segregating populations from a cross between a locally‐adapted high‐yielding, low protein wheat cv. ‘Olympic’ ( Triticum aestivum L.) and a lower‐yielding high protein cv. ‘Kenya B.’ Segregation for grain protein content in the F 3 was continuous with no dominance. In the F 4 and F 5 , it was again continuous but there was partial dominance for low grain protein. Yield segregation in the F 4 and F 5 was continuous with partial dominance for low yield. Grain yield and protein content in the F 4 and F 5 populations of the cross Olympic × Kenya B were found to be negatively correlated [r = ‐0.13 NS for the F 4 and r = ‐ 0.58 (P < 0.01) for the F 5 ]. While low protein and high yield were significantly associated in the F 5 it would appear that there were no strong genetic limitations to improvement in protein percentage of the cv. Olympic at its present level of yield.