Coleoptile Length and Emergence of Amigo 1AL.1RS Semidwarf Wheats

Abstract

This study compared growth chamber coleoptile length and field emergence of wheat backcross lines, that have the Amigo 1AL.1RS wheat-rye translocation, to those of their recurrent semidwarf cultivar parents. Field emergence from 4, 6 and 8 cm was determined in 1989, 1990 and 1991. Fourteen of 22 backcross lines had significantly longer coleoptiles than their recurrent parent, but those of only one were more than 10% longer. None had shorter coleoptiles. Differences in emergence among genotypes were substantial only in 1990, significant among planting depths in all experiments, but the genotype x planting depth interaction was not significant in all experiments. Differences in coleoptile lengths accounted for no more than 10% of the variation in emergence percentage across all treatments, but in 1990 variation in coleoptile length accounted for 36% of the variation in emergence percentage from the 8 cm depth, 81% of the variation in emergence among genotypes, and 98% of the variation among seed source emergence means. Although generally unrelated, seed weight in 1991 accounted for 64% of the variation in emergence of genotypes from the 8 cm depth. The Amigo 1RS rye segment had a small positive effect or no effect on coleoptile length and seedling emergence.