Developmental Patterns in Five Spring Wheat Genotypes Varying in Time to Maturity1

Abstract

A better understanding of the developmental aspects of time to maturity may assist in developing early maturing cultivars with acceptable grain yield in spring wheat, Triticum aestivum L. The objectives of this study were to determine the developmental patterns in five spring wheat genotypes as well as the relationships among developmental periods and certain morphological traits. This study was conducted at the University of Saskatchewan in 1982,1983, and 1984. In all field experiments, main shoots of randomly selected plants were used for data collection. ‘Ingal’, ‘Ken 149’, and ‘Potam’ were early maturing genotypes from Alaska, Manchuria, and Mexico, respectively, while ‘Glenlea’ and NB402 were late maturing genotypes from the Canadian Prairies. In general, the difference between the three introduced genotypes and the two Canadian genotypes in time to maturity could be attributed to the difference in duration of the preanthesis period. Ingal required fewer growing degree‐days to reach maturity than Ken 149 and Potam, due to a shorter grain‐filling period. In spite of their diverse origin, Ken 149 and Potam were similar in time to maturity as well as in the other 15 traits evaluated. Glenlea and NB402 were similar in time to maturity. However, compared with NB402, Glenlea spent less time in both the vegetative and spikelet initiation periods and more time in the spike growth period. Differences in developmental patterns among the genotypes were related to differences in number of leaves, number of spikelets, rate of spikelet initiation, spike length, and kernel weight.