Relation of Morphological Characters and Shoot Yield in Wheat¹

Abstract

Measurements were made on morphological components of the wheat ( Triticum aestivum L. em Thell) shoot. The relationship of a morphological component and grain yield per shoot was determined for four winter wheat cultivars in Belgium and two sprisg wheat cultivars in Minnesota in various field planting patterns and in various controlled environments. The shoot was the measurement unit in these studies. Measurements of 37 morphological traits including such traits as shoot grain yield; kernel number; lengths, widths and dry weights of leaves, sheaths, and stem segments; dry weights of awns and spikes; flag leaf angle; and heights of insertion of leaves and spikes. The data were analyzed by calculating simple correlation coefficients and by using stepwise regression and factor analyses. All three methods indicated that the characters most closely related to grain yield per shoot were kernel number, awn dry weight, some sheath and stem dry weights, and leaf dry weights, in that order. The number of spikelets ranked between awn dry weight and the stem dry weights in the closeness ot their relationship with yield. Leaf length and width characters, height of insertion of plant organs, and leaf angle were all poorly yanked in comparison to other morphological traits in closeness of association with grain yield per shoot.