Authors: Hristo Stoyanov
Keywords: Componential analysis, Yield structure, Triticum ×toschevii

The formation of yield and its components is especially important in the breeding of new amphidiploid species. In order to determine the main components of yield in the species Triticum ×toschevii, 12 indices of the spikes were analyzed in three successive growing periods. Componential analysis was done to determine the main components in the formation of the yield’s structural elements. Based on the analyses carried out, the number of grains per spike and 1000 kernel weight were determined as the main structural elements. Indices such as number of spikelets per spike, spike length, and spike length with the awns were of secondary importance. The componential analysis clearly distinguished the structural elements of yield according to the way of their formation. The main components were four and they accounted for over 96 % of the total variation. The indices number of spikelets per spike, spike length, and awnness index were determined as typical vegetative components. The number of grains per spike and all mass indices were formed by the main component and were determined as typical generative indices. The length of spikes with awns and the number of spikelets along the length of the spike were determined by a third component. Such data outlined the high importance of the variation of the generative indices for the size of yield. This imposes the necessity to carry out purposeful selection in the species Triticum ×toschevii, so that it can be efficiently introduced as a cultural plant.Download article