Genetic analysis of peduncle length in durum wheat (Triticum durum Desf.) under diverse environments

Abstract

Recent breakthroughs in wheat production are attributed to the development of physiologically and morphologically efficient varieties, which can utilize light, nutrition and water more effectively to give better yield per unit area. Breeding on the basis of economic traits has received attention for a long time and this factor has been fully utilized in bread wheat. Presently the yield level has almost reached a plateau. Further breakthroughs in yield level may be obtained by exploiting the genetic information for important physiological traits related to yield. It appears that photosynthesis in the peduncle may also contribute to the dry matter of the grain of wheat [1] and therefore, the surface of the peduncle may have some relation to yield. The internodes remain usually very short as compared to the tall varieties, while the total number of leaves remain more or less equal. Therefore, due to shorter internodes, particularly the last internode (peduncle) and more number of leaves in a limited culm length, the sunlight does not properly penetrate throughout the plant. In this situation, longer peduncles will help the plant to receive more of sunlight and increase the total photosynthetic area and Ultimately the end product. Studies on peduncle length would be extremely useful for the development of high yielding dwarf and semi dwarf durum wheat (Triticum durum Desf.) varieties having long peduncle length for both irrigated and unirrigated conditions. Limited work has been done on this trait particularly in durum wheat. In view of the above, this study was undertaken in twelve generations to estimate the nature and relative magnitude of various gene effects operative in the inheritance of peduncle length in three inter-varietal crosses of durum wheat grown under diverse environments by using generation means analysis for formulating effective selection procedures to improve this trait.