Adaptive ability of CMS-lines in conditions of the Lower Volga region

Abstract

In sorghum hybrids selection the identification of the source material combining high yield and adaptation to abiotic and biotic conditions of cultivation is actual. The methods for determining the adaptive capacity of CMS-lines (coefficient linear regression and variation) make it possible to reveal their response to growing seasons differing in climatic conditions. Observation of grain sorghum plants was carried out in 2009-2018 on the experimental field "Rossorgo". Environmental factors have less impact on the signs: period of "germination-flowering", plant height, length inflorescence, length and width of the largest leaf (V = 5.0-19.8%). The wide variability of characters (V = 13.3-44.3%) was revealed by the intensity of the initial plant growth, the width of the inflorescence, the area of leaf and grain yield. As a result of the regression analysis, lines that are distinguished by their plasticity and phenotypic stability according to a complex of selection traits were found. A2 KVV 114 is highly plastic in terms of its economic characteristics. The CMS lines M35-1A Pischevoe 614 and 9E Pischevoe 614 differ in phenotypic stability in yield (b_i = 1.01-1.07) and plasticity in the length and width of the inflorescence (b_i = 1,40-2.49). Sterile lines A3, A4 and 9E Zheltozernoe 10 are capable of forming a grain harvest in more droughty growing seasons (b_i = 0.80-0.83) and have phenotypic stability of the characteristics: the "germination-flowering” period, the height of plants 30 days after germination and when ripe, the area of the largest sheet. According to the results obtained, it is recommended to include a working collection of maternal forms in the program of crosses in order to obtain productive hybrids that are adapted to the conditions of the Lower Volga region.