Investigation of Vegetative High Temperature Tolerance of Some Cotton (Gossypium hirsutum L.) Varieties

Abstract

Our aims to scan the harmful effects of high temperature stress on vegetative development on cotton varieties registered in our country. The experiment was established in the GAPUTAEM trial area in 2020, with 4 blocks according to the Augmented design. Six standards (Tamcot Spnhix, SJU86, AGC208, STV468, ST474, Carmen) and 88 cotton varieties registered in the national variety list were used as trial material. In this study, relative cell injury rate (RCI) and leaf high temperature stress index values (LHTSI) were investigated. Our investigation results show cell membrane damage (%RCI) varied between 41.81% and 74.84%. While the average of the standards used in the experiment was 68.15%, the overall average was found to be 62.42%. Leaf high temperature stress index (LHTSI) values varied between 0.48 and 1.85, while the LHTSI average of the standards was 0.98, and the overall LHTSI average of the experiment was found to be 1.02. It was determined that there was a wide variation among the genotypes screened for vegetatively high temperature stress. Using LHTSI and RCI features, it has been concluded that it is an important, effective, easy, and applicable selection criterion for screening genotypes regarding tolerance or sensitivity to high temperature stress vegetatively in cotton plants. Applying these two parameters together is recommended to obtain more accurate results. It was determined that only the Teksa415 cotton variety was vegetatively tolerant. Vegetatively, 31 cotton genotypes were found in the medium tolerant group and 62 cotton genotypes in the sensitive group.