The difference in the formation of thermotolerance of two cotton cultivars with different heat tolerance. Issue 1 (2nd January 2020)

• Record Type: Journal Article
• Authors: Xu, Wenzheng; Zhou, Zhiguo; Zhan, Dong; Zhao, Wenqing; Meng, Yali; Chen, Binglin; Liu, Weihu; Wang, Youhua
• Is Part Of: Archives of agronomy and soil science. Volume 66:Issue 1(2020)
• Page Start: 58
• Page End: 69
• Publication Date: 2020-01-02
• Subjects: Cotton -- heat stress -- genotype -- leaf subtending the cotton boll -- photosynthesis; Horticulture -- Periodicals; Soils -- Periodicals; 630.5
• DOI: 10.1080/03650340.2019.1593967
• Languages: English
• ISSNs: 0365-0340

Abstract

ABSTRACT: In order to study the mechanism of thermotolerance of cotton cultivars with different heat tolerance, the response of yield component and photosynthesis to short-term heat stress (HT; average temperature 34°C) was studied. Pot experiments were carried out in 2015 and 2016 by using cotton cultivar PHY370WR (heat tolerant cultivar) and Sumian15 (heat susceptible cultivar). Results showed that heat (34°C) treatment resulted in a significant ( p < 0.05) reduction in cotton yield. Path analysis showed that the direct path coefficient (0.89) of boll weight was higher, compared with the boll number (0.46). With high-temperature stress, it was the difference of boll weight reduction contributed the majority to the difference of yield reduction between cultivars, not the difference of boll number reduction. Different decrease in photosynthesis between cultivars leads to the different decline in boll weight. Different thermotolerance between the two cultivars were as follows: the heat tolerant cultivar could maintain higher photosynthesis rate under HT, and it could recover more quickly and highly in photosynthesis than the heat susceptible cultivar. More importantly, the leaf functional period of heat tolerant cultivar was less shortened by HT than that of heat susceptible cultivar.