Physiological Effects of High Temperature Stress in Some Cucurbit Plants

Abstract

Some cucurbit plants (Cucumis sativus L., Cucurbita pepo L., Cucumis melo L. and Citrillus lanatus L.) were used for investigating some physiological changes and protein patterns under heat stress in plants. Leaf samples were exposed tohigh temperatures as follows 35, 40, 45, 50, 55 and 60°C. Percentage of ion leakage, chlorophyll content, leaf relative water content (RWC) and loss of turgidity, total soluble protein (TSP) content and protein profiles were determined in leaf samples kept at each temperature stage for 30 minutes. Ion leakage was increased especially 55 and 60°C in all cucurbits parallel to the temperature increasement. Total chlorophyll content was decreased slightly in both cucumber cultivars, zucchini, in both melon cultivars and watermelon due to high temperatures. The RWC of cucurbits was decreased on the contrary of the loss of turgidity, which was parallel to the increment of temperatures. While the TSP content in cucumber was decreased with temperature increasement, it was not changed in zucchini and watermelon. In melon cultivars TSP was not noticeably changed until 55°C, but significantly decreased at 60°C. When the SDS-PAGE profiles of cucurbits were examined, many protein bands were observed with sizes ranging from 6.5 kDa to 211 kDa.

Effects of Heat Stress on Some Biochemical Traits of Small Reddish Bean

“…Besides, Ergin et al (2016) indicated that heat stress resulted in new protein bands and decreases/disappearance of some proteins in strawberry plants. In addition, protein bands with molecular weights ranging from 211.0 and 18.9 kDa in watermelon, 158.2 and 21.4 kDa in melon, 84.1 and 16.4 kDa in cucumber, 121.3 and 6.5 kDa in zucchini were detected, however the synthesis of these proteins was lost with increment of temperature (Ergin et al, 2021).…”

“…Tokyol and Turhan (2019) found that the TSP content of green bean genotypes reduced and/or induced with heat stress. Besides, in tomato (Turhan et al, 2021) and cucumber (Ergin et al, 2021) plants fluctuations in the TSP content under high temperatures were reported. Besides, the TSP contents of zucchini plants were not affected by the temperature, while the TSP content of melon plants did not change up to 50°C and then decreased with the increase in temperature (Ergin et al, 2021).…”

“…Besides, in tomato (Turhan et al, 2021) and cucumber (Ergin et al, 2021) plants fluctuations in the TSP content under high temperatures were reported. Besides, the TSP contents of zucchini plants were not affected by the temperature, while the TSP content of melon plants did not change up to 50°C and then decreased with the increase in temperature (Ergin et al, 2021). Protein structure and activity is adversely affected by heat stress (Hasanuzzaman et al, 2013).…”