Abstract:
Plants in nature often experience multiple stresses at the same time, including heat stress, which is known to negatively impact plant growth and development. However, the potential of amino acid application to alleviate abiotic stress in plants has not been extensively researched. In this study, we investigated the effect of exogenously applied L-methionine on two cultivars of sunflower (Helianthus annuus L.) grown under heat stress in a pot experiment. The cultivars, Gulshan and Hysu-39, were subjected to seven levels of methionine (control, water, 20, 40, 60, 80, and 100 mg/L) at 45°C as stress and 25°C as control conditions. Our results showed that heat stress significantly reduced the shoot and root length, shoot and root fresh and dry weight, chlorophyll content, phenolic and flavonoid contents in both cultivars of sunflower. Concurrently, there was a significant increase in malondialdehyde (MDA) and hydrogen peroxide (HO) concentration. However, foliar application of methionine effectively reduced the MDA and HO contents under heat stress and increased the shoot and root fresh and dry weight, shoot and root length, chlorophyll content, as well as flavonoid and phenolic contents in both cultivars. Overall, our findings suggest that all levels of methionine helped mitigate heat stress in sunflower cultivars compared to the control, with 100 mg L-1 of methionine being the optimal dose. This level of methionine not only reduced heat stress but also improved the morphological and physiological characteristics of the plants. Furthermore, Hysu-39 showed greater tolerance to heat stress compared to Gulshan.
Page(s):
139-139
DOI:
DOI not available
Published:
Journal: Abstract Book on Second International Conference on Recent Approaches in Plant Sciences (RAPS-23) 4-5 May 2023 , Volume: 0, Issue: 0, Year: 2023
Keywords:
Sunflower
,
heat stress
,
Tolerance
,
Lmethionine
,
phenolic content