Differential Impact of CBL3-1 and CBL3-2 Gene Silencing on Tomato Growth and Responses under Drought Stress

Abstract

Drought and salt stress impact crop yield in sustainable agriculture. Understanding plant responses at the molecular level is essential for developing drought-tolerant plants. Transcriptome analysis helps identify stress-response genes. Virus-induced gene silencing was used to study gene functionality and plant resistance to drought stress. Therefore, in this study, we investigated the effect of silencing CBL3-1 and CBL3-2 genes on some growth and physiological parameters of leaf discs under drought stress. The results indicated that growth and water content of tomato (Solanum lycopersicum L.) decreased under drought stress in all treatments. Moreover, our findings indicated that silencing of both CBL 3-1 and CBL3-2 genes hurt growth and increased the McKinney index and ROS content under drought stress. However, silencing CBL3-1 had a more significant negative effect than CBL3-2. The suppression of CBL3-1 expression led to a hypertensive response to drought stress and significantly decreased FW, total chlorophyll and carotenoids, while increased the McKinney index and ROS content. Silencing CBL3-1 resulted in the highest ROS, MDA content, and proline accumulation. It should be emphasized that the inhibition of CBL3-1 results in a more significant negative effect than CBL3-2 under conditions of drought stress.