贵州本土半野生番茄砧木介导ABA生物合成信号通路调控植株耐旱性的机理研究

随着全球气候变暖，干旱胁迫成为限制番茄等蔬菜作物安全生产的重要因素之一。前期研究发现嫁接贵州本土半野生番茄GZ-01砧木其可以提高植株的耐旱性。为探究野生番茄GZ-01增强植株耐旱性的分子机理，以半野生番茄GZ-01砧木和红果番茄为试验材料，结合形态生理学和分子生物学，比较嫁接番茄和自嫁接番茄植株对干旱胁迫的响应。结果表明，干旱胁迫下，与自嫁接植株R/R相比，GZ-01/R嫁接植株细胞膜的损伤显著降低，植株的抗氧化能力、干物质累积量、CO2同化率和水分利用率显著提高，离体叶片失水率显著降低，下气孔闭合比率显著提高，脱落酸（ABA）合成相关基因表达量和ABA含量显著提高。嫁接植株GZ-01/R可能通过调控ABA的合成来影响气孔开闭，调控叶片失水率，提高植株水分利用率，从而影响植株对干旱胁迫的响应。本研究为开发利用贵州本土半野生番茄资源奠定了基础，为增强干旱胁迫和分子调控网络途径提供了理论支撑。

Mechanism of Guizhou Native Semi-wild Tomato Rootstocks Mediates ABA Biosynthesis Signaling Pathway to Regulate Plant Drought Tolerance

With global warming， drought stress has become one of the important factors restricting the safe production of tomato and other vegetable crops. The use of rootstocks from wild resources is a low-cost and efficient way to improve plant disease resistance and stress resistance. Previous studies have found that grafting GZ-01 rootstock， a native semi-wild tomato in Guizhou， can improve the drought tolerance of plants. In order to explore the molecular mechanism of GZ-01 on enhancing drought tolerance of wild tomato plants， the response of grafted tomato and self-grafted tomato plants to drought stress was compared by using semi-wild tomato rootstock GZ-01 and red fruit tomato as experimental materials， combined with morphophysiology and molecular biology. The results showed that under drought stress， when compared with the R/R of self-grafted plants， the damage of cell membranes of GZ-01/R grafted plants was significantly reduced， the antioxidant capacity， dry matter accumulation， CO₂ assimilation rate and water utilization efficiency of plants were significantly improved， the water loss rate of ex vivo leaves was significantly reduced， the lower stomatal closure ratio was significantly increased， and the expression of ABA synthesis-related genes and ABA content were significantly increased. Grafted plant GZ-01/R may affect the opening and closing of stomata， regulate leaf water loss， and improve plant water utilization by regulating the synthesis of ABA， thereby affect the response of plants to drought stress. This study lays a foundation for the development and utilization of native semi-wild tomato resources in Guizhou， and provides theoretical support for enhancing drought stress and studying molecular regulatory network pathways of stress resistance.