花前干旱锻炼对避雨栽培番茄花后渍水逆境下品质的影响机制及效应

Soil water environmental stress is one of the most important factors limiting quality in tomato production. In the study, cylinder,pit and plot experiment for rain-shelter-cultivation tomato will be conducted by designing the treatments of drought hardening before bloom and fruit-bearing and waterlogging after the stage combined with fruit analysis in laboratory and model validation. The research aims to explore stoma regulation, process of water use and physiological changes of tomato under the condition of drought hardening and waterlogging after bloom and fruit-bearing stage,explicate the action mechanism and effect of drought hardening and waterlogging after bloom and fruit-bearing stage on the element of water balance, growth index and yield of crop,study the adaptations of root activities and morphological characteristics to drought hardening and its influence on resistance of waterlogging after bloom and fruit-bearing stage, analyse the response of fruit quality, such as soluble solids, vitamin c content, edible rate and so on, define the ornament effect of waterlogging after bloom and fruit-bearing stage on morphological characters arising from drought hardening,set forth physiological and cultivation science mechanism of effect on fruit quality for superposition between drought hardening and waterlogging after bloom and fruit-bearing stage. Based on thinking over water-saving, good quality and high yield, the model will be established to evaluate control indicator combination indicating degree of drought and waterlogging by means of principal component analysis and projection pursuit. The result will have important theoretical and practical value in deeply exploring physiological and ecological mechanism of the process of fruit quality formation in south China and optimal cultivation techniques for resistance to waterlogging.

土壤水分逆境是限制番茄品质形成的重要生态因子。本研究拟选用避雨环境下番茄为研究对象，通过设置花前干旱锻炼及花后渍水逆境叠加处理，采用筒栽、测坑和小区定量定位系统监测试验和室内品质分析与模型验证相结合的方法，研究干旱锻炼及花后渍水下作物气孔调控与用水过程及生理状况，明确干旱锻炼及花后渍水对水平衡要素、生长指标和作物产量的调控效应及作用机制；揭示根系活力与形态对干旱锻炼适应性变化及其对花后抗渍能力的影响，阐明花后渍水胁迫对干旱锻炼诱导特征形状的修饰效果，分析果实可溶性固形物、Vc含量、可食率等品质参数对干旱锻炼及花后渍水逆境的响应规律；探讨干旱锻炼及花后渍水逆境叠加品质效应产生的生理与栽培学机制。在考虑节水、优质和高产的基础上，运用主成分分析和投影寻踪构建避雨环境下干旱和渍水逆境控制指标组合评价模型。研究结果对于深入探究南方番茄品质形成的生理生态机制和抗渍调优栽培具有重要理论和实践意义。

为了探索适合支持渍水逆境条件下作物的生产途径，挖掘作物自身的抗渍能力，本试验选取番茄作为研究对象，通过设置花前干旱锻炼及花后渍水逆境的叠加处理，将筒栽、小区试验与室内品质分析相结合，观测了干旱锻炼及花后渍水逆境下番茄的生理指标、生态指标；分析了番茄果实的品质、产量等对干旱锻炼及花后渍水逆境的响应规律。以节水、优质、高产为基础，运用综合主成分分析和灰色关联法构建避雨环境下干旱和渍水逆境控制指标组合评价模型。本研究可为探究南方地区番茄抗渍调优栽培提供技术支撑和理论依据。研究结果如下：. (1) 苗期干旱锻炼促进了花后渍水逆境下番茄的生长发育和干物质的积累。苗期干旱锻炼可以减轻花后渍水对生长发育和植株光合作用的抑制，增加干物质积累；苗期干旱锻炼会抑制由渍水引起的蒸腾速率、气孔导度的增加，提高水分利用效率。. (2) 花前干旱锻炼提高花后抗渍的生理学机制。苗期干旱锻炼能够提高花后渍水下叶片中蛋白、SOD和CAT含量和活性，从而可以保证番茄叶片正常生长；干旱锻炼能够调整光合作用产物在不同组织之间的分配比例，从而起到优化植株结构更好适应渍水胁迫的作用。. (3) 苗期干旱锻炼能够促进花后渍水逆境下番茄的保质稳产。苗期对干旱不太敏感，在苗期进行干旱锻炼对产量的影响较小，同时还可以提高土壤水分利用效率(WUE)，苗期干旱锻炼对花后渍水造成的番茄品质、产量下降表现出一定的拮抗效应。综合考虑，花前干旱锻炼能够促进花后受渍番茄的保质稳产。. (4) 基于节水、优质和高产下旱渍组合的优选模型。以品质综合主成分、产量、水分利用效率和灌溉水利用效率为评价指标，利用灰色关联法构建了旱渍指标组合评价模型，对全部旱渍组合处理进行优劣排序，确定了苗期60%F干旱锻炼、花后-30cm渍水胁迫的处理为最佳旱渍组合方式。