高温胁迫下不同皮色西瓜耐热性评价研究

Evaluation on heat tolerance of watermelon varieties with different peel colors under high temperature stress

【目的】研究高温胁迫条件下不同皮色西瓜耐热性,为耐热西瓜品种育种提供理论依据。【方法】采用大田试验,设闷棚和普通大棚(对照)两种处理,测定不同皮色西瓜相关生理和品质指标,采用隶属函数方法对其耐热性进行综合评价。【结果】与对照处理相比,闷棚处理不同西瓜品种的叶绿素总含量、MDA、脯氨酸含量均出现不同程度下降;POD活性均出现不同程度上升,SOD活性均出现不同程度下降,而CAT活性既有上升、又有下降;果实单瓜重、硬度、可溶性固形物含量、Vc和可溶性蛋白含量均出现不同程度下降。不同西瓜品种隶属函数平均值由大到小依次为R2、R3、R1、R11和R6。【结论】明花皮色的西瓜耐热性最好,暗花和墨绿色皮色的西瓜耐热性次之,黄皮和绿皮西瓜耐热性较差。

[Objective]The experiment was conducted to study the heat tolerance of watermelon with different peel colors under high temperature stress in order to provide theoretical foundation for heat-resistant watermelon breeding. [Method]Field experiment was used and two treatments （closing greenhouse and the control normal greenhouse） were designed. The physio- logical, biochemical of leaves and quality indexes of watermelon were determined. The heat tolerance of watermelon was com- prehensively evaluated by the method of membership function. [Result]Compared with the control, the total chlorophyll, MDA and proline content, and SOD activity in leaves, as well as mean fruit weight, hardness, soluble solid content, Vc content and soluble protein content of all watermelon varieties in closing greenhouse decreased in degrees. However, POD activity of all watermelon varieties in closing greenhouse increased compared with the control. CAT activity showed increase or decease in different watermelon varieties. The average of membership function in different watermelon varieties was as follows： R2〉R3〉 RI〉R11〉R6. [Conclusion]The watermelon variety with obvious stripe peel had best heat resistance, followed by the watermel- on with dim stripe peel and black green peel, and the heat resistances of watermelon with yellow and green peel were worse.