为探究热激处理对甜瓜未授粉子房培养中胚珠膨大发育与内源激素的影响，以期为揭示胚珠膨大和单倍体培养的机理研究奠定基础。以热激和对照培养不同天数的甜瓜未受粉子房为试材，对胚珠膨大率进行动态监测，并采用UPLC-ESI-MS/MS法测定顺式玉米素核糖核苷(CZR)、赤霉素3(GA3)、反式玉米素(ZT)、吲哚-3-乙酸(IAA)及脱落酸(ABA)含量，并分析了这5种内源激素与胚珠膨大发育的关系。结果表明，与对照25 ℃室温培养相比，32 ℃热激处理4 d有利于胚珠的膨大及内源激素的积累，且在胚珠膨大期5种内源激素的变化趋势一致，均为递增。各内源激素间的比例关系处于动态变化中，且在整个膨大期，热激处理下IAA/(ZT+CZR)、IAA/ABA和IAA/GA3均较对照25 ℃室温培养高；胚珠膨大率与内源激素IAA呈极显著正相关，相关系数达0.818，与ZT、CZR和ABA均呈显著正相关，与(ZT+CZR)/GA3呈显著负相关。

In order to explore the effect of heat shock treatment on ovule expansion and endogenous hormones in unpollinated ovary culture of melon, and to lay a foundation for revealing the mechanism of ovule expansion and haploid culture. The unpollinated ovary of melon cultured for different days under the heat shock and control culture was used as the test material, the ovule expansion rate was monitored dynamically, the contents of cis-zeatin ribonucleoside(CZR), gibberellin 3(GA3), trans-zeatin (ZT), indole-3-acetic acid(IAA) and abscisic acid(ABA) were determined by UPLC-ESI-MS/MS method, and the relationship between these 5 endogenous hormones and ovular expansion was analyzed. The results showed that heat shock treatment was beneficial to ovule enlargement and accumulation of endogenous hormones compared with the control culture at 25℃, and the changes of 5 endogenous hormones in ovule enlargement stage were consistent and increased. The proportional relationship between the hormones was in dynamic change, and the ratios of IAA/(ZT+CZR), IAA/ABA and IAA/GA3 under heat shock treatment were higher than the control throughout the expansion period. The ovule expansion rate was significantly positively correlated with the endogenous hormone IAA(the correlation coefficient was 0.818), and was significantly positively correlated with ZT, CZR and ABA, but was negatively correlated with (ZT+CZR)/GA3.

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甘肃省农业科学院中青年基金(2020GAAS44)；甘肃省农业科学院生物育种专项(2022GAAS05)。