双季板栗休眠期至花期芽体或花序内源激素的变化

Research on the changes of endogenous hormones during dormancy to flowering of Shuangji chestnut

【目的】研究双季板栗休眠至花期(雌花序出现)结果母枝混合芽和结果枝基部叶芽、纯雄花序、混合花序内源激素含量及其比值,为板栗花芽分化调控提供理论参考。【方法】在双季板栗休眠期前期每隔30 d、休眠末期至芽体萌动每隔15 d采集结果母枝混合花芽,在萌动至花期每隔3~5 d采集结果枝基部叶芽、混合花序和纯雄花序,测定ZR、IAA、GA 3和ABA含量,分别以C(ZR)、C(IAA)、C(GA 3)和C(ABA)表示。【结果】各时期IAA和ABA含量均高于ZR和GA 3含量,C(GA 3)/C(ZR)和C(IAA)/C(ABA)值均显著高于C(GA 3)/C(IAA)、C(GA 3)/C(ABA)、C(ZR)/C(ABA)和C(ZR)/C(IAA)值。在休眠至萌动期,混合花芽IAA含量从11.810 ng/g上升至36.770 ng/g,ABA含量从148.312 ng/g下降至64.938 ng/g,IAA含量在萌动前极显著升高,ABA含量极显著下降;C(IAA)/C(ABA)值从0.072显著上升为0.566,C(ZR)/C(IAA)和C(GA 3)/C(IAA)值下降最显著,分别从0.721和0.445下降至0.263和0.158。在萌动至花期,混合花序和结果枝基部叶芽IAA含量呈抛物线变化,纯雄花序呈不规则抛物线变化,均于3月30日达到峰值,分别为102.801、89.466、112.850 ng/g;各部位ABA含量呈波浪形变化,GA 3与ZR含量呈无明显规律的波动变化;混合花序和纯雄花序C(GA 3)/C(ZR)和C(GA 3)/C(IAA)值整体呈上升趋势,在现雄期至现雌期大幅上升并表现为混合花序C(GA 3)/C(ZR)和C(GA 3)/C(IAA)值高于纯雄花序;结果枝基部叶芽、纯雄花序和混合花序C(GA 3)/C(ABA)、C(IAA)/C(ABA)和C(ZR)/C(ABA)值的变化规律相似,在开始出现纯雄花序后,纯雄花序C(GA 3)/C(ABA)、C(ZR)/C(ABA)和C(IAA)/C(ABA)值均高于混合花序;C(ZR)/C(IAA)值与其他指标值的变化规律不同。【结论】高C(IAA)/C(ABA)值、低C(ZR)/C(IAA)和C(GA 3)/C(IAA)值共同作用,在促进芽萌动方面可能起重要作用。C(GA 3)/C(ZR)、C(GA 3)/C(ABA)、C(ZR)/C(ABA)和C(IAA)/C(ABA)值可能影响板栗的花性,高C(GA 3)/C(ZR)值、低C(GA 3)/C(ABA)值、低C(ZR)/C(ABA)值和低C(IAA)/C(ABA)值有利于雌花形成。

【Objective】The content and ratio of endogenous hormones in the mixed buds of bearing mother branch and leaf buds,pure male inflorescence and mixed inflorescence at the base of bearing branch were studied from dormancy to flowering(when the female inflorescence appeared),which could provide theoretical basis for the regulation of flower bud differentiation in chestnut.【Methods】The mixed flower buds of the parent branches(every 30 days in the early stage of dormancy,every 15 days from the end of dormancy to the sprouting),the leaf buds,mixed inflorescences and pure male inflorescences of the base branches(every 3-5 days from the sprouting to the flowering)were collected to measure and analyze the contents of ZR,IAA,GA 3 and ABA.【Results】The contents of IAA and ABA were higher than ZR and GA 3,and the values of C(GA 3)/C(ZR)and C(IAA)/C(ABA)were significantly higher than C(GA 3)/C(IAA),C(GA 3)/C(ABA),C(ZR)/C(ABA)and C(ZR)/C(IAA)in each period.From dormancy to germination,the IAA content of mixed flower buds increased from 11.810 ng/g to 36.770 ng/g,and the ABA content decreased from 148.312 ng/g to 64.938 ng/g,IAA content increased significantly before initiation,while ABA content decreased significantly;C(IAA)/C(ABA)value increased significantly from 0.072 to 0.566,C(ZR)/C(IAA)and C(GA 3)/C(IAA)values decreased most significantly,respectively from 0.721 to 0.263,and 0.445 to 0.158.In the period of germination to flowering,the IAA content of mixed inflorescences and leaf buds showed parabola changes,while pure male inflorescences showed irregular parabola changes,all reaching the peak on March 30th,which was 102.801,89.466,112.850 ng/g,respectively;the ABA content of each part showed a wavy change,while GA 3 and ZR content variated without obvious change rules;however,the C(GA 3)/C(ZR)and C(GA 3)/C(IAA)values of mixed inflorescence,pure male inflorescence showed an overall upward trend,and the C(GA 3)/C(ZR)and C(GA 3)/C(IAA)values of mixed inflorescence were significantly higher than that of pure male inflorescence from androgyny to the present female,showing that the C(GA 3)/C(ZR)and C(GA 3)/C(IAA)values of mixed inflorescence were higher than that of pure male inflorescence.The changes of C(GA 3)/C(ABA),C(IAA)/C(ABA)and C(ZR)/C(ABA)values of leaf bud,pure male inflorescence,mixed inflorescence were very similar.The C(GA 3)/C(ABA),C(ZR)/C(ABA)and C(IAA)/C(ABA)values of pure male inflorescence were higher than that of mixed inflorescence(after the appearance of pure male inflorescence),but the changes of C(ZR)/C(IAA)values were different from those of other indexes.【Conclusion】High ratios of C(IAA)/C(ABA),low ratios of C(ZR)/C(IAA)and C(GA 3)/C(IAA)may play an important role in promoting bud initiation.The values of C(GA 3)/C(ZR),C(GA 3)/C(ABA),C(ZR)/C(ABA)and C(IAA)/C(ABA)may affect the flower quality of Chinese chestnut.High C(GA 3)/C(ZR),low C(GA 3)/C(ABA),C(ZR)/C(ABA)and C(IAA)/C(ABA)ratio are beneficial to the formation of female flower.