不同基因型燕麦内源激素与灌浆期生理特性之间的关系

Relationship between endogenous hormones and physiological characteristics of different genotype oats at filling stage

为探究内源激素含量对燕麦灌浆过程的影响,分别于2020和2021年,以9个不同基因型的燕麦品种为试验材料,设置大田试验,测定灌浆粒重、灌浆期光合特性、旗叶碳代谢酶(蔗糖磷酸合成酶SPS、蔗糖合酶SS)活性、生长素(IAA)、赤霉素(GA_(3))、玉米素核苷(ZR)、脱落酸(ABA)含量及成熟期粒重,通过方差分析和聚类分析,探究不同基因型燕麦灌浆期生理特性、内源激素差异。结果表明:不同品种间,内源激素含量及其他生理特性差异均达显著水平(P<0.05),按照灌浆粒重,将供试的9个品种分为灌浆较强和较弱两类,其中灌浆较强品种到达灌浆盛期的时间较早,灌浆启动时间也早于其他品种;灌浆粒重拟合程度较好,灌浆过程中的净光合速率、碳代谢酶活性较高,粒重优于其他品种;灌浆较强品种单穗粒重较灌浆较弱品种高11.8%~176.5%;灌浆较强品种旗叶IAA、GA_(3)、ZR含量较灌浆较弱品种高12.6%~118.2%、7.2%~98.0%、21.4%~72.2%,(GA_(3)+ZR+IAA)/ABA较灌浆较弱品种高39.3%~311.9%。在各内源激素水平协调的前提下,IAA、GA_(3)含量与灌浆粒重拟合程度均呈极显著正相关,直接影响灌浆粒重,且间接影响Pn和SPS活性,调控灌浆过程中蔗糖的合成,进而影响粒重。综上,在燕麦灌浆过程中,旗叶IAA、GA_(3)含量较高对粒重有积极的影响。

In order to explore the effects of endogenous hormone content on the grain-filling process of oat,9 oat varieties with different genotypes were selected as experimental materials in 2020 and 2021.Field experiment was conducted to determine the grout grain weight,photosynthetic characteristics,leaf carbon metabolizing enzymes(sucrose phosphate synthase SPS,sucrose synthase SS)activity,auxin(IAA),gibberellin(GA_(3)),zeaxin nucleoside(ZR),abscisic acid(ABA)contents and grain weight.The differences in physiological characteristics and endogenous hormones among different genotypes of oat at filling stage were investigated by variance analysis and cluster analysis.The results showed that:There were significant differences in the content of endogenous hormones and other physiological characteristics among different varieties(P<0.05).According to the grout grain weight,oat varieties were divided into strong grout varieties and weak grout varieties.Among them,the varieties with stronger grain filling reached the peak filling stage earlier,and the grain filling started earlier than other varieties;grain weight fitting degree was better,the net photosynthetic rate and the activity of carbon metabolism enzymes during the grain filling process were higher,and the grain weight was better than other varieties.The grain weight per panicle of the varieties with stronger grain filling was 11.8%to 176.5%higher than that of the varieties with weak grain filling;the contents of IAA,GA_(3) and ZR in flag leaves of the strong grouted cultivars were respectively 12.6%to 18.2%,7.2%to 98.0%,and 21.4%to 72.2%higher than those of the weak grouted cultivars.The contents of(GA_(3)+ZR+IAA)/ABA were 39.3%to 311.9%higher than those of the weak grouted cultivars.Under the premise of the coordination of endogenous hormone levels,the contents of IAA and GA_(3) and grouting grain weight fitting degree displayed very significant positive correlation,which directly affected the grout grain weight,indirectly affected the activities of Pn and SPS,and regulated the synthesis of sucrose during grain filling,thereby affected the grain weight.In conclusion,during the grain filling process of oat,the appropriately increasing in the contents of IAA and GA_(3) in leaves has a positive effect on grain weight.