摘花处理对大豆花荚发育和产量的影响

Effect of Defloration on Flowering,Podding and Yielding in Soybean

为了探究大豆的开花潜力及损失补偿能力,本研究以生育期相近但结荚习性不同的中黄13、邯豆5号和Williams 82为材料,设置短期连续摘花处理(3,5和7 d)和长期连续摘花处理,研究摘花处理对大豆开花动态、结荚和产量的影响。结果表明:(1)同期播种条件下,大豆材料的自然开花动态与结荚习性有关,但其总花数差异不大。其中,有限结荚习性的中黄13日开花数先升后降,开花持续日数较短;而亚有限结荚习性的邯豆5号和Williams 82日开花数相对平稳,开花持续日数较长;(2)长期摘花处理能刺激植株不断催生花芽,以补偿摘花损失,导致开花期明显延长。在长期摘花处理下中黄13和邯豆5号植株总花数分别是对照植株的2.46和3.07倍,新生花朵具备正常的生殖能力。自然条件下长期摘花处理可导致茎秆及叶片持绿、底部节位叶腋出现次生茎叶等类似症青的症状;(3)亚有限结荚习性品种进行短期摘花处理,仅刺激摘花节位不断生成新花朵,但对植株相邻节位的开花数没有影响。邯豆5号和Williams 82表现出短期摘花减产或增产的现象,与新生花数、花荚转化率和粒重的变化幅度差异有关。总之,大豆整株花序发育的潜力巨大,一旦花朵无法完成授粉受精而脱落(摘花处理),植株可以催生新花加以补偿,但植株的生育期将延迟。在北方大豆生产中,植株生育期延迟与秋季低温是难以调和的矛盾。研究结果可为大豆开花期非生物逆境的相关研究提供参考。

In order to explore the potential and compensation ability of soybean flowering,three soybean cultivars with different termination habit and similar growth period,Zhonghuang 13(with determinate habit),Handou 5 and Williams 82(with sub-indeterminate habit),were used as experimental materials.The continuous defloration treatments of short-term(3,5 and 7 d)and long-term were set to evaluate the effect of artificial defloration on flowering dynamics,podding,and yielding in soybean.The results showed that:(1)The total flower number was similar among the materials sown at the same time,but various natural flowering dynamics was closely related to stem termination habits i.e.,Zhonghuang 13 had a flowering tendency of sharp-rise-then-drop with short duration.However,Handou 5 and Williams 82 had relatively stable flowering with longer duration;(2)In the long-term defloration treatments,new flowers were grown continuously to compensate defloration loss,and the flowering period was prolonged as well.The total number of flowers of Zhonghuang 13 and Handou 5 were 2.46 and 3.07 times in the long-term defloration treatments compared to the corresponding controls,respectively.Moreover,the palingenetic flowers had normal reproductive ability.Under the natural condition,long-term defloration treatment resulted in stay-green syndrome,and the secondary stems grew from leaf axils at the lower nodes;(3)The short-term defloration treatments stimulated new flower genesis in the treated nodes,and without effect on adjacent nodes in sub-terminate soybean varieties.The opposite effect of short-term defloration on yield in Handou 5(yield loss)and Williams 82(yield gain)was resulted from difference of palingenetic flowers,the flower-pod transformation rate,and seed weight.Therefore,soybean defloration,because of pollination and fertilization(simulated with artificial defloration),can be compensated by palingenetic flowers with enormous potential,which accompanied by prolonged growth period.However,the prolonged growth period of soybean is contradicted with autumn chilly weather in the northern China.These results can be referred to the related research on environmental stress in soybean flower stage.