大麦芒对籽粒产量的作用

Effect of Barley(Hordeum vulgate)Awns on Grain Yield

1982—1987年剪芒、剪叶试验结果表明,大麦诸光合器官对产量的作用表现为:芒>旗叶>倒2叶>倒3叶。芒的作用因品种类型和灌浆期的气候生态条件不同而异,六棱大麦芒的作用大于二棱大麦。在温度较高,光照充足和雨量较少的年份,芒对粒重的贡献较大;反之,在温度较低,光照不足和雨量较多的年份则较小。灌浆期芒上喷尿素加 KH_2PO_4液体肥料能显著提高芒的光合强度,增加千粒重1.3—3.4克。芒对产量贡献卓越的主要原因在于其光合细胞结构复杂,光合面积大和叶绿素含量多。

Awn-cutting and defoliation experiments in barley made from 1982 to 1987 showed that the effect of different photosynthetic organs on grian yield followed the fol- lowing order:awn>flag leaf blade>second leaf blade from the top>third leaf blade from the top.The effect of awn varied with barley types and ecoclimatic conditions during kernel filling stage.It was greater in six-rowed barley than in two-rowed bar- ley.The contribution of awn to grain weight in the years with higher temperature, abundant sunlight and less rainfall is greater than that in the years with lower tempera- ture.insufficient sunlight and more rainfall.At the kernel filling stage.spraying liquid fertilizer of urea mixed with KH_2PO_4 onto awns could improve photosynthetic capacity considerably.with an increase of 1.3-3.4g per 1000 grains.The principal machanism of the excellent contribution of awn to grain yield lies in their complex structure of assimilation cells.larger photosynthetic area and higher content of chlorophyll.