湿害胁迫下大麦生长抑制和产量损失的基因型差异

在分蘖期对15份大麦基因型进行12 d 的渍水处理,研究渍水条件下生长抑制和产量损失的基因型差异.结果表明,黄化指数(LCI)虽然不能完全反映所有基因型的产量损失程度,但作为耐湿性的一个指标对大多数基因型是可靠的.在渍水期间和撤水后,大部分大麦基因型新长的叶长和叶宽下降,但93-3143变化不大;渍水处理与对照相比,株高和干重平均降低29.2%和54.4%,基因型间差异显著,Franklin的降幅最大.渍水下导致籽粒产量显著下降,产量构成因子中以穗数下降最为明显,其次是每穗粒数,粒重变化较小,而穗数减少主要是分蘖及其成穗数下降的结果.渍水对产量影响的基因型差异很大,地方品种永嘉红六棱减产最小,两个澳大利亚主栽品种Franklin和Gairdner减产最为严重.产量构成因子对产量的直接通径系数大小依次为:穗数、粒数和粒重,穗数经粒数对产量的影响很小,经粒重的间接通径系数较大且为正值;粒数经穗数对产量的影响亦较小,经粒重的间接通径系数较大且为负值;粒重经穗数和粒数对产量的影响均较大,但作用方向不同.

Genotypic difference in growth inhibition and yield loss of barley under waterlogging stress

Fifteen barley genotypes were exposed to waterlogging stress for 12 d at tillering stage to investigate the genotypic difference in growth inhibition and yield loss.The results showed that leaf chlorosis index(LCI)is not a reasonable indicator for identifying all barley genotypes in their waterlogging tolerance,but it is suitable for most genotypes.Length and width of new leaves initiated after waterlogging reduced for all genotypes except 93-3143,which remained little change under waterlogging condition.In comparison to control,waterlogging caused reduction in plant height and dry weigh by 29.2% and 54.4%,respectively.There was a significant difference in reduction extent among the genotypes,with Franklin being the most reduced.Grain yield was significantly reduced under waterlogging condition,with spike number being most affected among yield components.The reduction in spike number is mainly attributed to few tillers and low effective tillers per plant.The significant differences were detected among the genotypes in their response of yield formation to waterlogging,and local race Yongjiahong Liuleng showed least yield loss,while the two Australian barley varieties had the greatest loss.Path analysis showed that the effect of spike number on yield via grain was quite small,and via grain weight was large and positive;effect of grains per spike on yield via spike number is also small and via grain weight was large and negative;effect of grain weight on yield via both spike number and grains per spike was large,but with different direction.