Qian Xue-ya, Jing Rui-lian, Wang Hui, Chang Xiao-ping
College of Agronomy, Northwest A & F University, Yangling 712100, Shaanxi China.
Ying Yong Sheng Tai Xue Bao. 2009 Dec;20(12):2957-63.
Taking one hundred and fifty doubled haploid (DH) lines of winter wheat cultivars Hanxuan 10 x Lumai 14 as well as their parents as test materials, the genetic bases of top three leaves length, breadth, and angle at mid-filling stage, and their correlations with yield traits were studied under two water regimes rainfed (drought stress, DS) and well-irrigation (WI) in 2005-2007. Under DS, the leaf length and width of DH lines and their parents were significantly lower than those under WI, whereas the leaf angle had a miscellaneous variation. Under the two water regimes, all the test traits of DH lines had a transgressive segregation, with the variation coefficients ranged from 5.1% to 45.9%. The heritability and gene numbers for the given traits showed great differences. Under WI and DS, the heritability of flag leaf angle (FLA) was the highest (91% and 97%, respectively), and that of the third leaf angle (TLA) was the lowest (23% and 31%, respectively). However, the gene number for FLA (4 and 2 under WI and DS, respectively) was the least, and that of TLA (21 and 25, respectively) in 2007 was the most. Interactive effects were observed among the genes controlling FLA, second leaf angle (SLA), and TLA under WI and DS, and controlling third leaf length (TLL) under WI. The grain number per spike and the grain weight per spike were positively correlated with the length and width of top three leaves, and the thousand-grain weight and the yield per plant were significantly correlated with TLL, FLA, and SLA, but all correlation coefficients were smaller ( < 0.481). It was suggested that the selection of top three leaves length and width should be carried out in the early generations of breeding procedure, while that of leaf angles should be carried out in advanced generations. An appropriate soil moisture regime retained in the critical growth period of the leaves would promote their growth and contribute to the grain yield.
以冬小麦品种邯6172×鲁麦14的150个加倍单倍体（DH）系及其亲本为试验材料，于2005—2007年在雨养（干旱胁迫，DS）和充分灌溉（WI）两种水分条件下，研究了灌浆中期顶部3片叶的长、宽、角度的遗传基础及其与产量性状的相关性。在干旱胁迫条件下，DH系及其亲本的叶片长度和宽度显著低于充分灌溉条件下，而叶角则表现出复杂的变化。在两种水分条件下，DH系所有测试性状均存在超亲分离，变异系数在5.1%~45.9%之间。各性状的遗传力和基因数目差异较大。充分灌溉和干旱胁迫条件下，旗叶叶角（FLA）的遗传力最高（分别为91%和97%），倒三叶叶角（TLA）的遗传力最低（分别为23%和31%）。然而，旗叶叶角的基因数目最少（充分灌溉和干旱胁迫条件下分别为4个和2个），2007年倒三叶叶角的基因数目最多（分别为21个和25个）。充分灌溉和干旱胁迫条件下，控制旗叶叶角、倒二叶叶角和倒三叶叶角的基因之间以及充分灌溉条件下控制倒三叶叶长的基因之间存在互作效应。每穗粒数和每穗粒重与顶部3片叶的长度和宽度呈正相关，千粒重和单株产量与倒三叶叶长、旗叶叶角和倒二叶叶角显著相关，但所有相关系数均较小（<0.481）。建议在育种早代选择顶部3片叶的长度和宽度，而在高代选择叶角。在叶片关键生育期保持适宜的土壤水分状况将促进叶片生长并有助于提高籽粒产量。
