甘肃彩色棉花抗旱性农艺性状指标的筛选鉴定

Screening of Drought Tolerant Agronomic Trait Indices of Colored Cotton Varieties(Lines)in Gansu Province

以抗旱性不同的白棉、棕棉和绿棉品种(品系)为试验材料,通过水分亏缺控制试验,采用主成分分析和逐步回归分析方法,调查其主要农艺性状指标与抗旱性的关系。结果表明,干旱胁迫下,各彩色棉花的籽棉产量、株高、叶片数、单株成铃数、有效果枝数、果节数、收获指数、茎粗、籽指和上半部分纤维长度均相应的降低;抗旱指数与株高、果节数、单株成铃数、花铃期叶片数、有效果枝数、籽指、单铃重、收获指数、茎粗呈极显著正相关;单株成铃数、单铃重和花铃期叶片数可作为不同色彩棉花简单、直观的抗旱性鉴定指标,有效果枝数、株高、果节数、收获指数和籽指也可作为彩色棉花抗旱评价指标。

Available drought-tolerant indicators that help to screen drought-tolerant parents are significant for breeders to develop new varieties in the water deficient regions. In the paper, the water deficient trials were performed with randomized block design with three treatments. The agronomic traits and drought-tolerant indicators of eight colored cotton varieties （lines） were investi- gated in 2010--2011. The results showed that the seed cotton yield reduced, and plant height, leaf number at flowering-boiling stage, boll number per plant, number of fruiting branch, number of fruit nodes, single boll weight, harvest index, stem diameter, seed index, and fiber length also decreased under drought stresses. There were significantly positive correlation among drought resistance index, plant height, number of fruit nodes, boll number per plant, leaf number at flowering-boiling stage, single boll weight, harvest index, stem diameter, and number of fruiting branch. The principal component and the multiple stepwise regres- sion analyses showed that the boll number per plant, single boll weight, and the leaf number at flowering-boiling stage could be regarded as the simple and intuitive identification indexes of drought resistance in colored cotton, and number of fruiting branch, fiber length, plant height, number of fruit nodes, boll weight, and seed index could be used as indicators for determining or influ- encing colored cotton drought resistance.