杂交棉中棉所70后代分离群体产量品质的表型变异分析

中熟转基因抗虫杂交棉中棉所70具有高产优质特点,由高产且综合性状优良的抗虫棉SGK 156与品质优异的渐渗系材料901-001为亲本配制。本文对该杂交种F1及其自交后代F2、F2:3、F2:4和F2:5共4个分离世代材料的皮棉产量和品质性状进行了详细调查和相关性分析。结果表明,杂种F1纤维品质表现突出,上半部平均长度平均为33.00 mm,断裂比强度为33.3 c N·tex-1。在分离群体中,各性状均存在大量的超亲变异,衣分与纤维长度及强度为极显著负相关,与马克隆值为极显著正相关,说明棉花产量与品质间的同步改良仍存在困难。此外,从F2:5株系中挑选出11个优异品系,其中4个材料的皮棉产量超对照,上半部平均长度均高于31.80 mm,断裂比强度在31.0 c N·tex-1以上,铃重均大于6.26 g,衣分最高为38.64%,这表明通过高代自交是可以筛选出具有优异产量及品质性状的品系。本研究为棉花数量性状遗传、基因功能分析、基因聚合育种改良等研究储备了大量的基础材料。

Analysis of Phenotypic Variation in Fiber Yield and Quality in Segregative Populations of Hybrid Cotton CCRI 70

The upland cotton cultivar CCRI 70, a transgenic hybrid with medium maturity and insect resistance, has a superior lint yield, fiber length, and strength characteristics. It was developed by crossing SGK 156, a cotton line with insect resistance, excellent yield, and comprehensive agronomic traits, with 901-001, an introgressive line with high fiber quality. Herein, we analyzed the lint yield and quality characteristics of the hybrid F₁ and its self-pollinated offspring F₂, F_2:3, F_2:4, and F_2:5. The F1 hybrid was shown with outstanding fiber quality, with average fiber length of 33.00 mm and fiber strength of 33.30 cN·tex^－1. The occurrence of fiber attributes exceeding those of the parents was common in the four segregative generations. The lint percentage was significantly negatively correlated with fiber length and strength, but positively correlated with micronaire value, indicating that it is difficult to improve fiber yield and quality simultaneously. Eleven excellent lines were selected from the F_2:5 progeny, of which four exceeded the control cultivar with respect to lint yield.Their average fiber length was ＞31.80 mm, the fiber strength was ＞31.0 cN·tex^－1, the boll weight was ＞6.26 g, and the highest lint percentage was 38.64 %. This shows thatelite lines with a high fiber yield and quality can be screened from higher self-pollination generations of CCRI 70. Moreover,we obtained a large number of basic materials for the analysis of quantitative genetics, gene function, and gene pyramiding breeding programs in cotton.