低酚棉品种资源遗传变异的研究

Study on Genetic Variability of Germplasm Resources of Low Gossypol Cotton

本文对34个国内外不同来源的低酚棉品种资源的单株子棉产量、单株皮棉产量、果枝数、单株结铃数、铃重、衣分、衣指、子指8个产量性状和纤维长度、整齐度、比强度、伸长率、麦克隆值5个纤维品质性状的遗传变异进行了研究。结果表明,这13个数量性状大都受环境因素影响较大,遗传变异潜力小到中等。相比而言,单株子棉产量、单株皮棉产量、单株铃数、单铃重4个性状的遗传变异潜力较大,遗传变异系数在10％以上;纤维整齐度、长度、比强度、仲长率和衣分5个性状遗传变异潜力较小,遗传变异系数在5％以下;其它性状遗传变异潜力介中,遗传变异系数为5％～10％。遗传力分析表明,铃重、子指、衣指、衣分的广义遗传力较高,均在70％以上,而纤维比强度、整齐度、伸长率的遗传力较低,均在60％以下,其它性状的遗传力在60％～70％之间。在此基础上,研究了这13个数量性状的遗传进度,表明在产量及其组分(单株结铃数、铃重)上选择效果较好,而5个纤维品质指标的选择效果较差。

The genetic variability of 13 yield and fiber characters was studied with 34 glandless cotton germplasm resources from various regions. The results showed that the majority of these 13 characters was easily affected by environmental factors and their potentiality of genetic variability was small to medium.The genetic coefficient of variance (GCV) of seed cotton yield per plant, lint yield per plant, boll number per plant and single boll weight was more than 10%; the GCV of fiber uniformity, span length, fiber strength, fiber elongation and lint percentage was less than 5%; and the GCV of 5-10% was found in the number of fruit branches per plant, lint index, seed index and micronaire value. The broad heritability (H_B) of boll weight, seed index, lint index and lint percentage was more than 70%; the H_B of fiber strength, uniformity and elongation was less than 60%; and the H_B of other characters was between 60% and 70%. The genetic gain calculation indicated that a better selection effect was found in yield and its components (the number of bolls per plant, boll weight).