光子陆地棉种质资源主要性状的遗传评价

以102份光子陆地棉材料为母本，分别与遗传标准系TM-1杂交，获得102个F₁群体。采用随机区组设计，设置3个重复，对光子陆地棉材料主要性状进行遗传评价。结果表明，调查的11个性状表型差异均较大，材料间产量性状(株高、果枝数、铃数、铃重、衣分和子指)差异大于纤维品质性状(纤维长度、纤维强度、马克隆值、整齐度和伸长率)，特别是衣分、铃数等性状差异更明显; 除果枝数、马克隆值、伸长率以外，光子亲本群体其他性状的平均值都小于F₁群体。而亲本群体所有性状的变异系数均大于F₁，不同光子材料的杂种优势有很大差别，中亲优势和超亲优势也有很大的差别，有些种质某些性状的中亲、超亲优势为负值，其后代性状表现劣势; 纤维品质性状的中亲、超亲优势与毛子程度均呈负相关，而产量性状的中亲、超亲优势与毛子程度均呈正相关，说明可利用光子材料杂种优势改良纤维品质，而其后代产量性状的杂种优势利用受到限制; SSR分子标记遗传相似系数与各个性状的中亲、超亲优势的相关都不显著，说明在光子材料的育种中，杂种优势是不能通过亲本之间的遗传背景相似程度来预测的。

Genetic Evaluation of Major Traits in Fuzzless Upland Cotton Germplasm

A total of 102 fuzzless seed upland cotton varieties (G. hirsutum) as female parents were crossed with genetic standard line TM-1 (as male parent) to analyze the main traits in the F₁ population with random blocks design with three replications. The results showed that there were significant differences among eleven agronomic traits between different parents, and the difference of yield traits (plant height, fruit branch number, boll number, boll weight, lint percentage, and seed index) was higher than that of fiber quality traits (length, strength, micronaire, uniformity, elongation rate), especially for lint percentage, boll number, except for fruit branch number, micronaire and elongation rate, the mean values of other traits in parent populations were lower than those in F₁ populations, however, the coefficient of variation in fuzzless seed parents was higher than that of F_1. The heterosis including mid-parent heterosis and heterobeltiosis highly varied in different varieties. Some traits of some varieties with negative heterosis showed inferior descendants, The mid-parent heterosis and heterobeltiosis in fiber quality traits showed negative correlation with fuzzless rate, but yield traits showed positive correlation with fuzzless rate, indicating that the heterosis could be applied for fiber quality improvement but might be limited for the yield improvement, No significant correlation was found between genetic similarity coefficients based on SSR markers and heteroses in all traits, indicating that it is difficult to predict heterosis by using genetic background similarity of parents in fuzzless cotton breeding.