短季棉品种早熟性构成因素的遗传分析

对5个推广短季棉品种的9个生育性状进行了遗传分析，结果表明：苗期、蕾期、铃期、第一果枝节位和株高与全生育期呈显著正相关，与霜前花率呈显著负相关，与环境相关则较小，说明它们之间的关系主要受遗传控制。苗期、蕾期、铃期天数多、果枝节位高和植株高大的品种，其全生育期长，霜前花率低，表现晚熟。反之，全生育期短，霜前花率高，早熟性好。9个生育性状的早熟性遗传分析的结果:脱落率和蕾期遗传力低，苗期、铃期、全生育期、霜前花率、果枝节位、铃重的遗传力较高，而且能够稳定遗传。经预期遗传进度估算，目前推广的短季棉品种早熟性潜力：霜前花率可提高24%左右，达到90%以上；全生育期可缩短9-10天；果枝始生节位可降低1-2节。结果还表明短季棉品种铃重与霜前花率为遗传正相关，为棉花遗传学提供了新的重要补充内容。

INHERITANCE ANALYSIS ON EARLINESS COMPONENTS OF SHORT SEASON COTTON VARIETIES IN G. HIRSUTUM

Nine growth characters of 5 extended cotton varieties were studied for inheritance analysis in short season upland cotton. It shows that the periods of seedling, squaring and bolling are significantly positive related to the first setting sympodiumand plant height as well as the period of whole growing, and highly negative correlation with the percentage of pro-frost lint. Those Characters are less correlation with the environment. In accordance with the results it is suggested that the relation among these components is controlled by gene actions. The more days at the periods of seedling, squaring and boiling, the higher the plant height and node of the first fruit branch, the longer the whole growing period, the lower the rate of pre-frost lint and the later the maturity. Otherwise, the shorter period of the whole growith express the higher rate of pre-frost lint yield and better earliness.The results of genetic analysis to 9 growth characters show that the rate of abscission and the hereditary capacity at squaring period are low, the other characters are highly heredity ability and stable inheritance. The expected genetic advance evaluation to these characters shows that the rate of pre-frost lint may incease about 23% and up to above 90%. The whole growing period will shorten 7-9 days, the first node of fruit branch shorten 1-2 nodes.The results present that boll weight and the rate of pre-frost lint have positive relations in short season cotton, which is an important complemental content to be supplied for cotton genetics.