陆地棉品种田间取样期对纤维品质的影响

通过对陆地棉品种（系）田间不同取样期纤维品质变化的研究表明，纤维长度、纤维整齐度、纤维伸长率、麦克隆值和纤维比强度５项品质性状年度间存在着显著或极显著的正相关关系，亦即各品种（系）的纤维品质在年度间的变化趋势是一致的。６次取样中，各品种（系）的测试结果都有明显的峰值出现，并且各次取样的测试结果与其平均值都有一定的差异。即使同一次取样，各品种（系）的测试结果与其平均值的差异程度亦不同。在优质棉生产中，宜首先选用优质品种，并将其吐絮高峰调整在９月下旬至１０月上旬为宜。在棉花育种的品系预备试验和品系比较试验等试验中，为提高对纤维品质评选的准确性，应综合考虑其它农艺性状或增加取样次数，不宜只依据某一次取样的测试结果来断定某一品系纤维品质的优劣。

Variation of the Fiber Qualities Affected by the Field Sampling Dates in Upland Cotton

The variation of the fiber qualities affected by the field sampling dates in upland cotton was studied in 1990-1991. The result showed that: the positive correlation coefficientes were statistically significant of highly significant between years for the fiber length, the fiber uniformity, the fiber extension rate, the micronaire value and the HVIstrength. The maximum value of each fiber trait as above was obvious in 6 time's samples,and each value of the fiber qualities deviated from its mean for the cultivars. All ofthe deviations were different obviously,even though the samples came from the same timein the field. The cultivar with good fiber qualities would be used firstly, and its boil opening peak time be regulated between semptember 20th and October 10th in cotton production. In order to select fiber qualities correctlly,either sampling times would be increased,or other agronomic characters be thought over, without a line's fiber qualities being judgedonly by one time's sample.