不同播量对机播免间定苗棉花成铃以及产量和品质的影响

采用常规抗虫棉花品种中571,在郑州市黄河滩区一年一熟、地膜覆盖的栽培条件下,设计小播量(6.75kg·hm~(-2))、中播量(9.00 kg·hm~(-2))、大播量(11.25 kg·hm~(-2))3个免间定苗处理,以常规播量(22.5 kg·hm~(-2))间定苗为对照,研究了不同播量对机播免间定苗棉花成铃及产量和品质的影响。结果表明,大播量免间定苗处理的子棉和皮棉产量最高,子棉产量和皮棉产量分别比对照增加5.10%和4.93%。但3个播量机播免间定苗处理与对照的子棉和皮棉产量差异均不显著,而小播量免间定苗比大播量免间定苗处理的子棉显著减产。免间定苗处理对棉花纤维品质无不良影响。大播量免间定苗处理增产的主要原因是总成铃数显著增加,而铃重和衣分差异不显著。且大播量免间定苗处理成铃时空分布更加合理,有利于集中成铃和早熟。在本试验条件下,加大播量可以弥补免间定苗形成的株距分布不均,中571采用11.25 kg·hm~(-2)的播量免间定苗较为适宜,播量低至6.75 kg·hm~(-2)时造成棉花减产。

Effects of different mechanical seeding rates without seedling thinning process on bolls setting,yield and fiber quality of cotton

To study the effects of different mechanical seeding rates without seedling thinning process on bolls setting,yield and fiber quality of cotton,three treatments,low seeding rate without thinning (6.75 kg · hm-2),medium seeding rate without seedling thinning (9.00 kg · hm-2),and high seeding rate without seedling thinning (11.25 kg · hm-2) were conducted,with the conventional seeding rate with seedling thinning as the control,using normal insect-resistant cotton variety Zhong 571 which was grown under plastic film mulching and single cropping condition in the Yellow River bottomland,Zhengzhou in 2014.The results showed that the seed cotton yield and lint yield of high seeding rate without thinning were the highest.Compared with CK,the yield of the seed cotton and lint yield increased by 5.10％ and 4.93％,respectively.Although there was no obvious difference between the three treatments of seeding rate without seedling thinning and CK on seed cotton yield and lint yield,the lint yield of low seeding rate without seedling thinning reduced significantly compared to high seeding rate without seedling thinning.And the treatment without seedling thinning had no bad effect on quality of cotton fiber.The reason that high seeding rate without seedling thinning increased yield was the total boll productivity increased obviously.High seeding rate without seedling thinning could make more reasonable spatial distribution of cotton bolls,which was beneficial to boll concentration and early maturity.In this study,increasing seeding rate could make up the uneven of spacing distribution caused by without seedling thinning,and the results suggested that high seeding rate without seedling thinning (11.25 kg · hm-2) was suitable for planting Zhong 571,while low seeding rate without seedling thinning (6.75 kg · hm-2) would reduce cotton yield.