Trends and temporal-spatial distribution of fiber quality in the national cotton variety regional trials.

Abstract

This study applied a grey predicting model to predict the trend of cotton fiber quality for next 5 and 10 years in the Yellow River Valley (YeRV), the Yangtze River Valley (YaRV) and the Northwest Inland Region (NWIR) based on the data set from the fiber quality traits of candidate cultivars in National Cotton Variety Regional Trials during 2005-2014. The temporal and spatial distributions of cotton trails in the three major cotton producing regions were analyzed. The results showed that the overall fiber quality of the Regional Cotton Variety Trials was improved during 2005-2014. Fiber length showed excellence and the distribution of threshold increased to 27.0-32.0 mm, and the fiber length of most cultivars reached 29 or 30 mm. Fiber strength also showed an increase trend. The proportion of high level (31.0 cN·tex-1) cultivars in YaRV was as high as 61.1% in 2011. Micronaire was significantly different among the three major cotton producing regions. In YeRV, micronaire was increased from class B2(4.3-4.9) to class C2(≥5.0). In YaRV, it maintained in a high level of class C2; while it performed excellent in class A (3.7-4.2) and B2 (4.3-4.9) in NWIR. As a comprehensive fiber quality trait, spinning consistency index decreased from NWIR, YaRV to YeRV, and was ranged from 130 to 149, which was suitable for 40-50 spun yarn and accounted for about 80.0% over the total. We concluded that NWIR had the best fiber quality, followed by YaRV and YeRV in recent ten years. In the near future, fiber quality in the regional cotton variety trails would slightly increase in YaRV, but significantly decrease in YeRV and NWIR. These changes should be highly concerned for breeders, the committee of National Cotton Variety Regional Trials and approval of management department in China.