[Quantitative analysis on the relationships between cotton fiber quality and meteorological factors]

With the method of planting cotton by stages at the sites from Yangtze valley to north Xinjiang, this paper studied the effects of air temperature and sunlight on cotton fiber quality in 2002 approximately 2003. The results showed that with increasing latitude, fiber length increased, while micronaire value and soluble sugar content (SSC) decreased. An ecological model describing the relationships of fiber strength, micronaire value and SSC with air temperature and sunlight was built to determine the optimal range and critical value of air temperature during boll development period. If a high quality fiber (length > or = 27 mm) was targeted, the daily mean temperature (DMT) and minimum temperature (Tmin) during this period should be 21.3 approximately 29.7 and 10.7 approximately 21.3 degrees C, respectively, and the daily temperature difference (DTD) should not be > 15.2 degrees C. Fiber length was the longest when the DMT was 25.4 degrees C. If the lowest fiber length was > or = 25 mm, DMT and Tmin should not be lower than 15.5 and 10.7 degrees C, respectively, and DTD should not be over 17.9 degrees C during boll development period.