Effect of sowing dates on cotton yield, fiber quality, and uptake and utilization of nutrients in Inner Mongolia west desert area, China

Abstract

Field experiments were conducted in 2014 and 2015 at the "Inner Mongolia cotton comprehensive test station" (39°27' N, 105°39' E) in Alxa Left Banner of Alxa League in Inner Mongolia. By using cotton cultivar CCRI-50 as material and the "6 cotton rows with 3 dripping pipes under a plastic film mulching" plantation pattern, different sowing dates (20-Apr, 30-Apr and 10-May) were set to study the effect of sowing dates on cotton yield, fiber quality and nutrient uptake and utilization. The results showed that as the sowing date delayed, the development of cotton plant was delayed, the yield forming stage shortened, and the mean daily temperature of boll deve-lopment reduced, but the harvesting density increased. Sowing date influenced the biomass accumulation, fiber yield and fiber quality, it also influenced the absorption and distribution of N, P and K. Among the three sowing dates, the biomass distribution proportion to reproductive organ, nutrition (N, P and K) accumulation, lint production efficiency of nutrient and yield were higher in the cotton plant that was sowing at 30-Apr, the seed cotton and lint yield were the highest which could reach up to 6505.9 kg·hm-2 and 2660.9 kg·hm-2, respectively, and the fiber quality was better than that of 10-Mar. For the plant which was sowed at 20-Apr, harvesting density, biomass and nutrient accumulation were the lowest, although economic coefficients of biomass and nutrient were the highest, and the seed cotton and lint yield were respectively 10.9%-14.0% and 11.1%-14.2% lower than that of 30-Apr. When sowing at 10-May, cotton could avoid the low temperature during seed germination, but mean daily temperature during boll development were the lowest, although biomass and nutrient accumulation were the highest. The economic index, lint production efficiency of nutrient were the lowest, which leading to the poorest fiber quality, lowest seed cotton and lowest lint yield which were respectively 32.5%-34.7% and 35.9%-36.2% lower than that of 30-Apr. These results suggested that the optimum sowing date for cotton planting was about 30-Apr in Inner Mongolia west desert area.