Ecological effect and the utilization rate of K nutrient for different K use efficiency cotton genotypes

Potassium plays a vital role in plant physiological and biochemical processes. It is important in cotton growth as it influences cell division and processes and products related to photosynthesis. Since K fertilizer resources are limited and there is great demand for K fertilizer in China’s agricultural production, higher K use efficiency and the development of high K use efficient crop cultivars has become increasingly important. The Huazhong Agricultural University established a field study at Honghu County of Hubei Province in 2010 to study the mechanisms of high K use efficiency with different cotton genotypes since 2010.

Results have showed that during the period between vegetative and reproductive growth, genotypes with high K use efficiency (HEG) are slower than with less efficient genotypes (LEG). Thus HEG cotton went into reproductive growth earlier than LEG. Under K deficient conditions, HEG cotton prioritizes its K supply to the top-most functional leaves, while when K supply is relatively abundant, K content increases rapidly with the lower leaves. In LEG cotton under both low and high K supply conditions, K concentrations in upper leaves was always higher than that of lower leaves. In many cotton plant organs, K content in HEG cotton was less than that of LEG. At harvest time, HEG cotton could use relatively lower K content to meet its normal growth and development needs. Through the analysis of yields, economic benefit, and nutrient use, it is apparent that HEG cotton has consistent advantages over. Hubei-37