Differences in Growth and Potassium-Use Efficiency of Two Cotton Genotypes

Abstract

To study the differences in growth and potassium (K)-use efficiency of two different K-use-efficiency cotton genotypes, a pot experiment was conducted in 2007. Experimental materials include two cotton genotypes (HG103 and LG122) and two K application levels (0 and 0.23 g kg -1 soil). The initial dates of various growth stages, plant heights, numbers of leaves, squares, and bolls, and the amount of litter during the whole growing season were recorded. The distribution and accumulation of dry matter and K content in various organs were measured to compare the differences in K-use efficiency. Significant differences (P < 0.05) between the two genotypes and K levels were found in initial bolling time. At the reproductive growth stage, the plant heights and leaf number of HG103 were less than those of LG122. Greater numbers of squares and bolls were recorded from HG103 than LG122 with K application. Significant differences (P < 0.05) existed in dry matter and K contents in each organ in the two genotypes and K-application levels. The seed cotton yields of HG103 were 3.24 times larger than those of LG122 with K application and 1.77 times larger than those of LG122 with the marginal K treatments. Reproductive-to-vegetative ratios (RVR) and harvest indices (HI) of LG122 were less than those of HG103 whether K was applied or not. The ratios of K in reproductive organs to vegetative organs for LG122 were 0.47 and 0.51 with K application and the marginal treatments, respectively, and for HG103 were 0.66 and 0.75 respectively. The K accumulations in root, stem, and litter of LG122 were more than those of HG103, whereas those in leaves and bolls were less than those of HG103. These results indicated that HG103 transferred more photosynthesis products and K to cotton reproductive organs than LG122.

Genotypic variation of potassium uptake and use efficiency in cotton (Gossypium hirsutum)

“…2). This was consistent with previous studies (Xia et al, 2011). However, no significant difference was observed in plant K accumulation between the two genotypes regardless of K supply, indicating that there was no pronounced difference in K uptake between the two genotypes.…”

“…As the crop develops, both the rate of fruit production and the rate of fruit retention decline (Bange and Milroy, 2004). The results of our earlier study show that the boll stage of genotype H103 started 9-36 d earlier than that of genotype L122 (Xia et al, 2011). In our study, the higher LI and LKPI values of genotype L122 were to some extent attributed to late maturation, which implied clearly a waste of resources (both biomass and K) and low K-use efficiency, as illustrated in Fig.…”

Two typical K-efficiency cotton genotypes differ in potassium absorption kinetic parameters and patterns

“…In this study, two genotypes of cotton (Gossypium hirsutum L.) differing markedly in K efficiency (K-efficient genotype 103 and K-inefficient genotype 122) were selected from 86 cotton genotypes (Jiang et al 2005). These two genotypes have been used in multiple studies since 2001, and found the dramatic difference of K + absorption by morphologically diverse root systems (Hao et al 2011) and physiological indicators related to K uptake efficiency Xia et al 2011). However, the mechanism responsible for K absorption differences remains unclear especially interfered with TEA and NEM.…”

Effect of Water Stress and Fertilization on Cotton Productivity Under Calcareous Soil Conditions

“…Cotton growth, yield and maturity are greatly influenced by NPK fertilizers application which increases yield and yield components and fiber quality (Xia et al, 2013;Adnan et al, 2017;Wajid et al, 2017). Also, Policepatil et al (2009) revealed that increased NPK fertilization to cotton may result in more accumulation of photosynthetic assimilates that resulted in higher fruit weight.…”