Effects of Different Planting Patterns and Nitrogen Fertilizer Ratios on Growth and Yield of Cotton
This research is focused on suitable planting patterns and nitrogen application ratios for cotton,aiming to provide technical support for the high-yield and efficient development of cotton in Xinjiang.Using the cotton variety Xinluzhong 84 as the material,field experiments were conducted in 2022 in Hailou Town,Shayar County,Aksu District,Xinjiang.The experiment employed a split-plot design with planting pattern as the main factor:one film with six rows of wide-narrow spacing[(66+10)cm]with a plant spacing of 12 cm(M6)and one film with three rows of equal spacing(76 cm)with a plant spacing of 6 cm(M3);nitrogen application ratio served as the sub-factor:0∶10(N0),2∶8(N2),4∶6(N4).There were totally six treatments.The total nitrogen application rate for each treatment was 320 kg/ha of pure nitrogen throughout the cotton growth period.Investigations and measurements were conducted on the growth process,agronomic traits,leaf area index(LAI),net photosynthetic rate(Pn),dry matter content,yield,and yield components of cotton.Results indicated that the average lint yield of various nitrogen application ratio treatments under the M3 planting pattern increased by 22.0%compared to the M6 planting pattern,M3N4 and M6N2 treatments exhibited higher lint yields of 3 251.90 kg/ha and 2 895.42 kg/ha,respectively,and Pn of M3N4 treatment increased by 41.2%,12.1%and 34.0%compared to M6N2 treatment,respectively.Under the M3 planting pattern,the average dry matter accumulation during the boll opening stage of each nitrogen application ratio treatment was 35.1%higher than that of the M6 planting pattern.The average number of bolls per plant,individual boll weight,and seed cotton yield were 20.6%,5.3%,and 21.7%higher,respectively,compared to the M6 planting pattern.As the nitrogen application ratio increased,the cotton growth period extended,with the boll opening stage under the M6 planting pattern advancing 5 and 8 days for N0,compared to N2 and N4 treatments,respectively.Under the M3 planting pattern,N0 treatment advanced 4 and 6 days compared to N2 and N4 treatments,respectively.Under the two planting modes,LAI of different nitrogen fertilizer base-topdressing ratio treatment showed N4>N2>N0.In the M6 planting pattern,compared to N0 and N4 treatments,the N2 treatment showed 9.2%and 8.9%increases in Pn during peak flowering stage,aboveground biomass during the boll opening stage,number of bolls per plant,individual boll weight,and seed cotton yield improved by 18.2%and 42.5%,19.8%and 18.3%,9.3%and 5.5%,and 30.3%and 25.4%,respectively.Under the M3 planting pattern,the N4 treatment exhibited 21.1%and 6.7%increases in Pn during peak flowering stage,aboveground biomass during the boll opening stage,number of bolls per plant,and seed cotton yield improved by 32.9%and 24.0%,11.3%and 12.3%,and 12.5%and 11.4%,respectively,compared to N0 and N2 treatments,with no significant difference in individual boll weight.Taking into account the synergistic effect of planting patterns and nitrogen application ratios on cotton yield enhancement,under the conditions of this experiment,the choice of a row spacing pattern of 76 cm with a nitrogen application ratio controlled at 4:6 is most suitable.
CottonPlanting patternNitrogen application ratioGrowth and developmentYield