播期与密度双因素对陆地棉生长发育及产量的影响OA北大核心CSTPCD

[Objective]To study the effects of different combinations of sowing period and density on the growth of cotton and investigate the suitable planting density for high cotton yield under different sowing peri-ods.[Methods]The experiment was conducted in Shawan City,the Tacheng region of Xinjiang in 2022 by u-sing a split-zone experimental design with three main sowing zones,(April11,April18 and April25,remem-ber B1,B2,B3),and three density sub-zones(180,000,225,000 and 270,000 plants/hm2,renember M1,M2,M3),respectively,to study the effects of the two factors of sowing and density on seedling emergence,fertil-ity process,agronomic traits,dry matter accumulation and yield of cotton.Afterwards,the effects of sowing and density on seedling rate,fertility,agronomic traits,dry matter accumulation and yield were studied.[Results]The results showed that high ground temperature under the film 5 cm after sowing was beneficial to early emer-gence of cotton,and the emergence rate was increased.Under the same sowing period,with the increase of planting density,the fertility period of cotton was prolonged and the mean values of plant height,stem thick-ness,number of fruiting branches and number of boll per plant were significantly reduced.Under the same den-sity,the average fertility period of cotton was shortened with delayed sowing,the average dry matter accumula-tion per plant and population was decreased,the number of boll per plant was significantly lower,and the aver-age seed cotton yield was reduced.Under the early sowing condition,the highest seed cotton yield was 7,519.70 kg/hm2 at high density(M3,270,000 plants/hm2),and the higher yield was 7,671.90 and 6,913.27 kg/hm2 at medium or late sowing conditions at medium density(M2,225,000 plants/hm2),respectively.[Conclusion]On balance,under suitable weather conditions,the appropriate planting density is 270,000 plants/hm2(M3)when the sowing date is April 11,and 225,000 plants/hm2(M2)when the sowing date is A-pril 18(B2)or April 25(B3),which is conducive to the improvement of cotton yield.