title: [Effects of nitrogen fertilization rate and planting density on cotton biomass and nitrogen accumulation in extremely early mature cotton region of Northeast China].
abstract: Taking two cotton cultivars Liaomian 19 and NuCOTN 33B with different growth periods as test materials, a field experiment was conducted to study the effects of different nitrogen fertilization rates (0, 240 and 480 kg N x hm(-2)) and different planting densities (75000, 97500 and 120000 plants x hm(-2)) on the cotton biomass, nitrogen accumulation, and accumulative nitrogen utilization in the planting region of extremely early mature cotton in Northeast China. The dynamics of cotton biomass and nitrogen accumulation of the two cultivars with their growth process followed Logistic model. Both nitrogen fertilization rate and planting density had significant effects on the cotton nitrogen accumulation dynamics and the cotton yield and quality. In all treatments, the beginning time of rapid accumulation of nitrogen was about 13 d earlier than that of biomass. In treatment plant density 97500 plants x hm(-2) and nitrogen fertilization rate 240 kg x hm(-2), the eigenvalues of the dynamic accumulation models of nitrogen and biomass for the two cultivars were most harmonious, lint yield was the highest, fiber quality was the best, and accumulative nitrogen utilization efficiency was the highest. In the study region, the earlier beginning time of rapid accumulation of nitrogen and biomass and their higher accumulation rates were benefit to the formation of higher cotton yield.
authors.affiliation: Key Laboratory of Crop Growth Regulation, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China. wangzisheng6666@126.com
authors.forename: Zi-Sheng
authors.initials: ZS
authors.lastname: Wang
authors.forename: Min
authors.initials: M
authors.lastname: Xu
authors.forename: Guo-Wei
authors.initials: GW
authors.lastname: Zhang
authors.forename: Lu-Lu
authors.initials: LL
authors.lastname: Jin
authors.forename: Ying
authors.initials: Y
authors.lastname: Shan
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Wu
authors.forename: Zhi-Guo
authors.initials: ZG
authors.lastname: Zhou
mesh_terms: D000383:Agriculture / Q000379:methods; D018533:Biomass; D002681:China; D005308:Fertilizers; D003368:Gossypium / Q000254:growth & development* / Q000378:metabolism*; D016015:Logistic Models; D009584:Nitrogen / Q000378:metabolism*
chemical_list: D005308:Fertilizers; D009584:Nitrogen