摘要
【目的】研究黄河流域低肥力棉田施氮量对棉花产量、养分吸收利用率、土壤速效氮及脲酶活性的影响。【方法】以中棉所79为材料,设置6个施氮量处理(0、90、180、270、360、450 kg·hm^(-2),分别以N0、N90、N180、N270、N360、N450表示),于2016和2017年进行连续两年大田试验。测定棉花产量、干物质质量、氮磷钾积累量、氮肥利用率、0―100 cm土层铵态氮及硝态氮含量、0―100 cm土层脲酶活性等指标。【结果】(1)与N0相比,除2016年N90处理外,其余施氮处理均显著提高籽棉产量。两年N360处理显著提高了棉花单株成铃数,籽棉产量与其它施氮处理间无显著差异。施氮对棉花衣分无显著影响。(2)与N0相比,施氮显著提高棉花干物质积累量。施氮90～360 kg·hm^(-2),棉花氮、磷、钾积累量随施氮量的增加而增加,N450处理氮、磷、钾积累量较N360处理下降。随着施氮量增加,棉花氮农学利用率、氮肥偏生产力降低;当施氮量超过360 kg·hm^(-2),氮生理利用率开始降低,但各处理间差异不显著。(3)除N90处理外,其余各处理41―80 cm土层NO3--N含量较N0显著提高;N270、N360、N450处理41―80 cm土层NO_3^--N含量显著高于N0、N90和N180处理;施氮对土壤NH_4^+-N含量无显著影响。(4)施氮0～360 kg·hm^(-2),土壤脲酶活性随施氮量增加而增强;超过360 kg·hm^(-2),土壤脲酶活性下降。【结论】氮肥经济最佳施氮量为277.0 kg·hm^(-2)。当施氮量超过360 kg·hm^(-2)时,棉花养分积累量降低,土壤NO3--N含量升高,土壤脲酶活性受到抑制,氮肥利用率降低,棉花增产效果不明显。
[Objective] The effects of nitrogen(N) application rates on cotton yield, nutrient uptake and utilization rate,soil available N and urease activity were investigated in low-fertility cotton fields of the Yellow River Basin.[ Methods]Six N application rate treatments, 0, 90, 180, 270, 360 and 450 kg·hm^-2(N0, N90, N180, N270, N360 and N450, respectively),were established using cotton CCRI 79 in the field during 2016 and 2017. The cotton yield, dry matter quality, N, phosphorus and potassium accumulation levels, N use efficiency, 0 – 100-cm soil layer ammonium and nitrate N contents, 0 – 100-cm soil layer urease activity and other indicators were investigated.[Results](1) Compared with N0, the N treatments significantly increased seed cotton yield, except the N90 treatment in 2016. Two years of N360 treatments significantly increased the number of bolls per cotton plant, while no significant differences were found among the seed cotton yields with other N treatments. The N application rates had no significant effect on lint percentage.(2) Compared with N0, N applications significantly increased the cotton dry matter accumulation. The accumulation of N, phosphorus and potassium in cotton increased along with the Napplication rates in the 90 – 360 kg·hm^-2 range. The levels of N, phosphorus and potassium in N450-treated cotton decreased compared with N360-treated cotton. As the N application rates increased, the N agronomic efficiency and N fertilizer partial productivity of cotton decreased. When the N application rates exceeded 360 kg·hm^-2, the N physiological efficiency began to decrease, but there were no significant differences among treatments.(3) The nitrate N contents in the 41 –80-cm soil layers of the treatments, except for N90, significantly increased compared with N0. The nitrate N contents in the 41 –80-cm soil layers of N270-, N360-and N450-treated cotton were significantly increased compared with those of N0, N90 and N180. However, N applications had no significant effects on the ammonium N contents in the soil.(4) The soil urease activities increased when N application rates were less than 360 kg·hm^-2, and then decreased when the N application rates were greater than 360 kg·hm^-2.[Conclusion] The optimum N application rate was 277.0 kg·hm^-2. When the N application rates were greater than 360 kg·hm^-2, the nitrate N contents in the soil increased. However, the nutrient accumulation levels and the N fertilization efficiencies decreased, and the soil urease activities were inhibited. No obvious increase in cotton yield was observed.
作者
秦宇坤
李鹏程
郑苍松
孙淼
刘帅
董合林
徐文修
Qin Yukun;Li Pengcheng;Zheng Cangsong;Sun Miao;Liu Shuai;Dong Helin;Xu Wenxiu(Xinjiang Agricultural University Agricultural College, Urumqi 830052, China;Institute of Cotton Research, Chinese Academy of Agricultural Sciences/State Key Laboratory of Cotton Biology, Anyang, Henan 455000, China)
出处
《棉花学报》
CSCD
北大核心
2019年第3期242-253,共12页
Cotton Science
基金
国家重点研发计划"肥料氮素迁移转化过程与损失阻控机制"(2017YFD0200107)
国家现代农业产业技术体系棉花产业体系建设专项资金(CARS-18-17)
关键词
施氮量
产量
氮肥利用率
土壤速效氮
脲酶活性
nitrogen application rate
yield
nitrogen fertilization efficiency
soil available nitrogen
urease activity
