贵州黔东南州水稻平衡施肥效应

Balanced Fertilization of Rice in Qiandongnan Prefecture of Guizhou Province

为贵州水稻精细化定量施肥和我国农业供给侧结构性改革提供理论依据。采用田间调研和大田试验相结合方法,研究贵州黔东南州水稻产量与肥料施用水平现状及平衡施肥对水稻的增产、养分利用效率、籽粒矿质营养和经济效益的影响。调研结果表明:贵州黔东南州水稻单产水平为7.3t/hm2,收获指数为50.8%;N、P2O5、K2O总养分投入分别为225kg/hm2、128kg/hm2和443kg/hm2,其中化肥N、P2O5、K2O施用量分别为143kg/hm2、94kg/hm2和150kg/hm2。田间试验研究结果表明:与农民习惯施肥水平相比,平衡施肥(农民化肥施用习惯的基础上减氮26.6%、减磷12.2%、减钾10%)可提高水稻产量21.8%,单位面积穗数和穗粒数为提升产量的主效因子;平衡施肥能显著提高籽粒中的锌浓度及单位面积镁、锌积累量,提高水稻产业经济效益。目前黔东南州水稻生产居于全国平均水平,平衡施肥可实现较大增产增收效益和提高籽粒锌、镁矿质营养,施肥策略仍有较大优化空间。

In order to provide the theoretical basis for precision fertilization of rice in Guizhou and supply-side structural reforms of agriculture in China,the current status of rice yield and fertilizer application level in Qiandongnan Prefecture,Guizhou Province and the effects of balanced fertilization on yield increment,nutrient use efficiency,kernel mineral nutrition and economic benefits of rice were studied through a field investigation and a field experiment.Results:The per unit yield and harvest index of rice in Qiandongnan Prefecture was 7.3 t/hm2 and 50.8%respectively.Total nutrient input of N,P2O5 and K2 O was 225 kg/hm2,128 kg/hm2 and 443 kg/hm2 respectively.The application level of N,P2O5 and K2 O was143 kg/hm2,94 kg/hm2 and 150 kg/hm2 separately.In the field experiment,the yield of balanced fertilization pattern(26.6% reduction of N,12.2% reduction of P and 10% reduction of K based on farmers’ conventional application level)increased by 21.8% compared with farmer’conventional application level.Panicles and kernels per panicle in unit area were the main influencing factors for yield enhancement.The balanced fertilization pattern could increase Zn concentration in kernel,and Mg and Zn accumulation per unit area for improving economic benefit of rice industry.The current rice production in Qiandongnan Prefecture was at the mean level in China.The balanced fertilization pattern could realize greater yield and income benefit and improve mineral nutrition of Zn and Mg in kernel.However,the fertilization strategy optimization still had a long way to go.