有机无机肥配施对水稻产量、氮吸收利用和根系形态的影响

Effects of Combined Application of Organic and Inorganic Fertilizers on Rice Yield,Nitrogen Uptake and Utilization and Root Morphology

为解决化肥过量施用造成的资源浪费、环境污染和影响农业可持续发展的问题。本研究采用大田试验,设置PK(只施磷钾肥,对照)、NPK(常规施肥)、1/2NPKM(化肥减施50%配施有机肥)和M(单施有机肥)共4个处理,研究有机无机肥配施对水稻产量、氮肥利用率和根系形态的影响。结果表明:NPK处理和1/2NPKM处理比PK处理分别显著增产29.53%和27.58%,比M处理分别显著增产22.11%和20.28%;与PK处理相比,NPK处理水稻株高和穗长显著增加13.85%和8.17%,NPK处理和1/2NPKM处理有效穗数显著增加37.19%和26.18%,千粒重以M处理最高。各处理水稻干物质积累量和氮积累量均随生育期进行而增加,与M处理相比,1/2NPKM处理分蘖期、抽穗期和成熟期水稻干物质积累量依次显著增加36.34%、31.85%和22.50%,氮积累量依次显著增加68.24%、73.82%和46.67%,1/2NPKM处理分蘖期、抽穗期和成熟期氮肥利用率是M处理的6.74、5.01、8.61倍。不同施肥处理对水稻根系形态有显著影响,其中分蘖期1/2NPKM处理根长、根表面积和根体积较M处理依次显著增加62.79%、51.92%、57.28%,抽穗期根体积显著增加18.52%,成熟期根长和根表面积显著下降29.93%和18.70%。综上,化肥减施50%配施有机肥处理较单施氮磷钾处理虽然保证水稻产量,但降低了氮肥利用率和水稻根系生长。本研究结果对贵州黄壤稻田化肥合理减施配施有机肥具有指导意义。

To solve the problems of resource waste and environmental pollution caused by excessive application of chemical fertilizers,and promote the sustainable agricultural development,a field experiment was conducted.Four treatments were set as PK(P and K fertilizers only,control),NPK(conventional fertilization),1/2NPKM(50%fertilizer reduction combined with organic fertilizer application)and M(organic fertilizer alone),to study the effects of combined application of organic and inorganic fertilizers on rice yield,nitrogen use efficiency and rice root morphology.The results showed that the yield of treatment NPK and 1/2NPKM were significantly increased by 29.53%and 27.58%compared with that of treatment PK,and by 22.11%and 20.28%compared with that of treatment M,respectively.Compared with treatment PK,treatment NPK significantly increased plant height and panicle length by 13.85%and 8.17%respectively,treatment NPK and treatment 1/2NPKM significantly increased the effective panicle number by 37.19%and 26.18%respectively,and treatment M had the highest 1000-grain weight.The accumulation of dry matter and nitrogen in each treatment increased with the growth period.Compared with the treatment M,treatment 1/2NPKM significantly increased the dry matter accumulation of rice at tillering stage,heading stage and maturity stage by 36.34%,31.85%and 22.50%respectively,and increased the nitrogen accumulation of rice by 68.24%,73.82%and 46.67%respectively.The N utilization rate of treatment 1/2NPKM was 6.74,5.01 and 8.61 times that of treatment M at tillering stage,heading stage and maturity stage.Different fertilization treatments had significant impact on rice morphology.Compared with treatment M,treatment 1/2NPKM significantly increased the root length,root surface area and root volume of at tillering stage by 62.79%,51.92%and 57.28%,respectively,increased the root volume at heading stage by 18.52%,and significantly decreased the root length and root surface area at maturity stage by 29.93%and 18.70%,respectively.In conclusion,compared with treatment NPK,50%reduction of chemical fertilizer combined with organic fertilizer ensured rice yield,but reduced nitrogen use efficiency and root growth.The results of this study have certain guiding significance for rational chemical fertilizer reduction and organic fertilizer application in yellow soil paddy fields of Guizhou Province.