缓释氮肥减量配施对不同品种大麦产量的影响

Effects of Reduced Application Rates of Slow-release Nitrogen Fertilizer on the Yields of Three Barley Varieties

以适宜当地生产的扬农啤7号、苏啤11号和苏啤8号3个大麦品种为材料,选用普通尿素和硫包衣尿素(sulfur coated urea,SCU)2种氮肥,设计100%普通尿素、100%SCU全基施、60%SCU基施+40%尿素拔节期追施、60%SCU基施+40%SCU返青期追施、85%SCU全基施、51%SCU基施+34%SCU返青期追施和CK(不施氮肥)7个处理,研究缓释肥减量配施对不同品种大麦产量的影响。结果表明:与常规100%尿素处理相比,100%SCU全基施处理3个品种大麦产量略有降低,60%SCU基施+40%尿素拔节期追施和60%SCU基施+40%SCU返青期追施处理虽然肥料用量未增加,但提高了后期氮肥供应,总体表现为穗粒数和千粒质量增加,尤其前者大麦产量显著提高,以苏啤11号为最大;减肥15%处理降低了总氮量,大麦产量有所降低,以85%SCU全基施处理降低较为显著。从节本和增产综合考虑,生产上推荐苏啤11号品种,并采用60%SCU基施+40%尿素拔节期追施的施肥模式为好。

The objective of this research was to evaluate the effects of reduced application rates of slow-release nitrogen fertilizer on three barley varieties,Yangnongpi No.7,Supi No.8,and Supi No.11,which are suitable for local production.In a field trial,two nitrogen fertilizers-uncoated urea and sulfur-coated urea(hereinafter referred to as SCU)were used to constitute seven treatments for evaluating the effect of reduced application rates of slow-release fertilizer on barley yield.Of the seven treatments,four had the total N application rate of 18.0 kg/667 m2 in the whole growth period,which comprised B1,100%uncoated urea split-applied(50%as a basal treatment;10%,20%,and 20%applied at seedling,rejuvenation,and jointing stages,respectively);B2,100%SCU applied as a basal treatment;B3,60%SCU as a basal treatment+40%urea applied at jointing stage;B4,60%SCU as a basal treatment+40%SCU applied at the rejuvenation stage.Additionally,treatments B5 and B6 both had the reduced total N application rate of 15.3 kg/667 m2 while differing in fertilization mode(B5,85%SCU fully applied as a basal treatment;B6,51%SCU as a basal treatment+34%SCU applied at rejuvenation stage);besides,CK was a control without any nitrogen fertilizers.Compared with the conventional urea treatment B1,the yield of B2 slightly declined for all three barley varieties.B3 and B4 enhanced nitrogen fertilizer supply in the later growth stage compared with B1 and B2,although they had the same total N fertilizer application rate over the whole growth period.Consequently,B3 and B4 showed larger grain number per ear and 1000-grain weight,leading to significantly greater yield,and the yield improvement was higher with B3 than with B4;among the three varieties,Supi No.8 attained the highest yield with B3.By contrast,B5 and B6 showed significant lower yields because they had 15%N reduction in total N supply during the whole growth period compared with B1~B4,with a larger yield reduction occurring with B5.Based on the comprehensive consideration of cost saving and yield increase,the variety Supi No.8 and the fertilization mode 60%SCU base application+40%urea applied as topdressing at the jointing stage are recommended for production.