灌溉定额对小麦产量、追肥肥效及损失的影响

EFFECT OF IRRIGATING QUOTA ON WTEAT YIELD, TOPDRESSING EFFICIENCY AND ITS LOSS

在壤质潮土上,采用田间小区试验和^(15)N尿素微区试验,研究了不同灌溉定额对小麦产量、追肥肥效、利用率及损失率的影响。结果表明,在不追肥情况下,大水漫灌比适量水灌溉增产作用并不显著。追施尿素后进行大水漫灌,产量反而比适量水灌溉处理有所降低,大水漫灌明显地降低了追肥肥效。每次亩浇水70m^3,追肥利用率最高,损失率最低。浇水40m^3和100m^3处理,追肥利用率分别比浇水70m^3处理降低4.74％和0.64％,损失率分别增加4.63％和5.54％。

Field experiment and 15N-labelled urea microplot experiment on loam soil show that the yield increased by superhigh quota irrigation treatment is not significant as compared with normal quota irrigation treatment with no topdressing.However,after topdressing urea,the wheat yield of super-high quota irrigation treatment is even less than that of normal quota irrigation treatment.The superhigh quota irrigation decreases the efficiency of topdressing urea obviously.Under the irrigating quota of 70m3/mu,the efficiency of topdressing urea is the highest and the loss rate is the lowest.The efficiencies of topdressing urea at the irrigating quota of 40m3/ mu and.100m3/mu have decreased by 4.74% and 0.64% respectively;while the loss rates have increased by 4.63% and 5.54%.