不同降水年型地下滴灌追氮对玉米产量的影响

采用完全组合设计,在长期试验基础上探讨了枯、丰2种降水年型滴灌追氮对玉米产量的影响.结果表明:丰水年整体产量高于枯水年,高水高氮和高水低氮处理在丰、枯水年间产量差异不具有统计学意义.枯水年滴灌对产量影响具有统计学意义(P<0.01),水氮互作对产量影响具有统计学意义(P<0.05),追氮对产量影响不具有统计学意义.丰水年滴灌对产量影响具有统计学意义(P<0.05),追氮对产量影响具有统计学意义(P<0.01),水氮互作对产量影响不具有统计学意义.不同降水年型间产量随滴灌量的增大而增大,枯水年滴灌对产量的提高幅度大于丰水年;随追氮量的增加先增大后减小,丰水年增加追氮量对产量的影响均大于枯水年.通过分析,确定了不同降水年型适宜的水肥施用模式:播种期沟施复合肥(N∶P₂O₅∶K₂O=15∶15∶15)450 kg/hm²后,在枯水年滴灌48 mm、追氮120 kg/hm²,丰水年滴灌36 mm、追氮240 kg/hm².

Yield effect of subsurface drip irrigation and nitrogen supplement in different precipitation years

Field experiment was conducted to study the maize yield effect of a long-term subsurface drip irrigation with nitrogen fertilizer supplement in different precipitation years under the condition of nature precipitation. Experiment is designed as a completely random stuff and results indicate that the total yield of wet year is greater than that in drought year. The yields between treatment W3N3 and W3N1 show no significant difference in different precipitation years. Irrigation affects maize yield significantly(P<0.05)in drought year and highly significantly(P<0.01)in wet year. Significant diffe-rence is not found among nitrogen supplement treatment in drought year but is noticed in wet year(P<0.01). There is a significant effect(P<0.05)in the interaction of irrigation and nitrogen supplement in drought year but no significant effect in wet year. Yield increases at first and then decreases with the promotion of nitrogen supplement in both kinds of precipitation years but the increment and decrement of yield in wet year is greater than that in drought year. An appropriate mode of irrigation and fertilization in different precipitation years is established: compound fertilizer(N∶P₂O₅∶K₂O=15∶15∶15)is furrow applied in the amount of 450 kg/hm² as base fertilizer in sowing period; total water supply amount is 48 mm and total nitrogen supplement amount is 120 kg/hm² in drought year; total water supply amount is 36 mm and total nitrogen supplement amount is 240 kg/hm² in wet year.