水肥供应对榆林沙土马铃薯生长和水肥利用效率的影响

摘要

Considering the low water and fertilizer use efficiencies with flood irrigation in sandy soil of Yulin,Northern Shaanxi,the effects of different water and fertilizer supplies on potato growth,yield and water and fertilizer use efficiencies were investigated through the field drip fertigation experiments.There were three water levels:W1 (60％ ETc),W2 (80％ ETc) and W3 (100％ ETc),and three fertilizer levels:F1(1OO-40-150kg/hm2),F2(175-60-225 kg/hm2) and F3(250-80-300 kg/hm2),resulting in a total of nine treatments.Based on those,key indicators (e.g.,growth and yield) of potato in response to different irrigation water and N,P and K amounts were further analyzed.Results showed that different water and fertilizer amounts significantly influenced the plant height,leaf area index,dry weight,yield,water use efficiency (WUE),partial factor productivity of fertilizer (PFP),different tuber quality,yield related relations and economic benefits.The growth,yield and PFP were increased with the increase of irrigation amount,and W3 was more beneficial to growth of potato.However,the water use efficiency of W3 was significantly lower than those of W1 and W2.The average water use efficiency of W1 was 5.83％ and 13.05％ higher than those of W2 and W3.The impact of fertilizer on growth and yield showed an increasing and then decreasing trend,and yield reached the maximum of 59394.98 kg/hm2 at W3F2 level.The water use efficiency of F2 was significantly greater than those of F1 and F3.Linear fitting revealed a positive relationship between plant height,leaf area index,dry weight and yield of potato within a certain range.Comprehensive analysis indicated that the appropriate irrigation and N,P and K amounts can not only maintain the good growth of potato,but also can obtain great yield and economic benefits.From the point of view of obtaining high yield and saving water and fertilizer,W3F2 (100％ ETc,175-60-225 kg/hm2) can be used as an appropriate combination under the present experimental conditions.%通过大田滴灌施肥试验,研究不同水肥供应对滴灌施肥马铃薯生长、产量及水肥利用效率的影响.大田试验设置3个灌水水平W1 (60％ ETc)、W2(80％ ETc)和W3(100％ ETc)以及3个施肥水平(以氮、磷、钾施肥量计)F1(100-40-150 kg/hm2)、F2(175-60-225 kg/hm2)和F3(250-80-300 kg/hm2),共9个处理,分析马铃薯的生长和产量等指标对不同灌水量和不同氮、磷、钾施用量的响应规律.结果表明,灌水量和施肥量均对马铃薯的株高、叶面积指数、干物质量、产量、水分利用效率(WUE)、肥料偏生产力(PFP)、不同块茎质量和经济效益有显著影响.马铃薯生长量、产量和肥料偏生产力均随着灌水量的增加而增加,高水(W3)处理更有利于马铃薯的生长,但W3处理水分利用效率明显低于W1和W2处理,W1处理的平均水分利用效率比W2和W3处理高5.83％和13.05％;生长量和产量随着施肥量的增加先增大后减小,最大产量在高水中肥(W3 F2)处理获得,为59 394.98 kg/hm2,且F2水分利用效率明显大于F1和F3处理.通过线性拟合得出在一定范围内株高、叶面积指数和干物质量对马铃薯产量的增加具有正相关性.综合分析可知,适宜的灌水量和氮、磷、钾施用量不仅能维持马铃薯较好的生长特性,还能获得较大的产量和经济效益.从产量和节水节肥的角度考虑,W3 F2处理(100％ ETc,175-60-225 kg/hm2)可作为基于本试验条件下较适宜的水肥组合.