底部渗灌下薄壳山核桃容器苗的水分利用及生理响应

Water Use and Physiological Characteristics of Carya illinoensis Containerized Seedling under Sub-irrigation

【目的】研究明确底部渗灌对薄壳山核桃水分利用及生长的影响。【方法】以薄壳山核桃一年生容器苗为材料,采用单因素随机区组设计,测定底部渗灌和上方喷灌处理下苗木水分利用效率、光合参数及养分含量。【结果】与上方喷灌相比,底部渗灌能节约灌溉水62%,水分利用效率提高193%;苗木株高、地径分别提高了11.7%和41.5%;净光合速率、气孔导度和蒸腾速率等光合作用指标显著提高;底部渗灌显著地促进了薄壳山核桃容器苗的养分积累,与上方喷灌苗木相比,根系中N增加53.8%、K增加100%,茎干中N增加35.3%、P增加48.3%,叶片中N、P、K分别增加48.7%、117.2%、28.7%。【结论】生产中薄壳山核桃容器苗培育建议采用底部渗灌的方式,节水同时也提高苗木品质。

[ Objective ] The present experiment was conducted to study the effect of sub-irrigation on water use and seedling growth. [ Method ] Water use efficency （WUE）, vegetative growth, photosynthesis and nutrient status of one-year-old pecan containerized seedling were studied under sub-irrigation and overhead irrigation. [ Result] Sub-irrigation might conserve at least 62 % of irrigation water, improve water use effi- cency （WUE） by 193 % compared with overhead irrigation. Seedling height and root collar diameter（RCD） were increased by 11.7 % and 41.5 %. Net photosynthetic rate, stomata conductance, transpiration rate were also improved significantly. N and K content of root in- creased by 53.8 % and 100 % , N and P content of stem increased 35.3 % and 48.3 % , N, P and K content of leaf increased by 48.7 % , 117.2 % and 28.7 % respectively. [ Conclusion ] Sub-irrigation should be suggested applying in pecan containerized seedling cultivation be- cause of its water conservation characteristic and good seedling quality.