水氮管理对设施番茄根系生长的影响

为研究高盐分累积设施土壤（电导率为1 106 μS/cm）中水氮管理对设施番茄根系生长的影响，采用二因素随机区组设计，利用盆栽试验研究了设施土壤中不同水分和氮肥处理对番茄生长和养分吸收的影响.结果表明:与适宜灌溉浇水量为2.1 L/（盆·次）]相比，水分胁迫处理浇水量为1.5 L/（盆·次）]显著抑制番茄根系、株高和生物量的增加，番茄总根长、根总表面积、根尖数分别平均减少16.6%、24.4%、14.3%，养分吸收量平均减少21.7%；高量灌溉浇水量为2.7 L/（盆·次）]可增加番茄果期生物量，增幅达35.5%，但氮素吸收量有所降低.与传统施肥相比，减氮施肥可显著促进番茄植株、根系的生长，从而增加养分吸收量；番茄总根长、根总表面积、根尖数分别增加2.9%~55.3%、10.8%~55.5%、4.9%~62.7%，株高平均增加12.7%，养分吸收量平均增加38.5%，氮肥利用率从9.1%增至30.8%.研究显示，在高盐分累积的设施土壤中，氮肥减施可促进作物根系生长，同时提高氮肥利用率. 

Effects of Irrigation and Nitrogen Managements on Root Growth of Tomato under Greenhouse Condition

A two-factor experiment with randomized block design was conducted to evaluate the effects of irrigation and nitrogen management on root growth of tomato planting in the soil with high salt accumulating facilities (EC values was 1106 μS/cm). The results showed that compared to suitable irrigation (watering amount was 2.1 L/(plot·time)), water stress treatment (watering amount was 1.5 L/(plot·time)) decreased the root length, root surface area and root tip of tomato by 16.6%, 24.4% and 14.3%, respectively, and reduced the total uptake of nutrients by 21.7% on average; the tomato biomass in the sufficient irrigation treatment (watering amount was 2.7 L/(plot·time)) was higher by 35.5% than the suitable irrigation treatment, but N uptake in the sufficient irrigation treatment was lower than in the suitable irrigation treatment. Compared to traditional N management, reduced N management significantly increased the root length, root surface area, and root tip of the tomato by 2.9%-55.3%, 10.8%-55.5%, and 4.9%-62.7% respectively, plant height and total uptake of nutrients in the reduced N managements was higher by 12.7% and 38.5% than traditional N managements, in addition, the N recovery rate was 30.8% in the reduced N management, which was significantly higher than the N recovery rate 9.1% in the traditional N management. In general, reduce N management could promote the growth of crop roots and increase nitrogen use efficiency in the soil with high accumulation of salt under greenhouse conditions.