番茄地下滴灌施药对根系分布的调控效应试验研究

通过日光温室内的盆栽试验，研究了地下滴灌施药(氟乐灵)对番茄根系分布的影响及其对滴灌灌水器周围根系的控制效应。试验共设置了2个施药处理和1个不施药的对照。2个施药处理的施药量相同 (均为50ppm的氟乐灵溶液300ml)，施药日期取2个水平：处理1在定植后的第3d施药，处理2在定植后的第24d施药。收获后取根样，用WinRHIZ0软件对各处理的整根特征参数和根密度分布进行分析。结果表明：施药处理1的整根特征参数(包括总根长、总表面、总体积、总根干重)与不施药的对照的各相应参数均无显著差别，而施药处理2的各整根特征参数均明显小于不施药对照。同时，2个施药处理滴头附近的根密度均明显小于不施药的对照，说明施药可以对灌水器周围的根系进行一定的调控，缓解灌水器的根系堵塞问题；2个施药处理的果实中均无农药残留，且各处理与对照的地上部分的生物量无显著差异。

Effect of pesticides application on controlling of tomato root distribution in subsurface drip irrigation

Potted experiments were conducted in a solar-heated greenhouse to investigate the effects of treflan applied into irrigation water on root distribution of subsurface drip irrigated tomatoes and clogging.The experiment includes one controlled sample without treflan and two samples with treatments sharing the same treflan application level but applied at different times.For treatment A the treflan was applied on the 3~(rd) day after transplantation,whereas for treatment B the treflan was applied on the 24~(th) day.The Tomato roots were sampled at harvest and analyzed by using the software WinRHIZO.The results show that,as far as the root length density around the drippers in concerned,both samples with treatment are significantly lower than the sample without treflan,which means application of treflan into irrigation water can reduce the potential of dripper's root clogging.The total root length,surface area,dry weight and volume for sample with treatment A are approximately the same as that without treflan,whereas these parameters of sample with treatment B is significantly lower than the controlled one.There are no differences in tomato biomass accumulation above the ground among these samples.No treflan residues were found in tomato fruits.