施肥对蕹菜生长及品质的影响

在褐土上采用盆栽试验研究了鸡粪、包衣尿素、素、硝铵4种肥料对蕹菜硝酸盐累积以及其他品质指标的影响，结果表明，在低量施氮下，鸡粪处理表现缺氮症状，长势不及等氮量的尿素处理，在中量施氮情况下，蕹菜长势为：鸡粪，包衣尿素＞硝铵＞尿素。在硝酸盐指标上，施用等量鸡粪可以明显降低其含量；在中量施氮情况下，植株的硝酸盐含量为：尿素＞硝铵、包衣尿素＞鸡粪；随着施氮量的增加，植株硝酸盐呈增加趋势，以尿素处理增加更为明显。鸡粪的施用量增加有利于提高蕹菜的Vc有可溶糖含量，但尿素素处理没有表现出类似的结果：在中量氮素投入情况下，硝铵及包衣尿素处理的Vc含量相对较高、中、高量化学氮肥施用显著地促进了土壤无机氮累积，其中又以尿不处理累积为甚，包衣尿素累积量较少，因此在生产中鸡粪或化学氮施肥用量的合理控制是蔬菜施肥中一项非常重要的工作。

Effects of Various Fertilizers on Growth and Quality of Water Spinach

Four fertilizers chicken manure,urea,resin coating urea and ammonium nitrate were chosen to study the effect of each fertilizer on water spinach growth and quality.Chicken manure and urea were applied in 3 N levels,0 06 g/kg,0 18 g/kg and 0 36 g/kg,while other 2 fertilizers were applied in 0 18 g/kg only.The results indicated that the biomass of water spinach treated with 0 06 g/kg N of chicken manure was lower than that with urea,while under 0 18 g/kg N,the biomass decreased in order of chicken manure,resin coating urea>ammonia nitrate>urea.With the increase of N rate,plant nitrate content accumulated greatly,especially for urea treatment.With the same N rate,plant nitrate content decreased with urea>ammonium nitrate,resin coating urea>chicken manure,when that treated with chicken manure was only 1/4 of that with urea.The results also demonstrated that vitamin C and soluble sugar content of the water spinach increased with higher chicken manure treatment,while urea treatment did not show the similar trend.In vegetable production,fertilizers should be chosen and applied carefully to maintain appropriate yield and high quality.