不同追肥处理对叶菜型甘薯产量、品质及硝酸盐积累的影响

Effects of different topdressing treatments on the yield,quality,and nitrate accumulation of vegetabley sweet potato

为提高黄淮地区叶菜型甘薯产量,改善茎尖品质,明确减施氮肥、配施有机肥在黄淮地区叶菜型甘薯生产中的应用效果及其可行性,以鄂菜薯10号为试验材料,设计单追施氮肥(CK)、单追施有机肥(T1)、有机肥+减量30%氮肥(T2)、有机肥+减量20%氮肥(T3)、有机肥+减量20%氮肥+微生物菌剂(T4)共5个处理,研究不同追肥处理对叶菜型甘薯产量、品质及硝酸盐含量的影响。结果表明,与CK相比,不同追肥处理均能提高叶片总叶绿素含量和抗氧化酶活性,降低硝酸盐含量。其中,T4处理叶片总糖、维生素C、黄酮含量较CK分别显著提高17.27%、13.33%、17.85%,茎尖产量达36917.73 kg·hm^(-2),较CK显著提高19.30%。T4处理硝酸盐含量最低为455.75 mg·kg^(-1),较CK显著降低24.59%。相关性分析表明,菜用甘薯叶片SPAD与产量呈极显著正相关,与蛋白质含量、维生素C含量、POD活性和SOD活性呈显著正相关,与丙二醛含量呈显著负相关。综合分析可知,氮肥96 kg·hm^(-2)+有机肥6000 kg·hm^(-2)+微生物菌剂45 kg·hm^(-2)的追肥模式可有效提高薯尖品质和产量,减少硝酸盐累积,可作为黄淮地区叶菜甘薯的推荐追肥模式。

To increase the yield of vegetabley sweet potato in Huanghuai region,improve the quality of stem tips,and clarify the application effect and feasibility of reducing nitrogen fertilizer and applying organic fertilizer in the production of vegetabley sweet potato in Huanghuai region,the experiment was designed using Eshu No.10 as the test material,with five treatments including single topdressing with nitrogen fertilizer(CK),single topdressing with organic fertilizer(T1),organic fertilizer+reduced nitrogen fertilizer by 30%(T2),organic fertilizer+reduced nitrogen fertilizer by 20%(T3),and organic fertilizer+reduced nitrogen fertilizer by 20%+microbial agent(T4).The effects of different topdressing treatments on the yield,quality,and nitrate content of vegetabley sweet potato were studied.The results showed that compared with CK,different topdressing treatments could increase the total chlorophyll content and antioxidant enzyme activity of leaves,and reduce the nitrate content.Among them,the total sugar,vitamin C,and flavonoid content of leaves in T4 treatment were significantly increased by 17.27%,13.33%,and 17.85%,respectively.The stem tip yield reached 36917.73 kg·hm^(-2),which was significantly increased by 19.30%compared with CK.The nitrate content in T4 treatment was the lowest at 455.75 mg·kg^(-1),which was significantly reduced by 24.59%compared with CK.Correlation analysis showed that SPAD of vegetabley sweet potato was significantly positively correlated with yield,and significantly positively correlated with protein content,vitamin C content,POD activity,and SOD activity,and significantly negatively correlated with malondialdehyde content.Comprehensive analysis showed that the topdressing mode of nitrogen fertilizer 96 kg·hm^(-2)+organic fertilizer 6000 kg·hm^(-2)+microbial agent 45 kg·hm^(-2) can effectively improve the quality and yield of sweet potato tips,reduce nitrate accumulation,and can be recommended as a topdressing mode for vegetabley sweet potato in Huanghuai region.