滴灌水肥一体化条件下番茄氮肥适宜用量探讨

Study on the suitable amount of nitrogen fertilizer for tomato under drip irrigation and fertilizer integration

利用田间小区7年定位试验,研究了滴灌水肥一体化条件下,不同化肥施氮量结合基施有机肥对番茄产量、品质、硝态氮累积、土壤电导率及土壤p H值的影响。结果表明:1)与不施氮相比,施肥可显著提高番茄产量,但过量施肥不仅不会提高番茄产量,还会降低番茄品质; 2)施氮量对土壤硝态氮的累积有较大的影响,随施氮量的增加,土壤剖面硝态氮累积量增加,其中对0～20 cm土层硝态氮累积量的影响最为显著; 3)土壤硝态氮含量与土壤电导率呈极显著相关关系,表明施氮量越高,电导率随之增加越显著,土壤的次生盐渍化风险越高; 4)除CK处理外,其它处理土壤硝态氮含量与p H值呈极显著负相关关系。综合考虑产量、品质与土壤环境质量,推荐华北温室秋冬茬番茄施用200 kg/hm^2有机N+250 kg/hm^2无机N,P2O575 kg/hm^2,K2O 450 kg/hm^2为宜。

Based on the 7-year field experiment,the effects of different nitrogen rates of chemical fertilizers combined with organic fertilizers on the tomato yield,quality,nitrate accumulation,soil electrical,conductivity and soft pH were studied under the conditions of drip irrigation and fertilizer integration.The results showed that:1)Compared with no nitrogen fertilizer, fertilization could significantly increase the yield of tomato,but over-fertilization will not only decrease the yield of tomato,but also reduce the quality of tomato;2)Nitrogen application had a greater effect on nitrate accumulation in soil,with the increase of nitrogen application,the accumulation of nitrate nitrogen in soil profile increased,and the effect on nitrate accumulation in 0-20cm soil layer was the most significant;3)Soil nitrate nitrogen content and soil conductivity was highly significant correlated,indicating that the higher nitrogen application,the more significant of the conductivity increase,and the higher the risk of soil secondary salinizafion;4)In addition to CK treatment,the contents of nitrate nitrogen in other treatments showed extremely significant negative correlation with pH value.Considering the yield,quality and soil environmental quality,it was recommended that the application of 200kg/hm^2organic N +250kg/hm^2 inorganic N,P2O5 75kg/hm2,K2O 450kg/hm^2 was appropriate.