摘要
合理施肥对保障土壤质量和粮食安全具有重要作用。有机肥促进土壤生物群落的发展已被认为是其优于化肥的重要方面,然而有机肥影响下的土壤生物群落对作物生长的贡献却了解甚少。了解土壤生物因素对作物抗虫性的贡献不仅可以揭示施肥影响土壤功能的生物调控机制,而且有助于制定土壤–作物的综合管理措施。本研究采集长期施用有机肥和化肥的水稻土,通过制备灭活与否的土壤悬液,在砂培条件下探究土壤生物群落对水稻生长及其抗虫性的影响。结果显示,土壤生物群落和施肥措施均极显著地影响了土壤养分含量(P<0.01)。土壤生物的存在降低了土壤铵态氮含量、水稻生物量、茎叶全氮含量以及褐飞虱(Nilaparvata lugens)生物量;增加了土壤硝态氮含量、水稻的根冠比及水稻根系全氮、可溶性糖以及酚类含量(P<0.05);同时,有机肥处理的土壤生物群落还能够促进水稻茎叶可溶性糖和酚类的合成。接入褐飞虱后,土壤生物群落的存在显著降低了水稻整体的全氮含量,促进了酚类的合成(P<0.05)。研究结果表明,土壤生物群落,尤其是有机肥处理的土壤生物群落,主要通过改变水稻养分向地下部的分配格局、增加根冠比、促进防御性代谢物质(如酚类)的合成来提高水稻地上部对害虫的抗性。
Fertilization plays an important role in soil quality, food supply and security. Although promoting soil biological development is considered as one of the most critical components that organic fertilizers exert on soil compared with chemical fertilization, less attention has been paid to the fertilization-derived influence on crop growth and insect-resistance via soil biota. Understanding the role of soil biota in crop growth and resistance to insects would not only help explain the biological mechanisms of the fertilization effects on soil functions, but also help identify integrative management techniques for soils and crops. Soil suspension was extracted from long-term organically fertilized soils and chemically fertilized soils. Then, the soil suspension was sterilized or non-sterilized to investigate the soil biota＇s effects on rice growth and insect-resistance through a soil-free cultured method. Results showed that soil biota and fertilization significantly affected soil nutrient status（P〈0.01）. Soil biota decreased soil ammonium content, rice biomass, shoot nitrogen content and the biomass of Nilaparvata lugens, but increased soil nitrate content, rice root-shoot ratio and the contents of root nitrogen, soluble sugar and phenolics（P〈0.05）. Meanwhile, soil biota from organically fertilized soils promoted the synthesis of shoot soluble sugar and shoot phenolics. With the addition of Nilaparvata lugens, soil biota significantly reduced rice nitrogen uptake and promoted phenolic synthesis（P〈0.05）.Collectively, soil biota, especially from organically fertilized soils, promoted rice resistance traits by altering the nutrient allocation of rice between aboveground and belowground, and by increasing the root-shoot ratio and the synthesis of phenols.
出处
《生物多样性》
CAS
CSCD
北大核心
2016年第8期907-915,共9页
Biodiversity Science
基金
国家自然科学基金(31170487)
中央高校基本科研业务费项目(KYTZ201404)
江苏省高校优势学科建设工程项目(PAPD)
