不同施磷水平对分蘖洋葱伴生番茄幼苗生长及菌根侵染的影响

Effects of Phosphorus Fertilizations on Growth and Root Mycorrhizal Infection of Tomato Seedlings Intercropped with Potato-onion

【目的】探究不同施磷水平对分蘖洋葱伴生番茄的幼苗生长及根系菌根侵染的作用,明确适宜磷肥施用量进而最大程度发挥植物种间正相互作用,有利于维持农业生态系统的稳定性与生产力。【方法】以番茄(Solanum lycopersicum L.)和分蘖洋葱(Allium cepa L.var.aggregatum G.Don)为试验材料,通过番茄单作(T)和分蘖洋葱伴生番茄(TO)盆栽试验,研究其在0 mg·kg^(−1)磷肥(P0)、250 mg·kg^(−1)磷肥(P250)、500 mg·kg^(−1)磷肥(P500)、1000 mg·kg^(−1)磷肥(P1000)施磷水平下,番茄植株生物量大小、番茄根系菌根侵染率、番茄植株养分浓度及土壤养分含量的变化情况。【结果】与P0相比,P250、P500、P1000施磷水平下,单作番茄全株干重分别增加了43.18%、47.73%和47.02%,伴生番茄全株干重分别增加了45.93%、50.36%和40.89%,且各施磷水平下,伴生番茄全株干重与单作番茄相比分别增长了8.8%(P0)、13.6%(P250)、15.2%(P500)及5.6%(P1000)。同时,施磷水平为P250、P500、P1000时,番茄植株生物量、植株养分浓度、植株养分吸收量、土壤有效磷及速效钾含量均显著高于施磷水平P0,且番茄植株生物量与植株氮磷钾养分和土壤有效磷含量间呈显著正相关。另外,施磷水平为P500时,番茄根系菌根侵染率和植株生物量最高,均显著高于其他施磷水平。【结论】磷营养在番茄和分蘖洋葱种间正相互作用中发挥了重要作用,其中施磷水平为P500时,能最大程度发挥番茄和分蘖洋葱间的正相互作用,增加番茄根系菌根侵染率,协助番茄根系从土壤中获取养分,进而促进番茄的生长。

【Objective】Roles of phosphorus application on growth and root mycorrhizal infection rate of tomato seedlings intercropped with potato-onion were investigated to optimize the fertilization for sustainable crop production and agricultural ecosystem.【Methods】Tomato(Solanum lycopersicum L.)seedlings were either grown under monoculture(T)or intercropping with potato-onion(Allium cepa L.var.aggregatum G.Don)(TO)in a pot experiment.Biomass,root mycorrhizal infection rate,and nutrient concentrations of the tomato plants,as well as the nutrient contents in the soil treated with varied phosphorus applications,i.e.,0 P(P0),250mg P·kg^(−1)(P250),500mg P·kg^(−1)(P500),and 1,000mg P·kg^(−1)(P1000),were monitored.【Results】Compared to P0,the dry weight of the monocultured tomato plant under P250 increased by 43.18%,under P500 by 47.73%,and under P1000 by 47.02%,while the intercropping under P250 resulted in an increase of 45.93%,under P50050.36%,and under P100040.89%.At same P application level from T to TO,the tomato plant weight increased 8.8%under P0,13.6%under P250,15.2%under P500,and 5.6%under P1000.P250,P500,and P1000 enhanced the biomass production as well as the nutrient concentration and uptake of the tomato plants.The applications also increased the available P and K in soil with a significant positive correlation.At P500,the greatest and significantly higher than other treatments on plant biomass and root mycorrhizal infection rates of the tomato plants were observed.【Conclusion】P played an important role in the interaction between tomato and potato-onion.At the 500 mg·kg^(−1) application level,P maximized the interaction and enhanced the tomato root mycorrhizal infection which facilitated transfer of nutrients from soil to plant promoting the growth.