小麦蚕豆间作条件下不同施氮量对作物根际微生物数量的影响*

 通过盆栽试验和室内平板培养技术研究了小麦蚕豆间作条件下不同施氮量对作物根际微生物的影响。结果表明：小麦蚕豆根际微生物数量在总体上以细菌为主，放线菌次之，真菌最少。在作物各生育期，随着施氮量的增加，小麦、蚕豆根际微生物数量增加，在施氮量为325 mg/kg（N）时达到数量最高，高氮（N_3/2, 487.5 mg/kg）时下降。在小麦孕穗（蚕豆开花）期施氮量为325 mg/kg 时，间作小麦根际细菌、真菌和放线菌分别比对照（N₀）增加了71%,152%,4%；间作蚕豆根际细菌、真菌和放线菌分别比对照（N₀）增加了214%,65%,17%。小麦与蚕豆间作对小麦根际微生物数量表现为增加作用，但对蚕豆根际微生物的影响相反；间作小麦根际细菌、真菌数量在分蘖期、收获期显著高于单作小麦，间作蚕豆根际微生物数量在施氮量为325 mg/kg（N）时均低于单作蚕豆。施氮量与种植模式的互作效应在蚕豆分枝、开花和鼓粒期对蚕豆根际细菌、真菌有显著影响，对小麦根际细菌仅在分蘖期有显著影响，对小麦根际真菌仅在孕穗期有显著影响。

Effects of Nitrogen Supply Levels on the Amount of Rhizosphere Microorganism of Crops in Wheat and Broad Bean Intercropping

The effects of nitrogen supply levels on the rhizosphere microorganism of crops were studied in wheat and broad bean intercropping.The results indicated that the amount sequence of microorganism in the rhizospheres of wheat and broad bean was bacteria > fungi > actinomyces;the amount of rhizosphere microorganisms of wheat and broad bean increased with the increase of nitrogen supply,the highest amount of microorganisms in rhizosphere of both crops was gained through the treatment of 325mg/kg nitrogen.The amount of microorganisms in rhizosphere of both crops decreased with the supply of high nitrogen(487.5mg/kg).Compared with N0 treatment(control),the amounts of rhizosphere bacteria,fungi and actinomyces of wheat significantly increased 71%,152% and 4%,respectively,by the treatment of 325mg/kg nitrogen during wheat booting stage in intercropping,and those of broad bean increased 214%,65% and 17%,respectively during broad bean flowering stage in intercropping.Intercropping with the treatment of 325mg/kg nitrogen significantly enhanced the amount of rhizosphere microorganisms of wheat,but had the inhibitory influence on that of broad bean.Intercropping significantly increased the amount of bacteria and fungi in the rhizosphere of wheat compared with wheat monoculture during wheat tillering and harvest stage,but it reduced the amount of microorganisms in the rhizosphere of broad bean with the treatment of 325mg/kg compared with broad bean monoculture.The interactions of nitrogen supply and cropping pattern could significantly affect the rhizosphere bacteria and fungi of broad bean during broad been ramifying,flowering and seed pumping stages,while it also significantly affected the rhizosphere bacteria of wheat during wheat tillering stage and fungi of wheat during wheat booting stage.