Effects Of Upland Rice/soybean Intercropping Managtement And Arbuscular Mycorrhizal Colonization On Nitrogen And Phosphorus Absorption

Intercropping is important management in agricultural production.Intercropping management constitutes multi-level and multi-function group by different crops to develop resources.Intercropping management can use the resources of light,nutrients,water,and oxygento enhance production.Arbuscular mycorrhizal fungi are common beneficial microbe in soil.About 80%terrestrial plants colonize mycorrhizal fungi to form mycorrhiza.Arbuscular mycorrhiza can promote nutrient absorption of host plants and improve the resistance of plants.This thesisstudied nitrogenand phosphorus absorption by upland rice and soybean in intercropping management.Intercropping effects were studied in different plant growth periods,different nitrogen level fertilization and arbuscular mycorrhizal colonization.The intercropping advantages on nigrogen and phosphorus aborption were studied on 4 periods of plant growth,31evels of N application,and arbuscular mycorrhizal colonization.The intercropping advantages were showed by determination of plant growth,N absorption,P absorption and yield.In addition,the effect of AM effect in upland rice/soybean intercropping management was demonstrated by improvement of nitrogen and phosphorus absorption.The main results were as follows:(1)The intercropping advantages of upland rice/soybean were differentin different growth stages of plants.The grain yield increased significantly in intercropping management.Compared to monocropping management,the yield of upland rice and soybean were increased by 21%and 14%,respectively.The land equivalence ratio of upland rice/soybean intercropping management was 1.21.The improvement of crop yield resulted from the increases ofnitrogen and phosphorus absorption on intercropping management.Compared to upland rice monocropping management,nitrogen absorption of upland rice root was increased remarkably in intercropping management._Compared to soybean monocropping management,nitrogen absorption of soybean was_improved in intercropping management.Phosphorus absorption improvement by intercropping management was different in each growth period.Compared to monocropping management,phosphorus absorption of upland rice shoot increased by 48%?36%and 27%in jointing stage,booting stage and maturation stage,respectively.At the time of the booting stage and maturation stage of upland rice,soybean was in the stages of pod and maturation.Phosphorus absorption of soybean root was enhanced by 172%and 98%at pod stage and maturation stage,respectively.(2)On the soil of available nitrogen 68 mg kg-1,incropping advangement of upland rice/soybeanwere different in different quantity of nitrogen fertilizer.On the 50 mg·kg-1(N1)N fertilization,upland rice/soybean intercropping management increased biomass of upland rice and soybean by 24%and 16%respectively.On 100 mg·kg-1 N(N2)application,intercropping management increased biomass of upland rice by 20%.On 150 mg·kg-1 N(N3)application,the crop biomasses were not improved by upland rice/soybean intercropping management.Therefore,with the increased of the amount of nitrogen fertilization,the intercropping advangement on plant growth decreased.(3)Compare to monocropping management,the number andbiomass of soybean root nodule was improved by upland rice/soybean intercropping management.Upland rice/soybean intercropping management enhanced the activity ofnitrogen fixing enzyme of soybean root nodule in intercropping management to some extent.Therefore,upland rice/soybean intercropping management increased root nodulegrowth and efficience of nitrogen fixationof soybean.At N1 level nitrogen fertilization,intercropping management improved both nitrogen and phosphorus absorption of upland rice by 27%.Nigrogen and phosphorus absorption of soybeanin intercropping management was increased by 20%and 12%,respectively.At N2 level of nitrogen fertilization,compared to monocropping management,nitrogen and phosphorus absorption of upland rice in intercropping management increased by 19%and 24%,respectively.Nitrogen and phosphorus absorption of soybean in intercropping management were enhanced by 17%and 47%,respectively.(4)In the upland rice/soybean intercropping system,arbuscular mycorrhizal colonization improved upland rice/soybean intercropping advangement.In upland rice/soybean intercropping management,nitrogen and phosphorus absorption in upland rice and soybean were increased significantly by arbuscular mycorrhizal network between upland rice and soybean.Compared to nonmycorrhizal crops,nitrogen absorption of monocropping and intercropping upland rice were increased by 31%and 37%by mycorrhizal colonization,respectively.Phosphorus absorptions of upland rice in monocropping and intercropping were improved by 11%and 17%by arbuscular mycorrhizal colonization in monocropping and intercropping management,respectively.(5)Compared to monocropping management,upland rice/soybean intercropping management promoted the frequencyand intensity of arbuscular mycorrhizal colonization.It suggested that upland rice/soybean intercropping management facilitated arbuscular mycorrhizal colonization in upland rice and soybean.