Effect Of Calcium And Boron On The Soybean N, P, K Nutrients Uptake, Growth And Yield

Experiments on the effect of Calcium and Boron on soybean(Glyssine max.L)macronutrients were conducted in pots at the greenhouse of Guangxi University in 2006.The objectives of this study were to determine the effect of Calcium,boron and calcium+boron:(â… )on the soybean's N,P,K;(â…¡)on the soybean's agricultural characters;(â…¢)on the soybean nodulation and yield.Calcium and Boron were applied to the soil in following treatment:Calcium(g/pots)0,3.5,4.5,5.5,6.5,7.5,Boron(mg B/pots)15,25,35,45, 55 and Calcium Boron(g Ca+mg B/pots)as following:(3.5+55),(3.5+15), (5.5+35),(7.5+55),(7.5+15).The results are following:The application of Ca increased soybean nodules,soil pH values,soybean leaf area,and the chlorophyll content.It increased the nitrogen and phosphorous contents of the leave,root and seed.The soybean yield was increased with the application of Ca.The plant leaves,root and seed had fewer and lower potassium content in the condition of increasing Ca concentration.B application revealed an increasing of leaves and seed nitrogen content, but showed decreased root nitrogen content.It inhibited significantly leaves and seed phosphorous content and reduced leaves,root and seed potassium content. Root phosphorous content was highest in the medium B treatment(B3). Significantly decrease was observed in soil pH,nodule number,leaf area, chlorophyll and the dry matter with the application of B.Ca+B application showed an increasing content of nitrogen in the leaves and seed.But,higher B concentration treatments(Ca1+B5,Ca5+B5)reduced root nitrogen content,decreased leaves,root phosphorous,inhibited leaves,root and seed potassium content.B toxicity symptoms were clearly apparent on the soybean plant:leaves area,nodules,chlorophyll and the dry matter decreasing when the soybean received higher level of B.It also reduced the soybean yield and economic coefficient.Lower B concentration treatments(Ca1+B1,Ca5+B1) increased root nitrogen content,leaves phosphorous content,and leaves,root and seed potassium content.Soybean yield and economic coefficient were highest when Ca was applied with low concentration of B.However,the role of Ca+B ratio on the behavior of plant nutrients is still not well defined,and further experimentations are desirable in this field.