Alleviating Effect Of Phosphorus On Aluminum Toxicity Of Soybean Cultivars With Different Phosphorus Efficiencies

Soil acidification and aluminum toxicity have always been one of the important factors limiting soybean production.Aluminum stress seriously affects the growth and development of soybean aboveground and underground parts,and ultimately leads to the decrease of grain yield.Phosphorus is involved in many physiological and biochemical processes in plants,and is the main component of energy storage and transport,also the component of phospholipids in cell membranes,which plays an important role in maintaining the structural stability of cell membranes.Aluminium stress of forefathers’ research use ordinary soybean varieties more,this experiment with different phosphorus efficiency of soybean varieties,in sand culture was carried out under the condition of soybean photosynthesis,nutrient accumulation,sugar content and antioxidant enzyme activity index determination,in order to clear regulatory mechanism of phosphorus on aluminum stress,reached through the p management to relieve stress,Reduce the damage of aluminum toxicity associated with soil acidification to soybean growth and development.The main test results are as follows:1.P-efficient soybean varieties of plant height,dry weight,root length,total root length,root surface area,the total number of root and root volume affected by aluminum stress,can be in low phosphorus and phosphorus ease and high phosphorus levels to phosphorus inefficient soybean varieties of plant height,dry weight,root length,total root length,root surface area,the total number of root and root volume affected by aluminum stress,Relief is achieved only at high phosphorus levels.Compared with no Al treatment,low Al treatment promoted plant height,dry weight,taproot length,total root length,total root surface area,total root volume and root tip number of p efficient and P inefficient soybean varieties.2.On the 9th day after treatment,the Al content of underground and aboveground parts of soybean varieties with different P efficiency decreased significantly under medium P level compared with low P efficiency soybean varieties.Different phosphorus efficiency of soybean varieties of underground part after phosphorus processing 18 days of aluminum content compared with 9 days,under high phosphorus treatment,P-efficient soybean roots of aluminum content was reduced by 30% or so,phosphorus inefficient soybean roots of aluminum content reduced 10 ～ 20%,show that P-efficient soybean decreased soybean aluminum content ability better than phosphorus inefficient soybean varieties.3.At the same P concentration level,the contents of N,P and K in aboveground and underground parts of soybean increased firstly and then decreased with the increase of Al concentration,indicating that low al concentration can promote the accumulation of nutrient content in soybean.At the 9th day of treatment,the effects of al stress on P content in overground and underground parts of P efficient soybean could be alleviated at low and medium P levels,while the effects of Al stress on N,P and K content in overground and underground parts of p inefficient soybean could be alleviated only at high P levels.On the 18 th day of treatment,low P,medium P and high P levels alleviated the effects of al stress on NPK content in aboveground and underground parts of P efficient and P inefficient soybean varieties.4.The effects of Al stress on leaf area,net photosynthetic rate and leaf color of soybean seedlings of P efficient soybean varieties could be alleviated under low and medium P levels,but the effects of Al stress on P inefficient soybean varieties could not be alleviated.The effects of Al stress on leaf area,net photosynthetic rate and leaf color of P efficient and P inefficient soybean seedlings were alleviated under high P level.5.Low aluminum concentration can decrease soluble sugar content and sucrose content and increase starch content.The effects of aluminum stress on soluble sugar content,sucrose content and starch content of soybean varieties with high phosphorus efficiency could be alleviated under low and medium phosphorus levels,but the effects of aluminum stress on soybean varieties with low phosphorus efficiency could not be alleviated under low phosphorus levels.The effect of aluminum stress on soluble sugar content,sucrose content and starch content of high phosphorus efficiency and low phosphorus efficiency soybean was alleviated by high phosphorus concentration.6.Low concentration aluminum treatment can reduce the activities of SOD,POD and CAT enzymes in soybean.After 18 days of medium P treatment,the effects of aluminum stress on antioxidant enzyme system of high P soybean varieties were alleviated.However,the balance of protective enzyme system of low P soybean varieties was destroyed due to not being alleviated.High P treatment for 18 days can alleviate the effect of aluminum stress on antioxidant enzymes of soybean varieties with high P efficiency and low P efficiency,without destroying the balance of protective enzyme system.