Relaxation of Na_2CO_3 stress on Puccinellia tenuiflora (Griseb)Scribn. et Merr.plants by neutralizing with H_3PO_4
Shi Decheng(Life Science College,Northeast Normal University,Changchun 130024)
Puccinellia tenuiflora plants were stressed with 100mmol/L Na2CO3 which were neutralized to various pHsby adding H3PO4.Some strain indexes in the plants were determined.The treatment of neutralizing to pH8achieved the best result in relaxing Na2CO3 stress on Puccinellia tenuiflora plants.In the pH8 treatment,therelative growth rates of shoot and root were respectively more than 58%and 88%of without neutralizedone;the root growth was obviously promoted,which made an increase in root /shoot ratio; the prolinecontent in shoot dropped to the level of no stressed contrast;the citric acid content in shoot had a drop belowthe level of the contrast;the K+ content increased and the Na+ content decreased in roots,the degrees of theincrease in K + and the decrease in Na + were the greatest in shoots;the leakage rate of electrolyte in leavesdropped nearly to the level of the contrast.The experimental results supported that the high pH was themain factor of Na2CO3 stress. It can be expected to neutralize with H3PO4 or other acidic substances as aneffective method to recover alkaline soil.