The Effect Of ?-ketoglutarate On Winter Wheat Under Drought Stress

Use of water culture method to study the effect of ?-ketoglutarate on winter wheat under PEG simulated drought stress with Yunong 202 as materials,and from the osmotic adjustment,photosynthesis,nitrogen use,etc.to clarify their physiological preliminary mechanism,the main conclusions showed that:(1)Drought stress resulted in reduction of fresh weight of wheat shoots and dry weight,as well as leaf relative water content,R/T increased and dry matter accumulation decreased,reductions amount with the stress level and time increased.The effect of drought stress on shoot fresh weight is bigger than dry weight.?-ketoglutarate may accelerate shoot growth of wheat and conducive to water retention at different PEG concentrations of stress.Among them,the high PEG stress 5mmol·L-1 ?-ketoglutarate effect on wheat was significantly higher than remission 2.5mmol·L-1 ?-ketoglutarate processing,but low PEG concentration of stress the difference was not significant.(2)Chlorophyll a content of wheat was redueced with the drought and the stess time increased.However,the performance of chlorophyll b was contrary.?-ketoglutarate can reduce the effect of drought stress on wheat seedlings of chlorophyll a,chlorophyll a content maintain a high level over an extended period,while ?-ketoglutarate can be further increased chlorophyll b content of wheat seedlings,Especially at high PEG stress effect is obvious.In addition,the added ?-ketoglutarate PEG stress significantly increased photosynthetic efficiency of wheat seedlings,but did not reach the control level.(3)Drought stress increased proline and free amino acids of wheat.?-ketoglutarate can be further improved wheat proline and free amino acid content,the more severe stress the more obvious effects.The promoting effect of 5 mmol·L-1 ?-ketoglutarate on proline and free amino acid content in wheat seedings was greater than 2.5 mmol·L-1 at the same level of drought stress.(4)Drought stress inhibited the absorption of wheat to nitrogen,the absorption rate of wheat to nitrate in nutrient solution is inversely proportional with the stress level and time.Drought stress inhibited nitrogen uptake of wheat and the GS activity,resulting in the amount of nitrogen accumulation of wheat seedlings decreased.?-ketoglutarate could promote wheat seedlings under PEG stress on nitrogen uptake,and increase GS activity,especially high PEG stress and 5 mmol·L-1 ?-ketoglutarate concentration effect is obvious.