Effects Of Exogenous ABA And SA On Physiological Characteristics Of Winter Wheat Before And After Winter

Wheat is a worldwide food crop.Wheat plays an important role in food production in our country.Wheat is divided into spring wheat and winter wheat and winter wheat,wheat is a cold crop.With the global warming,spring wheat production began to decline significantly,the importance of winter wheat is increasing,'Dongnong Dongmai 1' is The winter wheat cultivars with the highest wintering ability in the alpine region of Heilongjiang Province,which has high cold resistance and high greening rate,have a high research value.In order to explore the effect of exogenous hormones on cold tolerance of cold winter wheat under low temperature stress The winter wheat cultivar of Dongnong Dongmai No.1,a strong cold-resistant winter wheat cultivar Jimai 22(which can tolerate above and below-10 ?)as the experimental material,began from the three-leaf period The samples were treated with salicylic acid(SA)(concentration of 10-3 mol/ L),abscisic acid(concentration of 10-5 mol / L)(ABA)and(SA + ABA)mixed solution(distilled water treatment as blank control)The contents of malondialdehyde(MDA),soluble sugar,soluble protein,antioxidant enzyme and chlorophyll content were measured at 0 ?,-10 ? and-25 ?,respectively.The results showed that the content of malondialdehyde(MDA),soluble sugar,soluble protein,and wheat And morphological features characteristic chlorophyll fluorescence before and after wintering.The main findings are as follows:? the impact of exogenous SA and ABA on photosynthetic characteristics of winter wheatWith the prolongation of low temperature stress,the chlorophyll content of winter wheat was significantly higher than that of the control group.The maximum light quantum yield(Fv / Fm)and non-photochemical quenching coefficient(NPQ)of the two winter wheat decreased with the decrease of temperature and the time of stress,and the actual photon yield(?PSII)and photochemical quenching coefficient(qP)increased with the prolongation of stress time.The results showed that SA and spraying(ABA + SA)could effectively increase the values ? of Fv /Fm,?PSII and qP,and decrease the NPQ value to enhance the photosynthetic activity of wheat.Wherein Exogenous(ABA + SA)mixture treatment better effect for improving the cold resistance of winter wheat.The effect of hormone treatment on the effect of strong winter wheat cultivar Dongnong Dongmai 1 was weak.(ABA + SA)treatment group was significantly higher than that of the control group,indicating that the plants treated with(ABA + SA)still maintained high photosynthetic activity? SA and the impact of exogenous ABA on cold resistance physiological and biochemical indexes of winter wheatWith the decrease of temperature,the relative conductivity,MDA content,soluble sugar and soluble protein content and antioxidant enzyme activity of Dongnong Dongmai 1 were increased,and SA,ABA was sprayed at different temperatures compared with the control group(SOD),peroxidase(POD),catalase(CAT),catalase(CAT),catalase(CAT),peroxidase(POD)and catalase(CAT)were measured by ABA + SA.(ABA + SA)treatment group was more effective than other treatment groups at-10 ?.With the decrease of temperature,the relative conductivity and MDA of Jimai 22 increased,and the content of soluble sugar and soluble protein decreased first and then decreased.Compared with the control group,SA,ABA and ABA + SA could be reduced to different degrees Conductivity,MDA content,and increased soluble sugar and soluble protein content,SOD,POD,CAT activity;-10 ? conditions,the hormone treatment group than the control group effect is more significant.Compared with winter wheat with different cold resistance,the effect of exogenous hormones on Dongnong Dongmai 1 was better than that of Jimai 22.(3)Effects of exogenous SA and ABA on morphological indexes of winter wheatWith the prolongation of low temperature stress,the root length,root number,seedling length and tiller number of winter wheat showed an increasing trend,while fresh weight and dry weight increased first and then decreased.The spraying of fresh ABA could significantly increase the fresh weight of plant.The spraying of SA alone could significantly increase the root number of winter wheat,while spraying(ABA + SA)could effectively increase the root length and increase the dry weight significantly at-10 ?.Compared with the two winter wheat cultivars with different cold resistance,the effect of exogenous hormones on Dongnong Dongmai 1 was better than that of Jimai 22.? reviving rateThe effluent rate of SA,ABA and ABA + SA in Dongtong Dongmai 1 and Jimai 22 increased,But the effect of Donga Dongmai 1 was more obvious,and(ABA + SA)was the best...