Effects Of Different Valence Selenium And Selenium-sulfur Interaction On Wheat Agronomic Traits And Physiological Indexes

Selenium is a beneficial element of plants,but different plants have different abilities to absorb and accumulate selenium.The type and concentration of selenium and the participation of other elements affect plant growth.Studies have shown that the mechanism of absorption and transportation of sulfate and selenate by plants is similar,but related research needs to be further studied.In this paper,by determining the effects of different concentrations of selenate,selenite and sulfate on wheat agronomic and physiological traits,the optimal wheat growth concentration was determined,the effect of sulfate on the absorption of selenate was discussed,and sulfate was used to regulate and control selenate Absorption.Taking Donghei No.1 and Luohan No.6 as test materials,on the basis of setting up complete nutrient solution and sulfur-deficient nutrient solution treatment,sodium selenite and selenium were added 1,2,5,10,20 μmol/L,respectively Sodium sulfate was used to determine the agronomic traits of wheat grown under different treatments,the activity of antioxidant defense system,and the effect of exogenous selenium on the kinetic parameters of wheat chlorophyll fluorescence.(1)The concentration range suitable for wheat cultivation is sodium selenium concentration of 1-2μmol/L and sodium selenite concentration of 1-20 μmol/L(2)Low concentration sodium selenate(<10 μmol/L)will promote the growth of wheat,and high concentration sodium selenate(≥10 μmol/L)will inhibit the growth of wheat;different wheat varieties have different sensitivity to selenium,The absorption capacity of selenium is also different,Luohan 6 is more affected under the same treatment.Sodium selenite culture concentration below 20 μmol/L promotes wheat growth.When sulfur is deficient,the growth of wheat is significantly inhibited.When cultured with sodium selenate,low concentration sodium selenate(<5 μmol/L)treatment will alleviate the stress of sulfur deficiency on wheat growth to a certain extent.Sodium selenite(≥5 μmol/L)treatment will reduce the activity of wheat’s antioxidant defense system to a greater extent.In both cases of sulfur deficiency,sodium selenite appears to promote wheat growth.(3)Sulfur deficiency is less than the concentration of selenium stress when cultured in complete nutrient solution,respectively 5 μmol/L and 10 μmol/L,and the stress is more serious at high concentration.By comparing the concentration and degree of selenium stress,it shows that Wheat’s ability to absorb selenium is enhanced when sulfur is deficient,and there is antagonism between the absorption of selenium and sulfur.When exogenous selenium is applied,the application of sulfur can be appropriately reduced to increase the absorption of selenium by wheat;sulfur can also be applied to alleviate the production of selenium Coercion.In this paper,by monitoring the changes of agronomic traits,physiological indicators and chlorophyll fluorescence parameters during wheat cultivation,the effects of the interaction of different valence selenium and sulfur on wheat growth were analyzed,and the effects of selenate on promoting growth and producing toxicity under different conditions were determined.Concentration,the promotion effect of selenite on wheat growth was also detected,and the mitigating effect of selenium under wheat sulfur deficiency stress was found,which provided a theoretical basis for the reasonable use of different selenium sources in wheat production.