Research On The Effect Of Selenium Application Technology In Winter Wheat

The advantages of selenium resources in Hubei are remarkable.The two selenium-enriched belts in the Enshi and Jianghan Plains run through the province,and the total selenium resources are in the forefront of the country.The Jianghan Plain and surrounding areas are the largest commercial grain bases in Hubei Province.According to the survey,selenium-enriched soil resources are distributed.The soil selenium content is in the range of 0.2-0.4 mg·kg^-1,which is between the selenium-middle and selenium-rich soils.The selenium content of the crop is on the edge of selenium-rich levels.According to the development plan of selenium-enriched industry in Hubei Province,in order to use Hubei selenium resources efficiently,the production and development of selenium-enriched agricultural products will be carried out in Jianghan Plain,and the comprehensive production capacity will be increased to increase farmers’income.In this study,winter wheat was selected as the material.Based on the soil selenium resources in Jianghan Plain,the selenium content and grain quality of wheat were improved by exogenous application of selenium to achieve high-quality agricultural production.The effects of exogenous selenium application,morphology,concentration,selenium application rate and period on selenium uptake,transport,accumulation and distribution in winter wheat were systematically studied.The application effect of selenium application on selenium level and food safety of winter wheat was evaluated.The set of selenium-enriched technology provides technical support for the production of selenium-rich wheat in Jianghan Plain.The main conclusions are as follows:（1）The effect of foliar spray selenium is significantly better than that of soil-based selenium ore.The soil-based application of selenium ore powder is 500 kg·hm^-2,and the selenium content of wheat grain is 375.04μg·kg^-11 at maturity.45 g·hm-2 sodium selenite and sodium selenate are sprayed on the wheat heading stage.The selenium content was760.5μg·kg^-11 and 736.42μg·kg^-1,respectively,which was significantly higher than that of soil.In addition,selenium is mainly concentrated in the roots after the application of selenium ore in the soil,and the selenium content in the root is 2416.78μg·kg^-1.For the selenium treatment on the foliar surface,the selenium content in the root of the wheat is in the range of 580.47-617.91μg·kg^-1.After applying selenium ore powder,it is difficult for wheat selenium to be transported to the aboveground part,and the amount of selenium ore powder is large and the cost is high.Therefore,foliar spray selenium is preferred in production.（2）The difference of selenium content in wheat grain was not significant.Spraying45 g·hm^-2sodium selenite and sodium selenate during wheat heading and flowering stage,the difference of selenium content in wheat seeds treated with two selenium forms was only 24.09μg·kg^-1and 27.35μg·kg^-1.The difference in selenium utilization rate of wheat kernels is also within 2%.Therefore,the effects of selenite and selenate on wheat selenium absorption are not significant.（3）The difference of selenium content in wheat grain was not significant.In the pot experiment,in the case of 3 mg of selenium per pot,sodium selenite is suitable for spraying at a concentration of 100 mg·L^-1;for sodium selenate,the spraying concentration is 300 mg·L^-1is more suitable.The study found that foliar application of 30 mg·L^-1and300 mg·L^-11 two concentrations of exogenous selenium 30mL and 10mL.The low-concentration exogenous selenium was sprayed during the flowering stage,and the selenium content of wheat grain was 1958.06μg·kg^-11 under sodium selenite treatment.The selenium content of wheat grain under the treatment of sodium selenate was 1516.92μg·kg^-1,and the high concentration was applied.The selenium content of wheat selenium and sodium selenite was 1436.20μg·kg^-1,and the selenium content of wheat grain treated with sodium selenate was 1994.94μg·kg^-1,indicating that low concentration selenium was disposed when sodium selenite was sprayed.Good fertilizer;when spraying sodium selenate,it is suitable to use high concentration of selenium fertilizer.On the spraying times,multiple spraying of selenium can increase the selenium accumulation of wheat grain,spraying 300 mg·L-1 sodium selenate at heading stage,heading stage and flowering stage,and the selenium content of wheat grain is 982.69μg·kg^-1,1277.50μg·kg^-1,1994.94μg·kg^-1,the difference of selenium content in single-spray selenium wheat and the selenium content of three-spray selenium wheat was not significant,indicating that selenium absorption in wheat is continuously accumulated.In the process,winter wheat is more tolerant to selenium.In actual production,selenium can be sprayed once at an appropriate time.（4）Foliar spraying period significantly affected the absorption and transport of selenium in wheat,and spraying at the flowering stage was the best period for selenium-enriched wheat production.The results of pot experiment and field experiment in the first year showed that the selenium-spanning period had the most significant effect on the selenium accumulation of wheat.Therefore,in the second year,multiple time gradients were set in the field experiment,and selenium treatment was started from the wheat heading stage.Spray selenium until the wheat matures.The results showed that the selenium content of wheat seeds reached the highest value in the initial stage of flowering,in which the selenium content of wheat seeds was 1275.79μg·kg^-1,and the selenium content of seeds treated with selenate was 1408.93μg·kg^-1.The selenium content of wheat seeds was the lowest at the heading stage,and the selenium content of the seeds was 720.97μg·kg^-1and 718.52μg·kg^-1,respectively.From the whole period of selenium spraying,the increase of selenium content in the late stage of wheat growth（the flowering-filling stage）was greater than that in the early growth stage（the heading stage-flowering stage）,and the most suitable for the selenium accumulation of wheat.The selenium spraying period is the flowering period.（5）Applying selenium can increase the yield and quality of wheat grains.From the perspective of wheat grain yield,the 1000-grain weight of wheat grain was about 45.75 g after selenium treatment,and the 1000-grain weight of blank control was 44.35 g.Foliar application of selenate could increase the 1000-grain weight of wheat grain,and then increase grain yield to some extent.From the perspective of grain quality,the protein content of wheat after spraying selenium was about 158.82 g·kg^-1,the protein content without selenium treatment was 134.09 g·kg^-1,and the total selenium content of wheat organic selenium was 80.18-87.22%,the difference between the selenium source and the selenium release period is not significant.In summary,the selenium-sprayed method was used to produce selenium-enriched wheat,and sodium selenate was sprayed during the flowering stage of wheat.The amount of selenium applied was 45 g·hm^-2and the concentration was 300 mg·L^-1.According to the World Health Organization,the selenium intake of human body needs 50-200μg·d^-1,and the daily intake of 50-100 g is produced by this method.The selenium-enriched wheat can meet the human body’s demand for selenium nutrition and achieve selenium and a safe level.