| Selenium is one of the essential micronutrients for animals and humans.Selenium deficiency can lead to Keshan disease and other diseases.But selenium needs to be consumed in a reasonable amount while the body is replenishing selenium,because the boundary between nutrition and toxicity of selenium is narrow.Plants are an important part of the food chain and are the safest and most effective way for humans and animals to get selenium.Buckwheat is a potential selenium-enriched crop,which has rich nutrition and good health function.In order to research the effects of selenium application on yield,grain selenium,flavonoids,rutin and total phenolics of tartary buckwheat in Jinzhong and the northwest area of Shanxi province,the experiment was conducted simultaneously in the experimental fields of these two areas using orthogonal experimental design.Therefore,the safe selenium application of tartary buckwheat was determined.The main results are as follows:1.Results of study on selenium application in Jinzhong area(1)The results of intuitive analysis showed that the best yield combination of yield was 8.22 g/hm~2 sodium selenite sprayed on the leaves of "Heifeng 1 hao" at the early stage of flowering,the best combination of flavonoid content in the grain was 8.22 g/hm~2 sodium selenite sprayed on the leaves of "Jinqiao 2 hao" at branching stage or early flowering stage,the best combination of rutin content in the grain was 12.33 g/hm~2 sodium selenite applied in the soil during the branching period of "Jinqiao 2 hao",the best combination of total phenol content in the grain was 2.74 g/hm~2 sodium selenite sprayed on the leaves of "Jinqiao 2 hao" at the early flowering stage,the best combination of selenium content in the grain was 27.7425 g/hm~2 sodium selenite sprayed on the leaves of "Heifeng 1 hao" at the early flowering stage.(2)The results of regression modeling showed that the yield of tartary buckwheat in Jinzhong area reached maximum when the variety was "Heifeng 1 hao" and selenium concentration was 13.0367 g/hm~2.The highest content of flavonoid,rutin and total phenol in grain was achieved when the variety was "Jinqiao 2 hao" and the concentration of selenium was 12.25 g/hm~2,12.5 g/hm~2 and 21.5 g/hm~2 respectively.(3)Combining the results,it was concluded that the concentration of 2.74 g/hm~2 sodium selenite applied to the leaves or soil of tartary buckwheat at the early stage of flowering can reach the national safe selenium-enriched standard on the basis of the higher grain yield,selenium content,flavones,rutin and total phenol content.2.Results of study on selenium application in northwest Shanxi Province(1)The results of intuitive analysis showed that the best combination of yield was 8.22 g/hm~2 sodium selenite applied in the soil during the peak flowering stage of "Jinqiao 6 hao",the best combination of flavonoid content in the grain was 12.33 g/hm~2 sodium selenite sprayed on the leaves of "Jinqiao 6 hao" at the early flowering stage,the best combination of rutin content in the grain was 12.33 g/hm~2 sodium selenite applied in the soil or sprayed on the leaves during the early flowering stage of "Jinqiao 6 hao",the best combination of total phenol content in the grain was 2.74 g/hm~2 sodium selenite sprayed on the leaves or applied in the soil of "Jinqiao 6 hao" at the early or peak flowering stage,the best combination of selenium content in the grain was 27.7425 g/hm~2 sodium selenite sprayed on the leaves of "Heifeng 1 hao" at the peak flowering stage.(2)The results of regression modeling showed that grain yield,flavonoid,rutin and total phenol contents of tartary buckwheat in northwest Shanxi were the highest contents when the variety was "Jinqiao 6 hao" and the concentration of selenium was 9.6451 g/hm~2,13 g/hm~2,10 g/hm~2,4 g/hm~2 respectively.(3)Combining the results,it was concluded that the concentration of 5.48 g/hm~2 sodium selenite sprayed on the leaves or 8.22 g/hm~2 sodium selenite applied in the soil of tartary buckwheat at the early flowering stage can reach the national safe selenium-enriched standard on the basis of the higher grain yield,selenium content,flavones,rutin and total phenol content.3.Product of safe selenium application in tartary buckwheatCombining the results of studies in Jinzhong and northwestern Shanxi,the maximum selenium content of grain was less affected by the time and variety of selenium application,and more affected by the way and concentration of selenium application.The safe selenium content of grain was less affected by the variety and the way of applying selenium,and more affected by the time and concentration of applying selenium.At the same time,the basic selenium content of soil has a great influence on the selenium concentration needed to obtain the safe selenium content of seeds.The grain yield,flavonoid,Rutin,total phenol and selenium contents of the same tartary buckwheat variety were different in different ecological areas under the same selenium application method and the same concentration of disodium selenite in the same growth period.Therefore,in the actual production should be based on its ecological zone to develop a suitable program to produce selenium-safe and efficient nutrition fortified buckwheat. |
