Distribution characteristics of organic selenium in different parts of vegetable jute at different growth stages

【Objective】To explore the distribution characteristics of organic selenium in different parts of vegetable jute during different growth periods and to provide theoretical basis and technical guidance for the production of seleniumrich vegetable jute.【Method】The experiment was conducted on the medium selenium soil with a total selenium content of 0.221 mg/kg and a pH of 6.02, the Corchorus capsularis Guimacai 1 and Guimacai 2 were used as the materials. The contents of protein selenium, selenocysteine and selenomethionine in roots, stems, leaves, capsules and total selenium content in leaves at the harvesting stage(seedling stage, topping stage and flowering stage) and capsule stage were determined respectively.【Result】The contents of protein selenium, selenocysteine and selenomethionine in each part of the two varieties were 0.034-0.173 mg/kg, 2.857-16.053 μg/kg and 26.076-135.235 μg/kg, respectively. The contents of organic selenium at harvesting stage of the two varieties were leaves>roots>stems. At the capsule stage, the organic selenium content in each part was leaves>roots>capsules>stems, the organic selenium content of leaves was significantly higher than that of stems(P<0.05, the same below). With the prolongation of growth period, the content of organic selenium in the leaves and roots of the two varieties reached the highest value at capsule stage, which was significantly higher than that in seedling stage. The content of organic selenium in the stems reached the highest value at the topping stage, and significantly higher than that at the flowering stage and capsule stage. The total selenium content in the leaves of the two varieties during the harvesting stage was 96.739-106.023 μg/kg and 113.778-137.841 μg/kg, respectively. The selenium amino acids accounted for 74.351%-80.098% of the total selenium content, which all met the requirements of selenium-rich agricultural products product standard(>65%) in Guangxi.【Conclusion】Leaf is the main part of organic selenium distribution in vegetable jute. The capsule stage is key period of selenium uptake by leaf and root. The edible parts of Guimacai 1 and Guimacai 2 can meet the requirements of selenium-rich agricultural products, when they are planted in medium selenium soil. So they can be promoted as selenium-rich vegetables in middle-selenium soil area.