Effects Of Selenium On Seed Germination And Early Seedling Growth And Development Of Perilla

Selenium is one of the essential trace elements for human and animals.Perilla is a traditional cultivated plant in China with a long history of cultivation.Perilla plants contain many kinds of special functional substances which are beneficial to human and have high comprehensive utilization value.In this study,two ecologically different Perilla cultivars ZB-1(leaf green)and ZB-3(leaf purple)were selected as materials to study the effects of selenium(Na2Se O3 as donor)on seed germination and growth of Perilla.Effects of selenium hydroponics and foliar spraying on the growth and development of early seedling of Perilla sinensis in order to provide theoretical basis for the application of selenium in Perilla cultivation and production.The main research results are as follows:1.Selenium(donor Na2 Se O3)aqueous solution showed low concentration promotion and high concentration inhibition on the germination and growth of seeds of two Perilla varieties.Selenium of less than 10 μM promoted seed germination and growth,while selenium of more than 10 μM inhibited seed germination and growth.The root length of seeds of ZB-1 and ZB-3 varieties treated with 10 μM se increased by 33.0% and 54.5%,respectively.The germination rate,germination potential,germination index and vigor index of seeds were significantly higher than the control group.2.Low concentration of selenium(0.2,0.4,0.8 μM)hydroponics promoted the growth of two Perilla cultivars.Hydroponics with high concentration of selenium(1.6,3.2,6.4 μM)inhibited the growth of two Perilla cultivars.0.4 μM selenium had the best effect on the growth of ZB-1 seedlings.The seedling plant height,stem,leaf and root fresh weight were significantly higher than those of the control group,and 0.8μM selenium had the best effect on the growth of ZB-3 seedlings.3.Water culture with low concentration of selenium(0.2,0.4,0.8 μM)promoted the photosynthesis of the two Perilla cultivars,and the photosynthetic rate and chlorophyll content of the leaves of the seedlings were higher than those of the control group.Hydroponics with high concentration of selenium(1.6,3.2,6.4 μM)inhibited the photosynthesis of the two Perilla cultivars,and the photosynthetic rate and chlorophyll content of the leaves of the seedlings seedlings were lower than those of the control group.The effect of 0.4 μM selenium on photosynthesis of ZB-1 seedlings was the best,while the effect of 0.8 μM selenium on ZB-3seedlings was the best.4.Low concentration of selenium(0.2,0.4,0.8 μM)hydroponics for seedling growth phenomenon of non-toxic,Perilla varieties are promoting seedling activity of SOD,POD,CAT,reduce the content of MDA and O2·-and a high concentration of selenium(1.6,3.2,6.4 μM)hydroponic produces oxidative stress damage to seedling growth,reduction of seedling antioxidant enzyme activity and the content of MDA and O2·-up.5.Under the condition of hydroponics,low concentration of selenium(1,3,6 μM)in the leaves promoted the growth of seedling plants(stem and leaf)of two Perilla cultivars,but the root growth was not significant.The effects of leaf spraying with low concentration of selenium on photosynthesis,chlorophyll content,antioxidant enzyme activity,MDA and O2·-contents were the same as those of selenium hydroponic culture.Leaf spraying with high concentration of selenium(9,18 μM)significantly inhibited the growth of seedling plants(stem and leaf)of the two cultivars.High concentration of selenium inhibited photosynthesis,reduced chlorophyll content and caused oxidative stress damage to seedlings,resulting in reduced antioxidant enzyme activity and increased MDA and O2·-content.Selenium has dose effect on the germination of Perilla seeds and the growth and development of early seedling.Selenium at 10 μM concentration had a good effect on the germination and growth of Perilla seeds.In selenium hydroponics,the growth and development of Perilla seedlings were promoted by selenium at a concentration of 0.4~0.8 μM.When selenium was sprayed on the leaf surface,the selenium at the concentration of3~6 μM had a good effect on the growth and development of Perilla seedlings.Different ecotypes of Perilla cultivars have different sensitivity to selenium.ZB-1 is relatively sensitive to selenium.