Effects of Seed Coating Treatment on Seed Germination,Seedling Growth and Physiological Characteristics of Peanut at Low Temperature
Peanut is susceptible to low temperature stress during sowing stage.In order to clarify the effect of seed coating treatment on seed germination,seedling growth and physiological characteristics of pea-nut under low temperature stress,the normal temperature(25 ℃)treatment was used as the control(CK),two low temperature stress treatments of 8 ℃ and 10 ℃ were set,and seed coating and water wetting were set under each temperature.The effects of seed coating treatment on seed vigor,dry matter accumulation,root morphological characteristics and photosynthetic physiology of peanut under low temperature stress were studied.The results showed that compared with the normal temperature treatment,the low temperature stress at 8 ℃ significantly reduced the germination energy(5.9％),germination percentage(7.7％),germi-nation index(11.0％),seed vitality index(6.9％),and the SPAD value of seedling(11.4％).At the same time,low temperature stress at 8 ℃ inhibited the growth of seedling root system,the root length,root sur-face area and root volume were significantly reduced by 50.0％～50.2％,44.9％～48.1％and 48.2％～48.5％,respectively,compared with those under normal temperature and low temperature stress at 10 ℃.However,low temperature stress at 8 ℃ had no significant effects on the dry matter accumulation,maximum photochemical efficiency,intercellular carbon dioxide concentration,stomatal conductance,net photosynthetic rate and transpiration rate of peanut seedlings.Seed coating treatment significantly increased germination energy(8.2％),seed vitality index(10.9％),root length(45.1％)and root surface area(38.4％)of peanut seedlings under low temperature stress at 8 ℃,but had no significant effect on these physiological characteristics under low temperature stress at 10 ℃ and normal tempera-ture treatments.Mean while,seed coating treatment also significantly improved the dry matter accu-mulation,maximum photochemical efficiency and photosynthetic characteristics of functional leaves of peanut seedlings under normal temperature treatment,and the dry matter accumulation of above ground and maximum photochemical efficiency under low temperature stress at 10 ℃,but had no sig-nificant effect on these characteristics under low temperature stress at 8 ℃.In conclusion,peanut seed germination and seedling root growth responded more significantly to low temperature stress,while seed coating treatment alleviated low temperature stress by resume the above indicators,and im-proved dry matter accumulation and photosynthetic physiology of peanut seedling under mild low tem-perature stress and normal temperature treatment.
low temperature stressseed germinationpeanut seedlingroot morphologyphoto-synthetic physiology
万方数据
维普
