Screening And Validation Of The Material Combination To Alleviate The Injury Of Strawberry Seedlings At Low Temperature

Strawberry?Fragaria×ananassa?belongs to Rosaceae?Rosaceae?Strawberry?Frag aria?perennial herb berry,which is the largest tree species planted in the fruit tree pr otection area at present.In this study,the strawberry variety"Zhangji"?Fragaria×anan assa cv.Toyonaka?was used as experimental material.In low temperature environment?day 4±0.5?;night 0±0.5??,the orthogonal composition of NaHS,Na₂SeO₃,glyceri n?C₃H₈O₃?and amino acid water-soluble fertilizer was used to spray strawberry seedli ngs.The chilling injury index,relative conductivity,MDA content,antioxidant enzyme activity and photosynthetic performance of strawberry seedlings were investigated The final optimal treatment combination is selected by comparing the optimal treatment c-ombination with the theoretical one.The main results are as follows:?1?The tested combinations of sodium sulfide,sodium selenite,glycerol,and amin o acid water-soluble fertilizers all improved the cold resistance of strawberry seedlings to a certain extent.?2?The best test combination to reduce the cold damage index is A2B2C3D1?sod ium selenite 5 mg/L+sodium sulfide 80 mg/L+glycerol 5 ml/L+amino acid water-soluble fertilizer 20 mg/L?;the influence of each factor of the cold damage index is large In order,sodium sulfide>sodium selenite>glycerin>amino acid water-soluble fertilizer.The theoretical optimal combination is A1B2C2D3?sodium selenite 2.5 mg/L+sodium sulfide 80 mg/L+glycerin 3 ml/L+amino acid water-soluble fertilizer60 mg/L?.?3?The best test combination to reduce leaf cell membrane permeability at low te mperature was A2B2C3D1.The influence of various factors of the relative conductivi ty is in the order of sodium sulfide>glycerol>amino acid water-soluble fertilizer>so dium selenite.The theoretically optimal combination is A1B2C2D1?sodium selenite 2.5 mg/L+sodium sulfide 80 mg/L+Glycerol 3 ml/L+amino acid water-soluble ferti lizer 20 mg/L?.?4?The best test combination to reduce the MDA content of leaves at low temper ature is A2B2C3D1;the effect of each factor of the MDA content is in order from sodium sulfide>glycerol>sodium selenite>amino acid water and fertilizer.Sodium s elenate 5 mg/L+sodium thiohydride 40 mg/L+glycerol 5 ml/L+amino acid water-soluble fertilizer 20 mg/L).?5?The best experimental combination of maintaining photosynthetic performance o f leaves at low temperature is A2B2C3D1;the effect of each factor of the chlorophy ll content is in the order of sodium sulfide>glycerol>sodium selenite>amino acid w ater-soluble fertilizer.The theoretical optimal combination A1B1C2D1?selenium?.S odium 2.5 mg/L+sodium thiohydride 40 mg/L+glycerol 3 ml/L+amino acid wate r-soluble fertilizer 20 mg/L).?6?The experimental combination of the best comprehensive effect is A2B2C3D1,and the theoretical combination of the best comprehensive effect is A1B1C2D1.The comparison shows that the best combination to improve the cold resistance of strawber ry seedlings are the experimental combination A2B2C3D1.