Study On Physiological Effects Induced By Soybean Peptide On Heat Resistance In Banana Seedlings

Banana is one of important economic crops in the world, it is also one of the staple fruit in southern China. Banana is originating in Southeast Asia, the optimum temperature for growth at between 24℃-32℃As the "greenhouse" effect, rising global temperatures, but the current high-temperature physiology of small banana. Soybean peptide is a soy protein was hydrolyzed by 3 to 6 amino acid peptide mixture of low, there are many peptides in the application of plant yield, better quality reports. This study was designed to study high temperature stress at the physiological and biochemical changes of banana seedlings and banana soy peptides induced heat tolerance mechanisms, banana seedlings to clarify the mechanism of resistance to high temperature and improve the quality of banana, the banana industry to promote the efficient development of theory.The study was conducted with Brazil banana seedlings which is one of varieties grown in China, first, pretreatment on banana leaves, then move into climate-control chest imitating high temperature stress,study of soybean peptide in banana seedlings under high temperature stress on physiological effects,from selected high concentration of soybean peptide. The results were as follows:(1) High temperature stress inhibited the growth of banana seedlings of leaf area,35℃/20℃(day/night) treatment showed excessive growth phenomenon; crown fresh weight and dry weight, root fresh weight and root dry weight decreased by inhibition and proportional decrease in intensity with stress.0.6% soybean peptides by pretreatment of banana seedlings, the highest fresh weight, root fresh weight and shoot dry weight, root dry weight, the largest increase over the previous year. Heat stress, the suitable concentration of soybean peptide treatment to seedlings in the morphology showed significant advantage.(2) Under high temperature stress to promote banana seedlings, the net photosynthetic rate, leaf relative water content and total chlorophyll decreased, the suitable concentration of soybean peptide pretreatment to maintain a range of high temperature stress on Leaf net photosynthetic rate, thereby enhancing seedling heat resistance.(3) At 42℃high temperature stress within 24 h, the suitable concentration of soybean peptide pretreatment can improve the Pro content in banana leaves, soluble protein and soluble sugar content and lower leaf MDA content and electrolyte leakage, while increasing SOD, POD and CAT activity, slowing the production rate of superoxide anion, thus improving the heat resistance of banana seedlings.(4) Different concentrations of soybean peptides to improve heat tolerance of banana seedlings are very different, the best concentration of 0.6%.