Effects Of Seed Coating And Amino Acid Spraying On Maize Resistance And Yield Under Low Temperature Stress

Maize is a warm-loving crop,which requires high temperature in actual production and planting process.Low temperature stress is a common abiotic stress during spring maize planting in northeast China,which severely limits maize yield.Amino acid foliar fertilizer and seed dressing agent are common plant growth regulators which have positive effects on increasing plant stress resistance and yield.In this study,The maize variety'Zhengdan 958'was used to explore the effects of leaf spraying of amino acid and compound application of amino acid and seed coat agent on maize cold resistance and yield under low temperature stress,so as to provide basis for maize disaster reduction and prevention.The results of this study are as follows:1.The growth and photosynthesis of maize seedlings were inhibited when treated with low temperature stress By amino acid spraying treatment can effectively alleviate the low temperature of the seedlings of corn plant height,stem diameter,leaf area,fresh weight and leaf water content,significantly promoted the seedling growth,relieve the inhibition of low temperature on maize photosynthetic system,improve the seedling SPAD value,Improve the photosynthetic capacity of maize.2.The activities of POD,CAT and SOD of maize treated by amino acid spraying and the combination of amino acid spraying and seed coating agent were significantly higher than those of the control,and the scavenging ability of reactive oxygen species and cold resistance were significantly improved.The MDA content and REC value of seedlings were significantly decreased by spraying amino acid and compound treatment of amino acid and seed coat agent,and the cell membrane was effectively protected from peroxidation.The results showed that CDA-COLD treatment could improve the activity of antioxidant enzyme and protect cell membrane of maize.3.Compared with COLD group,the soluble sugar content and soluble protein content of maize were significantly increased by 36.35%and 65.63%,respectively,after amino acid spraying or amino acid+spermatozoonil and fluromonil seed coat compound treatment,which accelerated the accumulation of osmotic regulatory substances.The synergistic effect of amino acid+seed coat compound treatment is more obvious.4.Staining with DAB,NBT and Trypan blue,we found that low cold stress would lead to the accumulation of H₂O₂ and O^2-contents in maize leaf cells,and the number of brown and blue spots increased.The treatment of amino acid spraying,amino acid spraying and the combination treatment of spermidonil and roflonil seed coating agent effectively reduced the damage of cells caused by low temperature,and the number of spots decreased.The results showed that the effect of CDA-COLD treatment group was more obvious.5.Compared with COLD group,ear length,ear diameter,grains per ear and 100-grain weight were significantly improved after amino acid spraying and compound treatment of amino acid and seed dressing agent,alleviating the damage of ear caused by low temperature.The ear weight and grain weight of maize were significantly increased,the grain water content was significantly decreased,and the harvest quality was improved.Compared with COLD,the yield of A-cold and CDA-COLD increased by 9.93%and 13.90%respectively,indicating that the treated maize showed good COLD resistance and the yield increased significantly.Among them,CDA-COLD treatment group had better effect on increasing maize yield at low temperature.In conclusion,seed dressing agent treatment and foliar spraying of amino acids can effectively alleviate low temperature stress and promote maize yield.