Effects of Exogenous ABA on Cold Resistance and Tender Seedlings Growth of Winter Wheat Dongnongdongmai 1 in Cold Area

Dongnongdongmai 1 is the only winter wheat(Triticum aestivum L.) cultivar that can bear low temperature and grow normally in Heilongjiang province.This experiment used this material to investigate the effects of exogenous ABA on cold resistance as the material by adding with ABA(concentrations were 0,10-4、10-5、10-6、10-7mol/L)in the agar medium(3%) in dark(Temperature 2~4℃,training boxes tilt angle of 45°),then were investigated after 11 days.The results show that: ABA has significant impacts on cold resistance,the low concentration of ABA can increase the growth of wheat under low temperature,the high concentrations inhibit growth.For increasing the wheat cold resistance,the optimal concentration of ABA is 10-7mol/L.Treating the wheat seedlings in ABA optimal concentration(10-7mol/L)(leaves and roots spraying both) in the low temperature.Five days later,several physiological indicators related with the cold resistance were tested,the results showed that: seedling at cold temperatmes,the ABA can increase chlorophyll content,soluble sugar content and soluble protein content,improve the activity of SOD and decrease membrane permeability;the effects of root absorption is better than that of leaf-spraying.