Effects Of Two Inducing Agents On Growth And Disease Resistance Of Tomato Seedlings

Under the low temperature and low light environment of the greenhouse in the northeast cold region,many diseases such as gray mold in tomato production are serious,which seriously affects the yield,quality and income of tomato.Planting improvement,disease prediction and chemical control have been widely used in tomato disease control,but the most economical and environmentally friendly disease prevention and control methods are still increasing the resistance of the tomato host itself.In recent years,plant disease resistance inducers have great potential for application in the safe production of facility tomatoes due to their broad spectrum,effective,safe drug use and environmental pollution.In this experiment,two commercially available plant immune inducers（Albit and Jingdusha）were selected,and potted artificial inoculation method was used to study the effects of these two kinds of inducers on the resistance of tomato seedlings to gray mold.Good induction concentration,application interval,number of administrations and induction duration,etc.,to determine the inducing disease resistance effect and application technique of Albit and Jingdusha in tomato;meanwhile,preliminary study on the growth of tomato seedlings by these two kinds of inducers The effects of physiological and biochemical characteristics were explored to explore the possible mechanism of action,in order to provide a basis for the application of the inducer to the tomato production in the greenhouse in Northeast China.The main results are as follows:（1）The tomato"Liaoyuanduoli"was used as a test material to study the disease resistance of Albit and Jingdusha to induce tomato seedlings against gray mold.The results showed that both Albit and Jingdusha inducing treatment could significantly increase the resistance of tomato seedlings to gray mold;the induced concentration of Albit was 0.15mL·L^-1,the interval was 5 days,and the induction was 2 times.When the control effect on tomato gray mold can be as high as 62.11%;the concentration of 1.0 mL·L^-11 is continuously induced twice,and the induction interval is 5 days,the relative control effect on tomato gray mold can be as high as 61.82%.（2）The application of Albit has a significant effect on the growth,physiological and biochemical characteristics of tomato seedlings.After applying Albit to tomato seedlings,the plant height,stem diameter,root length and leaf dry weight and fresh weight increased to some extent.The net photosynthetic rate of tomato leaves increased significantly,and its effect lasted for 72 hours.Chlorophyll of tomato leaves The content increased significantly at12-144h,but the stomatal conductance,intercellular CO₂ concentration and transpiration rate only increased to some extent after 12h induction;the soluble sugar content of tomato leaves was lower than 12-72h after Albit induction.Control,but significantly higher than the control at 144h;soluble protein in tomato leaves increased significantly at 12h after Albit induction,and then decreased significantly;meanwhile,DAB and NBT staining results showed that tomato after 12-48h after Albit spray treatment Significant accumulation of H₂O₂ and O₂^-.in leaves of seedlings may make tomato seedlings more resistant to disease.（3）The treatment of jingdusha sorghum can significantly affect the growth and physiological and biochemical characteristics of tomato seedlings.After induction treatment,the plant height,stem diameter,root length and leaf dry weight and fresh weight of tomato seedlings increased significantly.jingdusha photosynthetic rate,stomatal conductance,intercellular CO₂ concentration,transpiration rate,The chlorophyll content increased significantly at 12 h after induction;the soluble sugar content of tomato leaves decreased first and then increased,and the soluble protein content of tomato leaves increased first and then decreased;At 12-48h,O₂^-.and H₂O₂ in tomato leaves were significantly deposited in tomato leaves,which was helpful to enhance the stress resistance of tomato seedlings.