| In order to investigate the inductive resistance of insect feeding and mechanical damage treatment to Cabernet Sauvignon grape leaves and the behavioral response of Lygocoris(lugus)lucorum to different feeding and mechanical damage treatments,the secondary metabolites,nutrients and related metabolism of Cabernet Sauvignon grape leaves under different treatment methods and time were determined by biochemical method.The changes of enzyme metabolites content were measured by Y-tube method,and the effects of different treatments on the selection of Lygocoris(lugus)lucorum were determined,so as to explore the correlation between inducing factors and inducing resistance.The physiological defense mechanism of Cabernet Sauvignon under different stresses was analyzed to provide theoretical basis for the further use of information compounds to control Lygocoris(lugus)lucorum.The results are as follows:(1)Effects of insect feeding and mechanical damage on nutrient changes of Cabernet SauvignonBoth mechanical injury and feeding treatment could induce the change of plant nutrient content,and the induction effect of feeding injury was more significant,and the induction of protein induced by mechanical injury was delayed in expression time.The expression of amino acids increased first and then decreased.There were differences in the expression and expression time of metabolite in Cabernet Sauvignon leaves under feeding and mechanical damage.The induction effect of dietary treatment on amino acid and protein was increased,decreased and then increased,and there was no obvious regularity between the two treatments on the induction of sugars.(2)Effects of insect feeding and mechanical damage on secondary metabolites of Cabernet SauvignonThe content of flavonoids increased and then decreased at 1 d,3 d,5d and 7d after mechanical injury,and the content of flavonoid was significantly higher than that of control at 1d、3 d、7 d and 1 d、3 d、7 d after feeding,the content of flavonoid was significantly higher than that of control at 1 d、 3 d、7 d.Condensed tannin;The induction effect of the two treatments on tannin was similar,and both treatments could induce the increase of tannin content.The content of tannin was higher than that of insect feeding under the induction of mechanical loss for 3 d、5 d、and 7 d higher than that of control,which was lower than that of insect feeding.The induction of phenolics induced by mechanical injury showed a tendency of decreasing at first and then increasing,except that on the 1st day,it was lower than that of the control,and then it was higher than that of the control.The contents of phenolics induced by feeding injury increased significantly in 1d-7d,showing an increasing trend.(3)Effects of insect feeding and mechanical damage on metabolic enzymes in Cabernet Sauvignon grapeThe effect of inducing enzyme activity of Cabernet Sauvignon grape leaves in two ways was obvious,and the effect of different treatment time was different.The effect of mechanical injury on trypsin inhibitor increased first and then decreased,which was higher on the 1st day,3rd day,lower than that of the control on the 1st day,3rd day,5th day and 7th day,while after feeding,the trypsin inhibitor showed a continuous increasing trend.There was no obvious change in trypsin inhibitor induced by the two methods on the 1st day,but decreased after the 3rd day.On the 3rd day,the enzyme activity reached the maximum value.The induction of PPO induced by mechanical injury showed an irregular fluctuating trend,reaching significant difference at 5 days and 7 days,and the activity of PPO induced by feeding stimulation reached the maximum on the third day,reaching a significant difference.The activity of SOD induced by mechanical injury was lower than that of control and feeding stimulation at 1 d,5 d,7 d,only the activity of 3 d was higher than that of control and feeding injury.(4)Effects of insect feeding and mechanical damage on other substances in Cabernet Sauvignon grapeThe chlorophyll content of Cabernet Sauvignon grape leaves treated by mechanical injury and Lygocoris(lugus)lucorum feeding was lower than that of the control group in four time periods,and the induction effect of insect feeding was more obvious than that of the control group,except on the 1st day,it was lower than that of the mechanical injury.Both methods result in a decrease in chlorophyll content.The contents of MDA in leaves of Cabernet Sauvignon were also decreased to some extent after being stimulated by the two methods,which were similar to those of chlorophyll in the leaves of Cabernet Sauvignon.Except that the mechanical injury was slightly higher than that of the control on the 3rd day,the other time periods were lower than that of the control,but there was a difference in the amount of MDA response induced by the two methods.(5)Study on effect of insect resistanceIn the natural state,Cabbage Sauvignon has a strong inducement effect on Lygocoris(lugus)lucorum.In a short period of time,Cabernet Sauvignon,which is damaged by insects,has an inducing effect on Lygocoris(lugus)lucorum,and when the hazard exceeds a certain amount of time,it tends to choose air or CK;In the combination of mechanical injury plants,there was no obvious choice of behavior in the first 2d treatment.The results show that both insect feeding and mechanically damaged plants will produce some repellent volatiles,which will lead to food rejection effect.In a short period of time,the plant taken by insects has an inducing effect on Lygocoris(lugus)lucorum,which is different from mechanical damage.The longevity of Lygocoris(lugus)lucorum fed on treated Cabernet Sauvignon grapes was significantly shortened,suggesting that the induced Cabernet Sauvignon produced resistant substances.The results showed that the two kinds of induction methods can induce the insect-resistance of the plant,but there is a difference in the expression and the expression time.The induced Cabernet Sauvignon has a distinct repellent effect on Lygocoris(lugus)lucorum,and has an effect on its life activity. |
