| Wolfberry is one of the economic and ecological species which extensive cultivated in northwest China. Aphis is one of the most seriouse pests in wolfberry cultivation area and causese a great economic losses to wolfberry. Chemical pesticides has been use to control aphis in recent years, but it has caused the resistance of the aphis and the fruit pollution. It has also caused the decrease in fruit quality and the export of wolfberry. It has reducesed the value of the wolfberry as a herbal and health product. In order to explore new control methods, the induced resistance of wolfberry by jasmonic acid and aphis was studied. The secondary compounds, primary substance, enzyme activity of wolfberry and behavioral responses of aphis and Chilocorus rubidus Hope were studied .The main contents as followed:1. The contents of foliage flavone and tannin in leaves of wolfberry increased significantly after jasmonic acid induced and damaged by the aphis. 0.1mmol/L jasmonic acid had induced the distinct increase of flavone and tannin contents, the maximum amplitude appeared on the 5th day post the treatment. The contents of foliage flavone and tannin separately increased 1.34 and 1.36 folds post the treatment. In addition, the contents of foliage flavone and tannin of wolfberry increased significantly after the aphis damaging and the maximum appeared on the 1st day. The contents of foliage flavone and tannin increased 1.34 and 1.28 folds post the damaging, respectively.2. The contents of foliage protein and soluble sugar in wolfberry leaves decreased significantly after jasmonic acid treatment and aphis damage. 0.001mmol/L jasmonic acid treatment induced the distinct decrease on the contents of protein especially on the 7th day post the treatment and it was decreased by 34.9%. 0.1mmol/L jasmonic acid treatment induced the contents of soluble sugar dropped rapidly and the minimum appeared on the 1st day. It was decreased by 13.6%. In addition, the contents of foliage protein and soluble sugar in leaves of wolfberry decreased significantly after aphis damaging and the minimum appeared on the 1st day. The contents of protein and soluble sugar separately decreased by 30.8% and 16.7% post the aphis damage.3. The activities of polyphenol oxidase (PPO) and peroxidase (POD) in leaves of wolfberry increased significantly after jasmonic acid treatment and damaged by aphis. 0.1mmol/L jasmonic acid treatment induced the strongest response of PPO and the maximum amplitude appeared on the 3rd day. 0.01mmol/L jasmonic acid treatment induced the strongest response on the activities of POD and the maximum appeared on the 7th day. The maximum activities of PPO appeared in the 7th day and the maximum activities of POD appeared in the 5th day after damaged by aphis.4. The activities of PPO and POD in leaves of wolfberry increased after jasmonic acid treatment and damaged by aphis. The isoenzymes are analyzed by PAGE and the results showed that new isozyme bands were induced by 0.1mmol/L jasmonic acid treatment.5. Effects of jasmonic acid treatment on the development and fecundity of aphis. The results showed that the developmental duration, adult longevity, fecundity and aphis weight were significantly influenced by jasmonic acid treatment of wolfberry and the influence related with the concentration of jasmonic acid. The longest nymph period fecundity was reduced significantly by jasmonic acid treatment and the higher concentration, the less fecundity. The fecundity was 19 nymph less than that of control at the concentration of 0.1mmol/L of jasmonic acid. The adult longevity was about 3 days shorter than that of control. The aphis daily weight was influenced significantly afterwards the third day. The 5th day aphis body weight difference between jasmonic acid treatment and control was 0.128-0.184mg.6. Behavioral responses of aphis and Chilocorus rubidus Hope to volatiles from wolfberry. The results showed that the volatiles from wolfberry had a definite repelled effect on aphis after jasmonic acid treatment, but had attracted on Chilocorus rubidus Hope after jasmonic acid treatment. When the wolfberry was damaged by aphis the volatiles from wolfberry didn't have significant effects on aphis and Chilocorus rubidus Hope. The volatiles from wolfberry-aphis complex had a visible attractive effect on Chilocorus rubidus Hope...
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