DC-EPG analysis on effect of tea plant induced by methyl salicylate against feeding of tea green leafhopper

Miao Jin Han Baoyu(Tea Research Institute,Chinese Academy of Agricultural Sciences,Hangzhou310008,Zhejiang Province,China)

video-direct current-electrical penetration graphy;methyl salicylate;tea green leafhopper;tea seedling;induced resistance

After tea seedlings were induced by methyl salicylate(MeSA) which had been slowly emitted for 24h or 48h,tea green leafhoppers of the third instar were introduced on the tea seedlings.The video-direct current-electrical penetration graphy was used to record the various waveforms formed by the tested leafhoppers for 3h.Seven distinct types of waveforms were recognized,based on which fifteen EPG parameters,describing the feeding behaviour of the leafhopper,were determined,and used to evaluate the resistance of tea seedlings against leafhoppers.Compared with pierce-sucking behaviour of the leafhopper on non-induced tea seedlings(CK),the probing number on 0.2,0.4 and 0.8mmol/L MeSA induced tea seedlings increased,which was respectively 8.30±1.13,13.25±3.95,15.01±2.68 and 34.50±7.56;accordingly,the non-feeding probing time was 110.97±5.2min,128.39±6.76min,148.35±6.14min and 131.94±10.75min;and the accumulative duration of the phloem phase was evidently shortened,i.e.,52.90±2.22min,9.08±2.6min,8.87±1.44min and 15.89±2.21min.The induction effect by 0.4mmol/L was most obviously among the three treatment dosages.The effect induced for 24h was stronger than that induced for 48h.It should be considered that the dainty degree of the tea seedling to the leafhopper deteriorates after they are induced by MeSA,to a certain extent,the resistance of tea plants against the leafhopper is induced.