| The paper studied the changes of the growth idexs, quality idexs and carbon andnitrogen metabolism in cruciferous vegetable Brassica campestris ssp.chinensis(L.)under chemical pesticide(cyhalothrin and carbosulfan)and botanical pesticide(azadirachtin) stress from the pesticide-cruciferous vegetable-striped flea beetle(SFB), phyllotreto striolata (Fabricius) system of view, which could lead responseof SFB's acetylcholinesterase, carboxylesterase, glutathione-s-transferases, foragingand survival.The results were as follows:1 Effects of pesticides on the growth idexs of Brassica campestris ssp.chinensis(L.)The research showed that in different days of applicating of pesticides, plant height of cyhalothrin treatment had not significant difference from that of control, and was higher than that of control which promoted the growing of Brassica campestris ssp.chinensis(L.), but that of carbosulfan and azadirachtin treatments were just on the contrary; the bleeding liquid contents of three pesticides treatments were basically lower than that of control, and this indicated the bleeding liquid contents of plant decreased under pesticides stress, of which the effect of cyhalothrin was the most significant during after applicating pesticides from 2d to 5d; under three pesticides stress, the contents of chlorophyll a, chlorophyll b and total chlorophyll had significant changes during after applicating of pesticides from 4d to 10d, and the effects of pesticides on the chlorophyll were basically forward, of which the chlorophyll a content of cyhalothrin treatment was higher 20.70% than that of control in 4d after applicating of pesticides; the chlorophyll b content of cyhalothrin treatment was higher 71.13% than that of control in 10d after applicating of pesticides.2 Effects of pesticides on the quality idexs of Brassica campestris ssp.chinensis(L.)The research founded effect of the three pesticides on the ascorbic acid content of Brassica campestris ssp.chinensis(L.) was very complex, and the effect tendency were high-low cross state, of which the difference between that of cyhalothrin treatment and that of control was small, but the ascorbic acid content of cyhalothrin treatment was higher than that of control after applicating of pesticides from 1d to 7d, especially was 185.5mg/100g and was higher 84.88% than that of control in 4d after applicating of pesticides, so this showed effect of cyhalothrin on the ascorbic acid of Brassica campestris ssp.chinensis(L.) was forward; but effect of three pesticides on the soluble protain of Brassica campestris ssp.chinensis(L.) was negative, espacilly the soluble content of cyhalothrin treatment was lower 11.15%than that of control. 3 Effects of pesticides on the carbon and nitrogen metabolism in Brassica campestris ssp.chinensis(L.)During the applicating of pesticides times, the reducing sugar contents of cyhalothrin treatment and carbosulfan treatment were slightly lower than that of control, but that of azadirachtin treatment was slightly higher than that of control; effect of three pesticides on the sucrose in Brassica campestris ssp.chinensis(L.) was negative, especially the descending percentage of the reducing sugar contents of three pesticides treatments compared to that of control were 43.12%(azadirachtin)>20.08% (carbosulfan) >16.56% (cyhalothrin) , of which the difference of between the reducing sugar contents of cyhalothrin treatment, carbosulfan treatment and azadirachtin treatment was very significant(p<0.01); effect of cyhalothrin and carbosulfan on the total soluble sugar in Brassica campestris ssp.chinensis(L.) was negative, too, especially that of carbosulfan treatment was significant, but that of azadirachtin treatment was on the contrary. Effect of three pesticides on the free amnio acids in Brassica campestris ssp.chinensis(L.) was basically forward, and the total amnio acids contents of cyhalothrin treatment and carbosulfan treatment were higher 12.83% and 13.88% than that of control respectively, and the difference of between that of the two pesticides treatments and control was very significant (p <0.01) , but the difference of the contents of Asp, Thr, Ser, Glu, Gly, Ala, Cys2 and Leu in different treatments was also very significant(p<0.01); the essential amino acids of human in different treatments were all higher than the model spectrum standard value excpt that of sulfur amino acid; with the growth of Brassica campestris ssp.chinensis(L.), the changing tendency of the essential amino acids of insect in different treatments rised first and descended later, of which Leu content and Lys content were the highest of all the essential amino acids of insect, and accouted about 9%of the total amino acids content respectively, but Met content was the lowest, only accuted about 0.3% of the total amino acids content.4.The changes of SFB's survival,foraging and enzymes after feeding Brassica campestris ssp.chinensis(L.) with applicating pesticidesThe research results showed SFB's survival rate and foraging amount decreased significantly in early days after applicating pesticides, of which SFB's survival rate and foraging amount of carbosulfan treatment was only 39.39%and 17.03 mm~2/30SFBs respectively in 0d after applicating pesticides, and foraging amount was lowed 136.1mm~2/30SFBs than that of control, but SFB had no death in3d after applicating pesticides.The activity of SFB's acetylcholinesterase and glutathione s-transferases were both higher than that of control, especially the acetylcholinesterase activity of azadirachtin treatment was 1.67times of that of control in 7d after applicating pesticides, and had very significant difference from that of control (p<0.01), but the difference of effect of three pesticides on the glutathione s-transferases activity compared to that of control was not significant.Addtionally, the three pesticides all inhabited the carboxylesterase activity.
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