| The study of functional film used in establishment growth and safe production of vegetable were attented by people in recent years, At present, reasonable selecting film, scientific using pesticide according to kinds of vegetable have been hotspots of research, because which can increase yield, improve quantity and reduce pollution of vegetable product. Therefor, the experiment studied on the effect of temperature and light of light conversion film and the effect on growth, yield and quality of different kinds of vegetable, analyzed the accumulation and degradation dynamics of pesticides in vegetables, ensured the security of different pesticides. The purpose of experiment was to afford theoretically reference to popularization of light conversion film and reasonable selecting of pesticide. The mostly results were as follows:1. The results indicated, the proportion of 400~500 nm blue-purple light and 600~700 nm red-orange light of light conversion film was respectively increased by 13.37% and 16.68%. Because the two best strong spectrum areas of chlorophyllo were covered with the spectrum ranges, so the better proportion was propitious to chlorophyllo absorbability of light energy. Besides the light conversion film had the effect of adjusting temperature. When temperature was lower, the air temperature and ground temperature under 5 cm in light conversion film were respectively improved by 0.5~0.8℃and 0.3~0.6℃, but when temperature was more high, they were lower than CK. 2. Vegetables growth in light conversion film were stronger than CK, at the same time overground and underground fresh weight were increased. In harvest time, the yield of spinach, carrot, green soy bean in light conversion film were respectively increased by 13.79%, 11.87% and 9.13%, the nitrate content of vegetables in light conversion film was reduced, but the contents of dry matter, soluble glair and Vc were increased, so the quality of vegetable was improved remarkable.3. The change of light quality in light conversion film induced to the proportion promotion of blue-purple light and red-orange light in transmission spectrum, and increase of photic pigment content, as a result, the photosynthesis speed of spinach in light conversion film was improved. At the same time, The change of light quality affected the activity of antioxidant enzymes, strengthened the activity of protective enzymes in leaves, so the activity of SOD, POD, CAT enzymes were respectively improved by 27.11%, 25.85% and 18.52% in harvest time. However the content of MDA was lower than CK, it's maximum was 0.29μmol·g-1FW, which was reduced by 25.64%; the electrolytic leakage in cell had the same change trend, which was related with more high activity of SOD, POD and CAT, because they were in favor of cleaning out the membranous peroxide.4. After pesticide sprayed in field, the pesticide residues in vegetables were reduced gradually along with time. But pesticides had different effect on vegetables, the residues of Methamidophos, Chlorpyrifos, Cypermethrin were reduced successively. Moreover the residues in different organs were also different, the residue of roots, leaves, stems and legumen was reduced successively. The half life of pesticides in vegetables were also different, The half life of Cypermethrin was longer than Methamidophos and Chlorpyrifos, but difference of the latter was small, for example the half lifes of Methamidophos, Chlorpyrifos, Cypermethrin in spinach root were 6.8, 6.5 and 7.8 d, which in carrot were 8.4, 8.0 and 8.9 d. When vegetables were harvested, the residues of pesticides in carrot, spinach, green soy bean were reduced successively, the residues of Cypermethrin in them were 0.05, 0.02, and 0 mg/kg respectively, which were all under MRL, the residues of Chlorpyrifos were over MRL, except in legumen, but the residues of Methamidophos in vegetables were all over MRL, so it couldn't be used in safe production of vegetable.5. There are significantly difference in pollution of vegetables after pesticide sprayed on leaves. When Methamidophos, Chlorpyrifos and Cypermethrin were sprayed on leaves at 1:1000 dilution ratio, there were evidently difference in different organs, the residue in leaves was higher than in roots. In harvest time the residues of Methamidophos, Chlorpyrifos and Cypermethrin in spinach were 0.02, 0.01 and 0.01 mg/kg respectively, which in carrot were 0.01 mg/kg, 0 and 0 mg/kg respectively, but the residue in green soy bean were 0.01, 0.01, and 0 mg/kg. Besides the residue was correlated positively with sprayed time spaced with harvest time, moreover the residue increased along with concentration.6. The soil was polluted by the pesticide sprayed in field and on leaves, moreover the pollution of pesticides was different, in which the pollution of Methamidophos, Chlorpyrifos and Cypermethrin were mitigated successively. When pesticides were sprayed in field, the residue in soil was reduced gradually, in prophase the reduced speed was rapider than in anaphase, 90 days later, the residue of Methamidophos, Chlorpyrifos and Cypermethrin were 0.27, 0.21 and 0.07 mg/kg respectively, their degradable rate were 97.1%,97.6% and 94.4% respectively, it is obvious that the speed of Methamidophos and Chlorpyrifos were quicker than Cypermethrin, the half life of them were 23.5, 22.9 and 25.4 d respectively, which had the same difference.
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