| Oxya chinensis is a major kind of pests in china, and it is widely distributed in most regions of our country. The major food of O. chinensis is rice, sorghum, maize, and other grasses. It has characters of reproducing and eating a large number of food, thus, it caused serious losses every year. O. chinensis likes humid condition. The color of its adult is yellow-green, and the female ones are bigger than the male ones. It has five stages in one generation. It live by the farmlands with little harm before the third nymph, while it begin to enter the farmland after third nymph, and cause great losses to the crops. The harm of it increased gradually with the flow of ages. As a agriculture-majored country, how to control the O. chinensis effectively is a problem we must solve in our rapid ecnomic development.Industrial production that includes chromium, mercury, lead, cadmium and arsenic into the environmental and lead to the pollution. Heavy metal was difficult to degradate through natural circulation in natural environment, so it may cause serious harm to the environment in a long period of time. When the chromium emissions of pollutants from wastewater of factory enter the farmland and other O. chinensis breeding ground, the heavy metal ions will invade the body of people through the food chain and cause a serious impact on people. For example, it will cause dermatitis on human body, and make the skin craze. Long-term contact with it will produce gastritis and stomach, even caused cancer to the biology.Heavy metals in insect digesting pathway mainly through metabolic processes. This paper with different concentrations of hexavalent chromium (Cr6+) solutions (0,7.5,15, and 30 mg/L) to cultivate wheat, which was to feed O. chinensis twice.1) Feed the O. chinensis form the 4th instar nymphs to adult. We determined the Cr contents in the wheat seedlings, the body and droppings of O. chinensis by flame atomic absorpting spectrometry. Discussion the relationship between the Cr contents in the wheat seedlings, the droppings of O. chinensis, the body of O. chinensis and the exposuring concentration. We found out the capacity of O. chinensis to regulation the Cr pollution in the envirment. Discovered that the relationship between the ability of O. chinensis to resist the Cr and the stage of O. chinensis.2) Feed the O. chinensis form the 1th instar nymphs to adult. Measure the weight and body length of male and female O. chinensis, we discovered the changing rules of the weight and body length with the enhance of Cr6+concent. This experiment discovery the impact of Cr6+to the growth of O. chinensis.3) Feed the O. chinensis form the 4th instar nymphs to adult. The O. chinensis was measured the superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activity and total antioxidant capacity (T-Aoc) through the Spectrophotometry. Discussion the relationship between the activity of important antioxidant enzymes and the total antioxidant capacity in the body of O. chinensis with the exposure of Cr6+ contents. Analyze the mechanism of various antioxidant enzymes in O. chinensis, when it is in the environment of excessive Cr contamination.Results of this study show that:1) In the first experiment of feeding O. chinensis, when we use different concentrations of Cr6+cultured wheat, the concentration of Cr in the wheat seedling showed a growing trend. The Cr which accumulated in the droppings of O. chinensis increased gradually with the increase of the Cr6+concentration. The O. chinensis has the ability to control the excess Cr in the body, and it can dischange a part of Cr concentration through digestion.In the second experiment of feed O. chinensis. The accumulating trend of Cr in the wheat seedlings was similar to the first experiment, and this argued the conclusion come from the first cultivation of wheat seedlings. In the condition of same stage and different treatment in concentration, the Cr concent accumlated in the body of O. chinensis showed growing trend, with the increasing of Cr6+exposed concent. In the control group, 7.5 mg/L,15 mg/L and 30 mg/L group, with the age increased, the Cr concent in the body of O. chinensis firstly increased and then decreased. This descriptied the capacity for accumulation of chromium in the O. chinensis have relationship with a certain age. In the control and 15 mg/L group, the accumated Cr concent is highist in the 3rd stage, while in the 7.5 mg/L and 30 mg/L group, the accumated Cr concent is highist in the 5rd stage. The Cr concent decreased in the adult of O. chinensis and this can explain that the ability to accumate the Cr is weaker in the adult age of O. chinensis.2) After chronic exposure by Cr6+, with the increased of Cr6+, the weight of male and female O. chinensis showed a gradual decreasing trend and this explain that Cr6+can affect O. chinensis normal development of weight. With the increased of Cr6+, the length of male and female O. chinensis showed a gradual decreasing trend and it shows that the exposure of chromium have effect on the length of O. chinensis.3) With the increasing of Cr6+contents, the activity of SOD remained almost unchanged, and this explain that SOD is not sensitive to the various peroxide caused by the Cr6+exposure. The activity of CAT, GPx and the T-Aoc firstly increased and then decreased with the increasing of Cr exposure. T-Aoc included CAT, and CAT, which play an important role in response to the peroxide caused by Cr6+in the body, but their ability to regulate have a certain limit. |
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