The Screening Of Mixed Synergist To Three Insecticides Against

Following the development of human scientific techniques,chemical pesticides will confront with the ecological and environmental pressures. Pesticides is one of the most important origins for environmental pollution. As chemical pesticides is widely used,the number of natural enemies goes down so quikly that the number of insects goes up rapidly again as it's out of controlling. On the other side, the fastness of insects will go stronger if continuously using one kind of pesticides or analog. Farmers have to increase the dosage of the pesticides to ensure the effectiveness. If this exists for a long time, malignant circulation will appear. the effectiveness of the pesticides can be improved, the fastness of the insects can be delayed and the environmental pollution can be reduced by using synergists. However,the national researches on synergists begin very lately,and there are few institution centers in China. The variety of synergists is so rare and the effectiveness isn't so satisfied that it restricts the widely using of the synergists. During recent years,there are many reports about the researches on synergists, and many products come to the market. But most researches focus on the introductions of how to use single and the development of synthesis methods, and there is no report about mixed synergists.As above situation is existed, this experiment hammers at the effectiveness of the mixture of several single synergists, and hoping that better effectiveness of mixed synergists can be found.The steps of this experiment can be generalized as the follows. Firstly, eight representative single synergists will be choosed. Secondly, determine three single synergists which are have good effectiveness for all pesticides, to make mixed synergistsIn hope that the best mixed synergist which contain two or three single synergists.1 the toxicity mensuration of eight kinds synergistsThe result of eight synergists to Lipaphis eysimi show that the mortalities are under 15%, which is normal. Meanwhile, all the synergists are almost non-toxicity, it's fit for the condition that synergist is non-toxicity, so all the synergists can been applied in this experiment2 the riddling of the best synergistThe riddling result of the best synergist showed that to imidacloprid the first fourth synergist are TTP,PEG,NT,T-20; to beta-cypermethrin first fourth synergist are T-20,PEG,NT,Neem Oil;to acephate first fourth synergist are T-20,PBO,PEG,NT.From above results we can see that PBO and TTP are good for increasing the toxicity of imidacloprid,but isn't fit for acephate.Compared with others synergists NT,PEG and T-20 are good for increasing the toxicities of all pesticides.So in this experiment NT,PEG,T-20 be prepared for the next step3 the riddling of the best mixed synergist which contains two synergistsFirst mixing NT,PEG and T-20 each other in the proportion of (3:1,2 :1,1 :1,1: 2,1:3 ) then mixing the blend and pesticide in the proportion of 1 : 5 last measuring the toxicities the experiment result show that the best mixed synergist to imidacloprid is made up of PEG and NT in the proportion of 1:2;to beta-cypermethrin is made up of PEG and T-20 in the proportion of 1: 2;to acephate is made up of T-20 and NT in the proportion of 1 :14 study about the mixed synergist which contains three synergistsWhat's the proportion of single synergist in the mixed synergist which contains three synergists based on the riddling of the best mixture-synergist which contains two synergists and the account. finally ,decided three different proportions (PEG : NT : T-20=1:2: 2,1:2:6,3 : 2: 6) in this experiment Blend three mixed synergists and pesticides last measuring the toxicities the experiment result show that the mixed synergist in the proportion of 1: 2: 2 is the best one that fit for imidacloprid and beta-cypermethrin, at the same time, it is also fit for acephate,the SR is high to 28.2569,is second only to The result of above show that the mixed synergist in the proportion of 1: 2: 2 is which one we need Because it's better than any other single synergists or mixed synergists...