Reduce Application Techniques Of Chemical Pesticides For Cotton Fields Along Dongting Lake Region

The article is aimed at gradually grave Dongting lake area environmental pollution current situation mainly, hope that the insect is cotton-padded, the mulch film covers by being put into use resisting, ways like plant source pesticide, decrease lake region chemical medicine uses amounts, preserve Dongting Lake area ecological environment, a synthetical study pass, reach result as follows1.But by the fact that the cotton field on the spot, observing, covering a film is compared with not to cover a cotton field, weed's happen having the obvious decrease, in the process of entire cotton growth, the film mulching cotton field has controlled weed's completely growth, block of wood epiphragma cotton field, amounts happened in weed reaching 13 or so per square metre, the peasant grows up in order controlling weed, in general employ 3 time of weed-killers, some have 4 time, the peasant household who there are still adopts the way weeding out artificially, this has been time-consuming taking a lot of work, has improved cost having already having contaminated an environment, Film mulching has a remarkable role therefore on the growth controlling weed,2.Occurrence and damage condition by the insect cotton cotton verticillium wilt having studied revolution of BT gene resists on inquiry in the field,have made clear that characteristic happened in the person, result indicates, Dongting Lake area covers the film cotton field verticillium wilt's difference is not big between happening resisting the insect cotton breed in diversity, but epiphragma and difference is not bigger between epiphragma.3.The main body of a book have compared cultivate resist the cotton-padded dynamic insect occurrence change around cotton field main vermin bollworm, cotton aphid, scale-like wing eye vermin etc., bears fruit indicate, not notable difference happened in film mulching with the cotton field not covering, to restraining a cotton aphid's; Some cover the film cotton breed, occurrence of the cotton aphid ratio no epiphragma's; Cover the film cotton field to boll worm and scale-like wing eye vermin but, are good than the restraint effect not covering. Therefore, we have decreased by the prevention and cure bollworm pesticide with scale-like wing eye vermin, the pesticide subtraction has executed the lessening not leading to output judging from final output, can cut down pesticide sigmatism under such premise being in guarantee output,this has provided a basis in order preserving lake region ecological environment4.The cotton aphid testing, discovering usage plant source pesticide 12 a-OH group derris ketone EC prevention and cure by field pesticide effect is very effective, being employing 7 Heaven's Queen, the effect reaches 90% the above, remaining effect to the aphid defending against expecting strong point, but because the plant source pesticide becomes effective slow, price insists to be taller than, large area spreads returning certain difficulty back to existence. The plant source pesticide is friendly to the environment, the ecological environment has importance therefore, to protection lake region but compared with tradition chemical medicine.