www.public4you.fora.pl

90nike5657fv

_1342
Why do not insect-resistant Bt cotton?

Body analysis. First,[link widoczny dla zalogowanych], what insect resistant cotton? Is not all cotton pest resistance, current, resistance is mainly to promote the cotton bollworm,[link widoczny dla zalogowanych], and pink bollworm, cotton and a small bridge there is a certain resistance to insects, while the cotton aphid , thrips and other pests have no resistance. Second, we must look at is not really buy cotton, cotton if it is true, it must have insect resistance, which is insect-resistant Bt cotton contains a gene itself, as long as the insects will eat poisoning. But if you buy a fake cotton, the cotton insect body itself is not toxic, it is certainly not an insect. Shanxi Academy of Agricultural Sciences, such as cotton are cultivated cotton Jinmian the 26th, the cotton body itself contains a toxic protein in insect-resistant Bt gene (Bacillus thuringiensis rod Yin), this insect-resistant genes is through bio-engineering methods imported conventional cotton varieties, which thus resulted in insect resistance, and the average conventional cotton is no such insect-resistant genes. Because cotton more Therefore, farmers buy seeds repeated reminders to the formal seed certain business units to buy, do not plan to buy cheaper from private hands to prevent fraud. Third, a hybrid Bt cotton and conventional cotton, new cotton 33B, new cotton 32B, CCRI 30 and 26, such as cotton, Jin, purification and rejuvenation as long as the selected species do well to stay on good seed can be planted year after year; and hybrid cotton, such as CCRI 29, CCRI 38, Lu H9513 and other species, only the first generation hybrid plant can not be planted hybrid second generation. Some farmers do not know what the conventional cotton. What is the hybrid cotton, is a misconception that as long as the insect-resistant Bt cotton to be year after year, generation to generation insect-resistant, the second generation of hybrid cotton, the third generation for the species used. And so it was a serious separation of individual plant varies. Insect performance and yield and quality dropped significantly. Fourth, the cotton is often outcrossing crops, cross-pollination rate is generally 10%, high up to 20%. In the current family-based mode of operation under the contract, the other species around the cotton farmers can not, so that other cotton insect-resistant cotton pollen must be passed, causing mixed, there hybrid strains. Hybrid strain is not resistant to bollworm, cotton bollworm damage not only in its plant on, but also migrated to the damage around the cotton plants, causing damage. So pay attention to conventional cotton and hybrid cotton seed production complex security problems. Fifth, the current promotion of cotton varieties, insect and strong early, mid and late resistance to gradually weaken. Meanwhile, strong resistance to young larvae,[link widoczny dla zalogowanych], old larvae of resistance is weak. Therefore, according to the cotton bollworm occurs in algebra and time, must pay attention to pests situation occurs,[link widoczny dla zalogowanych], do surveys, close surveillance, once the serious pests, to control targets, chemical control should be immediately and other control measures . Hou Yao-Xian Li Xiangyuan County meritorious service in 2000 per capita income of farmers 2,556 yuan, compared with growth of 1788.2 yuan in 1997 Jj42.9%. A
More articles related to topics：

[link widoczny dla zalogowanych]

[link widoczny dla zalogowanych]

[link widoczny dla zalogowanych]