What is Bt transgenic zahuishi?

What is Bt transgenic zahuishi?

Beijing News weekly of the new knowledge

At the end of the 19th century, called damping-off diseases of bacterial diseases struck Japan sericulture.

1901, bacteriologists ishiwatari propagation features successfully separating out the damping of pathogens. However there is no ishiwatari more in-depth study, nor timely publication of research results. 10 years later, Germany scientists barlin NA (ErnstBerliner) isolation of the pathogen. He did not know ishiwatari propagation features of discovery, and name it Bacillus thuringiensis (Bt).

However, Bell linnarp soon after the Bt Media lost.

At that time, people have not fully recognize the value of the use of Bt, almost and the tremendous impact of future micro-organisms to pass up. Fortunately the Mattes in 1927 to isolate the Bt.

Soon, scientists discovered that Bt will kill the animal the Lepidoptera (butterflies and moths), on the other animals but has no effect.

At the end of the 1920s, the United States Government try Bt control forest pest gypsy moth, the effect is good. France in 1938, successfully developed the first commercial Bt insecticides. To the 1950s, Bt as a green organic pesticides, in the United States began to be applied on a large scale.

Bt as biological pesticides is also very obvious defects.

It is expensive, but also not stable. As IRS agents, it is very easy to be washed, UV exposure have quickly been decomposed. As the more expensive chemical synthetic pesticides, Bt pesticide market share significantly down, only those who engage in organic cultivation of talents will use it. However, synthetic pesticides on the environment, a lot of damage, but also a threat to the health of mankind itself.

This problem solved, thanks to the birth of modern biotechnology.

In the mid-1950s, scientists find Bt protein on the toxicity of some insects from spore formation of crystals of the protein. In 1981, the scientists of this protein purification and named cry. Then they clone out the cry of the gene. A few years later, the United States scientists put the cry of the gene into maize and cotton. In 1996, transgenic maize and cotton in the United States successfully on the market. Has not yet found them to have any negative effects on human beings. This genetically modified crops for environmental contribution is enormous. In the United States, transgenic cotton for reduced pesticide usage rate of 82%. But in China, planting genetically modified cotton also leaves reduced pesticide usage rate of 60%-80%.

We are talking about Bt transgenic, in fact it is the cry of genetically modified.

In half a century, scientists have made innumerable experimental evaluation of cry proteins in security. Many scientists using purification cry protein feeding mice and found that its oral 3.8 per kg body weight-5gcry protein are secure. Prior to this, the code has also been invoked beijingkejibao Huazhong agricultural University, College of life science technology heuristics of President Zhang e-mail reply that genetically modified rice Bt protein content of not more than 2.5 µg/g "weight 60 kg person eat 120 tonnes of rice" is okay. Furthermore, Bt protein in the human body cannot be accumulated. If you put it to join the gastric juice extracts, all of the Bt protein are 0-7 minutes is broken down. This is an easy to digest proteins.

To cry proteins in toxicological studies indicate that it itself is non-toxic, but you can be certain insect enzyme activation, and also on the need and intestinal receptor specific binding to work.

Therefore, the vast majority of humans, animals, it is non-toxic. Similarly, tomatine, capsaicin can kill insects, but it does not prevent the tomato and pepper into people's favorite food.

From 1 million years ago primitive agriculture produce onward

s, man began to wild plants into the "crop". The last century, produced by mutation breeding and breeding technology so that we can change the crop of the genome. However, this change is random, with many uncertain factors. The birth of transgenic technology so that humans can enable crop more effectively meet your needs. It is through countless generations to transform those wild species, the shelves of food will become more and more rich and delicious, increasingly health, a growing security.

□ Arabidopsis (United States biology majors)