Everyone knows that cotton is a highly demanded raw material for knitted fabrics. Today, China ’s Knitting show introduces a new technology for cotton growing! Recently, the cotton team of the State Key Laboratory of Crop Genetic Improvement of Huazhong Agricultural University has received good news. The team has made a series of breakthroughs in the research of cotton gene editing systems. By implementing precise targeting, their new system can successfully eliminate the "spite" in cotton genes. "To escort high-quality cotton production.
The most frequently grown bugs on cotton plants are aphids and bollworms. These bugs will bite off the young leaves and stems of the plant. They will also inhibit flowering, accelerate leaf shedding, let the leaves roll, and the amount of cotton produced will Affected, they keep cotton from developing in the normal way and prolong flowering time. When pests appear, spray with a suitable insecticide.
4 sets of cotton gene editing systems go global
"In the field of cotton gene editing, we are in an international leading position." The team professor Jin Shuangxia said that the team has developed 4 sets of cotton gene editing systems, which are widely used worldwide.
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As early as 2013, the team tried to introduce rice and Arabidopsis CRISPR editing systems into cotton without success. After continuous trials, the team changed the regulatory elements to cotton's own elements based on the biological characteristics of cotton. The first cotton gene editing system was created in 2017 with an editing efficiency of 85%.
Scientific research continued, and the second, third, and fourth sets of cotton gene editing systems were successively successful. The off-target effect test proves that the gene editing system created by the team has high accuracy and extremely low off-target rate. "Precision shooting is the key to the success of gene editing," said Jin Shuangxia.
The internationally renowned academic journal "Plant Science Trends" also invited Jin Shuangxia's team to write a summary of the research results and publish it online. Recently, the team established the first efficient CPF1 and single base editing system in cotton for the first time to further enrich the cotton gene editing tool library.
Insect pest-inducing genes in loquat crops
Gene editing technology targets specific genes in the organism, or prevents them from producing undesirable characteristics, or modifies them to change in a positive direction.
"Compared with or even beyond cloning technology." Jin Shuangxia said that gene editing technology can carry out targeted transformation of DNA sequences at the genome level. Compared with previous physical and chemical mutagenesis, it is more accurate and convenient. "Which fight" is of great significance to many basic researches in human medical treatment, genetic disease treatment and improvement of agronomic traits of animals and plants and life sciences.
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Wu Jinshuangxia said that the occurrence of crop diseases and insect pests, such as rice, cotton, and wheat, was caused by the "internal and external cooperation" of crop genes and viruses. There are pest-inducing genes in crop genes, which are usually in a silent state. Once the virus strikes, these "spiders" become active and cause crop diseases. Nowadays, they are usually controlled by external drug spraying or biological resistance.
If you use gene editing technology, you can accurately find the "spider" in the gene and accurately attack it, and knock out the "spider" gene, so the crop will not be infected.
Cultivate "green" cotton with abundant genetic materials
The apple is easy to change color after cutting, it is ugly and not delicious. Apple can't control technology, but technology can change Apple.
Currently, foreign agricultural companies have developed non-browning apple varieties and marketed them in the United States. This apple uses gene editing technology to knock out the gene that causes browning, and it will not be oxidized and discolored in the air after being cut.
This is just a small trial of gene editing technology in crop breeding. Gene editing applications are endless. Jin Shuangxia introduced that, in addition to apples that do not change color, the technology can also breed new varieties faster and more efficiently, greatly increasing crop yields, improving the ability of crops to resist drought and pests, and increasing nutritional value.
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At present, the Jin Shuangxia team has used gene editing technology to develop cotton herbicide-resistant materials to achieve resistance to herbicides, which has been successful in small-scale experiments. At the same time, the team used high-throughput gene editing technology to saturate thousands of cotton genes to create rich genetic materials and cultivate more "green" cotton that is resistant to pests, high yields and good quality.
Wu Jinshuangxia believes that although the source of gene editing technology is abroad, a large number of domestic researchers are developing original gene editing systems in important crops such as rice, corn, wheat, and rapeseed to seize the commanding heights of crop gene editing.
Source: Global Textile Network
The pretreatment of pure cotton or polyester / cotton fabric is mainly to remove impurities from cotton fibers, so that the fabric has good printing and dyeing processing performance. The conventional desizing, scouring, and bleaching processes are set for different impurities. However, it is found in production that the above processes are not specific. What is the situation? China Knitting Fair will explain for you.
Bleaching is to turn the textiles containing pigments into colorless textiles. Generally, oxidants are used for bleaching. Dyeing is to turn colorless textiles into colored ones, and dyes are usually used for dyeing. If pure white cotton is produced, the printing factory will do two bleaching, the first time is called semi-bleaching and the second time is called full-bleaching. If producing colored cotton cloth, the printing factory should first do half-bleaching, and then dye it.
Also note: bleaching oxidants, not whiteners. Bleaching and whitening work on different principles. The role of bleaching is to remove pigments; the principle of whitening is to radiate blue fluorescence to achieve the purpose of "covering yellow".
At the same time as desizing, the oil and wax in the raw cotton components also start to saponify, which has a certain scouring effect. During the scouring process, not only the grease, wax, pectin, ash, lignin, etc. in the cotton components are removed, the slurry is further removed, and some pigments can be removed.
In the bleaching process, hydrogen peroxide not only removes pigments, but also has a certain removal effect on residual slurry and some impurities.
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In the conventional process, caustic soda is used as desizing and scouring, while in the hydrogen peroxide bleaching process, caustic soda is only used to adjust the pH value of the bleaching solution.
Since the alkali is an activator of hydrogen peroxide, if the alkali concentration is increased, the hydrogen peroxide is decomposed to generate H00-, and at the same time the reaction speed is increased, resulting in a large amount of reactive power consumption of the hydrogen peroxide. More importantly, due to the excessive activation of hydrogen peroxide, the formation of H00 · radicals is promoted, which has certain damage to the fibers.
In addition, in the production of fabrics, water, equipment and other heavy metal ions such as Fe2 +, Cu2 +, etc. will inevitably cause the hydrogen peroxide to crack and decompose, causing chain reactions.
Therefore, in the one-bath method of withdrawal, cooking, and bleaching, the amount of hydrogen peroxide in the strong alkaline bath must be strictly controlled, and its stabilizer must meet three functions: ① stabilizing perhydroxyanion (HOO-); ② shielding heavy metal ions; Mass production of perhydroxy radicals (HOO ·).
In the conventional bleaching process (pH 10 to 11), the hydrogen peroxide is activated by alkali to form HOO-.
At this time, water glass, because of its polymer network structure, shields heavy metal ions, can adsorb Fe2 + and block HOO—, so that Fe2 + does not undergo a catalytic reaction, and at the same time inhibits the formation and decomposition of H00 · radicals. Water glass can also combine with Ca2 + and Mg2 + ions in the bleach solution to form highly dispersed magnesium silicate and calcium silicate colloids, which are adsorbed on the surface of the catalyst to make it lose its activity and thus stabilize it.
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If water glass is bleached in soft water, instead of stabilizing, it will accelerate the decomposition of hydrogen peroxide due to the increase in pH. However, when the Fe2 + content exceeds the adsorption capacity of water glass, the stabilization effect is weakened. For this reason, although water glass has a good stability effect and is cheap, it cannot meet the above functions in the one-bath method of strong alkali withdrawal, boiling, and bleaching. Therefore, it is unreasonable to use water glass as a stabilizer alone in the prescription. If water glass, magnesium sulfate, and complexing agent are mixed in a certain ratio, it can be suitable for one-bath method of boiling back, boiling, and bleaching.
In addition, the scouring agents and detergents used in the prescription must be resistant to alkali, have good permeability in the alkali bath, have the effects of emulsification, washing, solubilization, and dispersion, and have a high cloud point. If these quality indicators meet If it does not meet the requirements, it will also have a certain effect on the effect of the one-bath method of retreating, cooking, and bleaching. In short, as long as you choose the appropriate hydrogen peroxide stabilizer and scouring agent, penetrant, and control the process conditions, the excessive alkali in the strong alkali is properly resolved , Intensification, stability, etc., will certainly make withdrawal, cooking, bleaching one bath method to achieve the desired effect.
In addition: ① The amount of water glass is too much, and there is more residual hydrogen peroxide, which fails to give full play to the bleaching effect. ② Reduce the amount of water glass and increase the chelating stabilizer. ③ Caustic soda concentration can be appropriately increased, and the rolling rate can be increased. ④The steaming temperature can be increased to 105-110 ℃.
Source: Global Textile Network
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