The cumulative annual promotion is more than 1.5 million mu, and the annual income of vegetable farmers in Yunnan exceeds 5 billion yuan. Comprehensive prevention and control: fight against vegetable "cancer"

  Production practice tells us once again that due to the complexity and change of vegetable virus diseases, it is impossible to fundamentally solve the problem by adopting a single method such as the use of anti-virus disease varieties. The prevention and control of vegetable virus diseases must take comprehensive prevention and control measures.

  Professor, School of Plant Protection, Yunnan Agricultural University

  Li Fan

  In the past, it was half-profit and half-loss growing vegetables, but now it has steadily expanded production and increased income.

  The vegetable industry, which is mainly based on solanaceous vegetables such as tomatoes and peppers, is a hope industry supported by Yunnan Province.

  However, for a long time, there has been a "stuck neck" problem that has plagued the development of the vegetable industry in Yunnan. Many vegetable farmers have lost everything because of the raging vegetable virus disease. Therefore, the "virus disease" is also called the "cancer" of vegetables.

The reporter recently learned from the agriculture and science and technology departments of Mile City, Honghe Prefecture, Yunnan Province and Yuanmou County, Chuxiong Prefecture that Liu Yong, a scientist in the national bulk vegetable industry technology system for viral disease prevention and control, and a researcher at the Hunan Academy of Agricultural Sciences, led the team, stationed in Yunnan all year round, serving vegetable farmers. At present, remarkable results have been achieved in the prevention and control of local vegetable virus diseases, realizing the double guarantee of increasing the income of the local vegetable industry and filling the "vegetable basket".

  Vegetable field virus disease is raging, and vegetable farmers are swallowing tears

  For a long time, tomato virus disease in Honghe Prefecture, Yunnan Province has been seriously damaged.

  Dwarfing and yellowing tomato "trees", as soon as they are full of green fruit, there are spots and stripes, and even rotten fruit, all of which are caught off guard.

  When the seedlings are planted and planted, they are full of expectations for a bumper harvest; months of hard work have resulted in almost no harvest.

Truckloads of green fruits are piled up on the ridge outside the shed, Bai Jie, a tomato grower in Huangliantian Village, Pengpu Town, Maitreya City, wanted to cry without tears: "Before 2015, the tomato and pepper I planted had very serious virus disease, and virus disease occurred. In the future, the finished products of tomatoes and peppers will be small and ugly, full of spots and defects, and the commerciality is almost zero.”

  Shi Xisheng, a major vegetable grower in Baijietong Village, introduced that the occurrence of vegetable virus diseases is related to varieties, viruses, insects and weeds. There is no way to take single prevention and control measures. They can only watch a ridge. Tomatoes are wilting.

  "Vegetable viruses are mainly spread by seeds and insects, and more than 90% of them are insect-borne viruses. Seed-borne viruses can be killed by seed disinfection, but it is much more difficult to control insect-borne vegetable viruses." Liu Yong According to a reporter from Science and Technology Daily, insect-borne vegetable viruses often first spread on broad-leaved weeds around vegetable fields. Weeds infected with the virus will release chemicals such as neophytadiene, attracting whiteflies, thrips, and aphids. Waiting for insects to feed, this is also the time when the accumulation of viruses reaches its peak.

After a large number of insects feed on the poisonous weeds, they migrate to the surrounding vegetable bases, and they will spread the virus to healthy vegetable plants.

  "If vegetable varieties are not resistant to viral diseases, the virus can infect and cause harm. Therefore, whether a viral disease breaks out, apart from the virus itself, is often related to the type and number of broad-leaved weeds that carry the virus, and virus-transmitting insects. It is closely related to whether the vegetable variety is resistant to the virus," said Li Fan, a professor at the School of Plant Protection at Yunnan Agricultural University.

  Is it letting the disease run its course?

Or proactive prevention?

At this time, both Liu Yong and Li Fan paid attention to the "embarrassment" of Yunnan vegetable farmers.

  Liu Yong led the team through 25 years of tackling key problems. On the basis of long-term systematic research and monitoring of vegetable virus diseases in more than 3,500 townships and villages in more than 580 key vegetable-producing counties across the country, the research and development of a "toxin source, selection of varieties, and suppression of viral diseases" was carried out. The comprehensive prevention and control technology system of vegetable virus diseases with the core of seed transmission, prevention of transmission, and resistance increase has made a combination of "cancer prevention" and "cancer treatment".

  "One thing down, one thing", biological control technology to deal with cunning virus

  There are about 30 kinds of viruses that harm vegetables in Yunnan, causing more than half of the losses to tomatoes, peppers and other vegetables all year round, and even causing production and harvest in severe cases.

  "The actual production tells us again that due to the complexity and change of vegetable virus diseases, it is impossible to fundamentally solve the problem by adopting a single method such as the use of anti-virus disease varieties, and comprehensive prevention and control measures must be taken to prevent vegetable virus diseases." Li Fan said.

  In the face of vegetable virus, the team worked together and used multiple sets of technologies in various aspects to help farmers successfully resist vegetable "cancer" on a large scale.

  Photosynthetic bacteria are a class of bacteria that can synthesize nutrients required for growth by using light as a substrate for small molecular compounds in the energy environment.

Photosynthetic bacteria are the earliest prokaryotes with primitive photosynthetic systems on earth, mainly including green sulfur bacteria, purple sulfur bacteria, green non-sulfur bacteria, and purple non-sulfur bacteria, about 120 species.

"The use of photosynthetic bacteria is critical to the prevention and treatment of vegetable 'cancer'," said Liu Yong.

  Liu Yong's team started the research with a large range of samples. They screened from more than 50,000 photosynthetic bacteria isolates to control the host plant's resistance to viral diseases. The bacteria agent of Rhododendron thiophila, which was fermented, produced a 3-amino acid compound. The short peptide can penetrate into the inside of the seeds, so as to passivate the cucumber green mottle virus carried by the seed coat and seed embryo, so that the virus rate of seedlings is almost 0; Rhodopseudomonas marsh (a kind of photosynthetic bacteria) with Rhp-PSP protein, both indoor inoculation and large-scale field application show that the fermentation broth of Rhodopseudomonas marsh containing Rhp-PSP protein can completely inhibit most of the current The infection of tomato and pepper by the virus is as high as 90%.

  Regarding how to block the way insects transmit viruses, Liu Yong's team also invented a nanomaterial-based insecticide, which is valid for 30-45 days after being applied to the roots of crops such as tomatoes, and the frequency of insect control insecticides is reduced from 7-9 The number of times is reduced to 1 time, and the residue of this pesticide is almost 0 when the tomato is mature, which greatly reduces the pollution of the pesticide to the environment and agricultural products. According to their years of experience, when the virus is first infected, more than 90% of the virus comes from vegetable fields. There are 10 broadleaf weeds around, so eradicating these weeds can greatly reduce the amount of virus.

In order to make it easier for farmers to master and apply the above-mentioned technologies, Liu Yong and his team members simplified it into "understanding paper" and simplified it into a simple diagram.

"Understanding Paper" has been widely promoted in many provinces and has achieved significant economic, social and ecological benefits.

  Zhou Yunbin is the head of the Yunnan market of Guangxi Huanshang Agricultural Technology Co., Ltd.

He told reporters that by promoting the "Zuanhong 5424" and "Miller 218" tomato virus-resistant varieties and "clear paper" selected by Liu Yong's team, the problems of slow color change, poor color change and low yield of some tomato varieties have been solved. Commodity and shelf life are not inferior to foreign varieties, and the adaptability is far better than that of foreign brands, and the seeds of bulk vegetables are firmly in their hands.

  Credit science uses science, vegetable farmers expand production and increase returns to real money

  Li Fan's team and Liu Yong's team have carried out systematic research on viral diseases in major vegetable producing areas in Yunnan since their cooperation, and have ascertained the types of viruses and the regularity of occurrence and prevalence of these vegetable crops. Introduced into Yunnan, carried out test demonstrations and large-scale application in Kunming, Honghe, Chuxiong and other places, removed broad-leaved weeds around vegetable fields in time before vegetable planting and planting, and selected varieties resistant to related virus diseases according to the types of virus diseases in the townships. Microbial pesticides can kill the virus carried by seeds and improve the resistance of plants to viral diseases, and then skillfully apply nano-particle pesticides to kill virus-transmitting insects.

  Under the guidance of scientific researchers, the farmer Shi Xisheng used the tomato varieties and microbial pesticides and nano-insecticides developed by Liu Yong's team, according to the concise "clear paper" instructions. In the previous season, it was 15 times, and it was enough to reduce it to 3 times." Shi Xisheng said that since the pesticide application method was changed to root irrigation, and there was no air pollution, the income of tomato per mu increased by more than 15,000 yuan. Yuan.

  Like Shi Xisheng, Bai Jie is also a beneficiary of new technologies and new achievements.

"There is basically no problem with tomato and pepper virus diseases now. The advantage of this technology is that it is easy to learn, understand and master." Bai Jie said that in the past few years, he only dared to grow five or six acres of tomatoes, but now he has gradually mastered comprehensive prevention and control. With the new technology, the planting area of ​​his family has increased to 13 acres this year.

In the first quarter of the spring this year, the bunches of fruit in the greenhouse were large and solid, with almost no diseased or rotten fruit. When the market conditions were at their best, they could be sold at a good price of 7 yuan per kilogram.

In the past few years, vegetable enterprises and large planters in many places in Yunnan have transformed to believe in science and use technology, and have squeezed foreign brand tomato varieties out of the main vegetable producing areas in Yunnan.

In 2021 alone, more than 30,000 mu will be promoted and applied in Honghe Prefecture. It is conservatively estimated that an increase of 15,000 yuan per mu will increase the income of local farmers by more than 450 million yuan a year.

At the same time, in Yuanmou County, through the application of comprehensive virus disease prevention and control technology in recent years, the tomato planting area has quickly recovered to more than 80,000 mu.

  Chen Jianping, an expert in plant pathology and academician of the Chinese Academy of Engineering, believes that the comprehensive prevention and control technology for vegetable virus diseases developed by Liu Yong's team has reached the international advanced level as a whole, among which the anti-viral disease microbial pesticides have reached the international leading level; some technologies have been listed as the main promotion by the Ministry of Agriculture and Rural Affairs. At the same time, it has also been widely welcomed by vegetable growers, and has been widely promoted and applied in major vegetable producing areas in the country.

  At present, this technology has been widely applied in major vegetable producing areas such as Jinning District and Xundian County of Kunming City, Yuanmou County of Chuxiong City, Mile City of Honghe Prefecture, and Longyang District of Baoshan City, Yunnan Province, with a cumulative annual promotion area of ​​1.5 million More than 5000000 yuan per year for Yunnan vegetable farmers.

  Related Links

  Biologics are safe and effective for vegetables

  There are many kinds of virus diseases that damage vegetables. At present, there are about 70 kinds of viruses that damage vegetables in my country, but the main ones that cause large-scale damage in production are tobacco mosaic virus, cucumber mosaic virus, tomato spotted wilt virus, tomato chlorosis virus, Broad bean wilting virus, tomato yellow leaf curl virus, turnip mosaic virus, cucumber green mottle mosaic virus and other 8 viruses, of which cucumber green mottle mosaic virus is a seed-borne virus, and the other 7 viruses are mainly insect-borne. Some seed coats can be carried but not harmful.

  For so many viral diseases, biological agents are relatively safe and effective against them.

For example, cucumber green mottle mosaic virus can infect seed embryos, so the key to the prevention and control of the virus is to kill the virus carried on the seed embryos. Seed dressing with preparations, but high temperature treatment is easy to damage the seeds, which is difficult for farmers to master, and chemical treatment is likely to cause pollution to the ecological environment, so relatively speaking, biological preparations without the above shortcomings are the safest and most effective method.

Keywords: