Do you know the playboy of the insect virus world?

    It is the AcMNPV (Autographa californica nuclear polyhedrosis virus), Which can infect a variety of pests and is considered a big name in the insect virus world. The wild-type AcMNPV mainly targets pests of the family Noctuidae in the field

Flexibility of virus entry mechanism

• Key protein GP64: AcMNPV relies on the envelope glycoprotein GP64 to fuse with the host cell membrane. The receptor-binding domain of GP64 exhibits relatively loose host specificity, recognizing conserved receptors (such as heparan sulfate proteoglycans) on the surface of various lepidopteran insect cells.

• High compatibility with host receptors: Compared to other baculoviruses (such as Bombyx mori nuclear polyhedrosis virus BmNPV), AcMNPV's GP64 protein exhibits stronger affinity for different host cells.

  Like human HIV, nuclear polyhedrosis virus can make infected pests suffer from incurable diseases. This virus is mainly composed of two parts, a large number of polyhedral proteins gathered together to form solid polyhedra several micrometers in size, called polyhedra. Inside the polyhedra, there are many virus particles that can cause disease. Polyhedral proteins are very stable in nature and can protect fragile virus particles from the harmful effects of ultraviolet rays in sunlight. As a result, virus particles can survive for many years in nature under the protection of the protective shell of polyhedra. However, polyhedrin have another characteristic: once exposed to alkaline environments, they are very easy to dissolve, and the digestive juices of pests are extremely alkaline, which is the key to the insecticidal effect of nuclear polyhedral viruses. When pests ingest polyhedra along with food, the polyhedra protein immediately dissolves upon encountering strongly alkaline digestive juices, releasing virus particles that quickly invade the pest's midgut cells and replicate extensively in the nucleus. After the first round of replication is completed, a new generation of virus that expands exponentially is released from the midgut cells into the bloodstream of the pest, causing systemic infection along the bloodstream. It replicates extensively in almost all cell nuclei of the pest, and this process will take 3-4 days. At first, people cannot see significant changes from the infected pests, but in the later stages of infection, the pests' feeding decreases, their body color becomes lighter, and they are less active, which is a precursor to the disease becoming terminal. It is during this period that the task of virus reproduction and offspring is basically completed, and the next step will be to form a protective jacket to enter the harsh external environment and wait for infected individual pests. A large amount of polyhedral proteins were rapidly synthesized, just like wrapping buns. The "skin" made of polyhedral proteins wrapped the "filling" made of virus particles into polyhedral "buns". At this point, when observed under a microscope, there are hundreds of such "buns" in almost every cell of the pest's body, indicating that the pest is still alive. The moment when the "buns" comes out of the cage is a sudden explosive event. The virus's DNA causes the still functional insect cells to start synthesizing protein enzymes that can dissolve cells and chitinase that can dissolve the insect's hard skin. The synthesis of these enzymes will lead to the complete collapse of the entire insect. A slight vibration can instantly transform a seemingly intact insect into a liquid containing countless polyhedral viruses. This is a lethal liquid for pests, but it is very safe and friendly for humans and the environment in which they live, including livestock, wildlife, birds, and fish.

  Compared with other biological or chemical pesticides, the biggest characteristic of insect viruses is their infectivity, long-term effect, ability to control pest density, no need for frequent pesticide application, and significant reduction in the frequency and dosage of pesticide use by farmers. For example, in our own experimental field, in the first year, we used the SeNPV three times in a row with an interval of 10 days, and the harm of beet armyworm was controlled in the field. In the second year, no adult beet armyworm was found in the field monitoring, and in the field that was 50 meters away and did not use SeNPV, beet armyworm still occurred in the second year.

  At this time, the 12th Biological Pesticide Development and Application Exchange Conference was held on April 15th in the heroic city of Wuhan. In fact, there is also an insect virus in the story of the heroic city Wuhan that has made contributions to humanity. As an important member of microbial pesticides, it plays an important role in green prevention and control. Academician Gao Shangyin of Wuhan University established the first virus department in China and began researching insect viruses.

  Wuhan Unioasis Biological Technology Group Co., Ltd. was co founded by experts and professors from Wuhan University in 2002. It is a high-tech enterprise that integrates the R&D, production, and sales of beneficial microorganisms such as insects, viruses, bacteria, and fungi. It is a benchmark enterprise in the domestic insect virus new biological pesticide industry with the largest variety of products, the widest coverage, and the strongest production capacity. We have outstanding research advantages and have established the "Green Prevention and Control Industry Development Research Institute" (the first research institute to be settled by Academician Chen Zongmao), as well as the "Green Prevention and Control (Qiandao Lake) Industry Development Research Institute" in Chun'an County. We established the "Wuhan University & Wuhan Unioasis" Joint R&D Center with Wuhan University and gained the recognition of the Hubei Provincial Department of Science and Technology. We have jointly established the "Microbial Application Technology Innovation Center" with the National Biopesticide Engineering Technology Research Center. We are committed to developing modern smart agriculture led by microbial agriculture, which can promote the development of modern smart agriculture civilization and enhance the well-being of the Chinese nation and even the world's people. At present, there are 12 registered varieties of insect virus biopesticides in China, with 8 from Wuhan Unioasis. Virus products have obtained organic input certification, covering multiple fields such as vegetables, rice, tea, cotton, wheat, fruits, traditional Chinese medicine, forest and urban health pest control.

  As a pioneer in biological pesticides and a pioneer in green prevention and control, Wuhan Unioasis has been interviewed by CCTV Economic Channel's "Economic Half Hour" for three consecutive times since 2013. In 2018, Unioasis was invited to participate in the China (Qingdao) SCO Summit and delivered a keynote speech titled "Wuhan Unioasis Supports the Agricultural Development of SCO Countries" as the only representative of a company, proposing the concept of "double reduction and double saving", which was highly concerned by participants from various countries. In 2020, Unioasis was invited to participate in the "Qiandao Lake Summit Forum" and delivered a keynote speech titled "The Three Forces of Protecting Lucid waters and lush mountains". People, technology, and industrialization are these three important forces to solve the agricultural non-point source pollution problem in Qiandao Lake.

  As a pioneer in biological pesticides and a pioneer in green prevention and control, Wuhan Unioasis has been interviewed by CCTV Economic Channel's "Economic Half Hour" for three consecutive times since 2013. In 2018, Unioasis was invited to participate in the China (Qingdao) SCO Summit and delivered a keynote speech titled "Wuhan Unioasis Supports the Agricultural Development of SCO Countries" as the only representative of a company, proposing the concept of "double reduction and double saving", which was highly concerned by participants from various countries. In 2020, Unioasis was invited to participate in the "Qiandao Lake Summit Forum" and delivered a keynote speech titled "The Three Forces of Protecting Lucid waters and lush mountains". People, technology, and industrialization are these three important forces to solve the agricultural non-point source pollution problem in Qiandao Lake.

The picture below shows the differences between the novel coronavirus and insect viruses.

  The biggest feature of insect viruses compared to other biological or chemical pesticides is their infectivity, long-lasting effect, ability to control pest density, no need for frequent pesticide application, and significant reduction in the frequency and dosage of pesticide use by farmers. For example, in our own experimental field, in the first year, we used the SeNPV three times in a row with an interval of 10 days, and the beet armyworm was controlled in the field. In the second year, no adult beet armyworm was found in the field monitoring. In the field that was 50 meters away and did not use SeNPV, the beet armyworm still occurred.

  When promoting the use of the Spodoptera litura nuclear polyhedrosis virus in the planting base, I saw that farmers used chemical pesticides every 3-5 days, which was very difficult. I suggested that the planting technician at the base hang a Spodoptera litura trap to monitor the density. He thought that he often sprayed pesticides, there must not be many pests. We hung a Spodoptera litura trap in the greenhouse and observed the results a week later. We found that the collection bottle was filled with dead adult Spodoptera litura. How could chemical pesticides with a control effect of over 90% still have such a high insect density after frequent spraying? He was very shocked to see this result. Why are there still so many insects in the field? Chemical pesticides are gradually decreasing in the field, while insect viruses are gradually accumulating in the field. As time passes, insect viruses continue to proliferate in the field, gradually controlling generations of mixed pests and keeping their density within the economic threshold.

The picture below shows the condition of the Spodoptera frugiperda/Fall armyworm after being controlled using insect viruses.

  1.Set up traps The picture below shows the condition of the grassy noctuid moth after being controlled using insect viruses.etable fields to monitor the specific time of pest occurrence. For example, traps for beet armyworms and spodoptera litura are set up in vegetable fields in May. Based on the monitoring results, apply AcNPV.BT within one week after trap the adults, and apply again after 10-15 days according to the monitoring situation, control the pests in the early stage of pest occurrence and during the peak hatching period of eggs.

2.Apply pesticide after the sun sets, the noctuid insects in the vegetable fields come out at night and can eat the freshest insect viruses, which has a much better effect.

3.If there is already an outbreak in the field and the insects are third instar (visible to the naked eye), use low toxicity, low residue and environmentally friendly chemical agents to control the density first. After 3-5 days, use insect virus biological agents to control pests in both the short and long term.

When using insect virus biologics throughout the process, we found a benefit, as shown in the following case:

1. On June 6, 2018, cowpeas were sown and solar frequency vibration ultraviolet insecticidal lamps were installed in the field (reducing the underground beetle to no longer require control)

2. On June 7th, two sets of beet armyworm traps and sexual attractant cores were installed. On June 24th, three adult beet armyworms were captured. On the evening of June 29th, the AcNPV.BT was sprayed, and the harm was controlled

3. Replace the lure core on July 6th;

4. After July 16th, cowpeas were harvested successively without the harm of beet armyworm, and the occurrence of pod borer and bean field borer was relatively mild without the use of other pesticides for control.

5. Natural enemies such as frogs, mantises, step beetles, and ladybugs have been found in the fields, and earthworms can be seen everywhere in the soil.

6. The next crop of cabbage did not show any damage from beet armyworms, and adult beet armyworms were trapped from other land plots. Aphids occur less frequently, and the number of ladybugs in the field increases.

7. In 2019, chili peppers were planted and beet armyworm traps were hung in the fields. No adult beet armyworm was found, and no damage caused by beet armyworm was found on chili peppers. Adult cotton bollworms and tobacco green worms were found in the hanging traps, and the HaNPV was used for prevention and control. The number of traps gradually decreased.

The use of green pest control technology with insect viruses as the core has gradually restored the field ecology, protected natural enemies of pests, and thus controlled the occurrence of other pests.

This green prevention and control technology with insect viruses as its core can only achieve unimaginable results after practical experiments in farmland. Prevention first, and it is necessary to promote truly practical, farmer recognized, and usable technologies, turn on the insecticidal lamps installed in the fields and play a real role. There is no need to hang too many traps, just do a good job of monitoring. To truly unleash the power of insect viruses, using an additional ton of biopesticides can greatly reduce the use of chemical pesticides.