A common plant virus that transforms plant viruses into nano-sized agricultural materials beneficial to crop growth.

In order to reduce the harm caused by diseases and insect pests, farmers will cooperate with the crop growth cycle and apply pesticides appropriately. As most pesticides are not specific, in case of improper application, it may destroy the food web around the farmland, and then affect the balance of the surrounding ecosystem. With the rise of the awareness of environmental protection and the introduction of the concept of safe use and management of pesticides, in addition to eliminating agricultural pests and regulating the growth of agricultural and forestry crops, we should also avoid causing the load on the regional environment. Therefore, the application of pesticides is also gradually towards the thinking of precision farming (precision farming) management and practice. In order to accurately apply pesticides to agricultural land and reduce environmental impact, the research team of the University of California, San Diego (University of California, San Diego) used plant viruses as drug delivery carriers to develop highly permeable nanopesticide (nanopesticide).

In order to develop materials with local sustained release and easy degradation in the environment, the research team focused on the development of nano-scale materials. Different from the previous synthetic nanomaterials, the research team used plant virus particles as drug carriers and selected tobacco micro-green mosaic virus (tobacco mild green mosaic virus, referred to as TMGMV), cowpea mosaic virus (cowpea mosaic virus, referred to as CPMV) and acid pulp mosaic virus (acid pulp mosaic virus, referred to as PhMV) as research materials, and mesoporous silica nanoparticles (mesoporous silica nanoparticles). MSNPs), poly (lactic acid-co-glycolic acid) (poly (lactic acid-co-glycolic acid), PLGA) and other common drug delivery systems were compared. The team first measured the mobility (mobility) of these materials in the soil medium, and combined with computer simulation of the moving depth of the material, the appropriate dosage, drug release time and other data found that tobacco green mosaic virus and cowpea mosaic virus can spread to the soil 30 cm below the surface, and accurately slowly release nematodes to effectively control nematodes harmful to plant roots. Synthetic nanomaterials can only move to a depth of 12 centimeters below the soil, providing more comprehensive protection for deep-rooted crops.

In the face of better moving effect, the team inferred that this may be related to the special geometric structure and chemical composition of the virus surface, so that the viral material can easily penetrate the soil pores. Among these geometric structures, the long rod-shaped tobacco micro-green mosaic virus is better than other spherical nanomaterials, and its rod-shaped surface has a variety of chemicals, which enables it to interact with different soil mediums. Therefore, the nanomaterial can have a better performance in the soil.

The research model established by the research team helps to improve the research and development process of other biological materials, requiring simple equipment to condense the research that would have taken one month to four days with computer-aided simulation. This study also makes a significant contribution to precision agriculture (precision agriculture), pest control and management techniques and environmental safety.

The study was funded by the National Science Foundation (NSF) and the National Institutes of Health (NIH).