Why we contacted

To conduct background research on agricultural disease prevention and verify the value of the project.

Interview Content

Professor Jiao affirmed our idea of using phages to address bacterial diseases. He pointed out that VLPs are currently a common method for delivering substances to eukaryotic cells, while targeted delivery systems for bacteria are relatively scarce in existing research. Therefore, using phages to deliver toxin plasmids is not only an efficient bactericidal method, but also can serve as a broad-spectrum delivery system by modifying the packaged substances. For this reason, he believes PhAgri has excellent application prospects.

However, he also emphasized that to ensure the safe use of phages, it is necessary to weaken or even modify phages to eliminate their replication ability. He thus suggested that we search for relevant literature to identify suitable modification methods and genome introduction techniques.

Why we contacted

To conduct preliminary background research on agricultural disease prevention and verify the value of the project

Interview Content

In the interview, Professor Zhou fully recognized the promising prospects of our project from two aspects: product trends and existing hardware development. In terms of hardware development, he noted that although the establishment of smart agriculture systems in recent years faces challenges like the need for mechanization advancement, such systems can provide better hardware conditions for the implementation of our project. He clearly acknowledged the advantage of our project in adapting to smart agriculture systems, believing that the project demonstrates a long-term development vision.

At the same time, Professor Zhou put forward key suggestions for the project's advancement, emphasizing that our product must prioritize economic costs and operational complexity to improve farmers' acceptance. He mentioned that the current acceptance of biopesticides among mountain farmers mainly depends on the balance between operational complexity, cost and control efficacy. Even if a product has good control effects, it may be difficult for farmers to accept if it is too expensive or complicated to operate. These suggestions provided important references for optimizing the project direction.

Why we contacted

Understand the pesticide application practices of frontline workers and clarify the project’ s advantages.

Interview Content

In terms of pricing, farmers' sensitivity to pesticide costs varies by crop type. For ordinary open-field crops (e.g., eggplants, peppers), farmers tend to choose cheap traditional pesticides; for high value-added premium crops (e.g., potted watermelons, tomatoes), they are more willing to accept high-cost new biological agents (such as phages).

Currently, the use of chemical pesticides lacks a fixed schedule - application is triggered by manual visual observation of diseases and pests, relying heavily on experience. Green pest control is the primary approach, and fungicides are sprayed in advance during hot and humid weather to prevent diseases. Efficacy is only judged by the apparent condition of leaves, and there is a general need to reduce chemical pesticide use.

In terms of spraying methods: UAVs can cover 100-150 mu (1 mu ≈ 0.0667 hectares) per hour with a 10-minute fast charge via generator; there are also hybrid (oil-electric) spraying tanks that can climb slopes up to 50° and cover approximately 40 mu per 2 hours, saving 30% water. These devices are primarily compatible with emulsions and aqueous formulations, which require dilution by 800-1000 times before use.

Why we contacted

Understand the characteristics of target pathogens (e.g., Pseudomonas syringae) and existing prevention and control methods.

Interview Content

The characteristics of the target pathogen (Pseudomonas syringae):It is a major pathogen causing bacterial diseases in plants, primarily infecting dicotyledonous plants (e.g., tomatoes) through stomata and other entry points. It causes cell death and lesion formation within 7-8 days, following a cycle of “leaf lesions - soil residue - reinfection in the next year." Due to the similar infection mechanisms of its pathovars —— all of which are harmful and only differ in virulence.

Existing prevention and control methods:Traditional pesticides (copper ion formulations, antibiotics) can inhibit initial infection but are ineffective against vascular diseases. They also damage soil, pollute water bodies, and have a utilization rate of only 20%-30%. Meanwhile, the professor emphasized the need to be vigilant about pathogen resistance and recommended integrated pest management. He affirmed the biosafety of our project's design of non-replicable phages and also raised questions about phage selection, providing inspiration for project optimization.

In addition, Professor Liu Jun shared insights into the dietary culture of tomatoes in Western countries, emphasizing that tomatoes are highly important economic crops in the West.

Why we contacted

Learn from mature prevention and control models, and compare and improve the project’ s advantages.

Interview Content

Regarding pathogens causing plant bacterial diseases: Most are bacteria of the genus Pseudomonas —— these Gram-negative bacteria share significant commonalities and can infect various crops such as strawberries, cucumbers, and rice, causing severe diseases. Pseudomonas syringae also belongs to this genus, confirming the rationality of our project's focus on this pathogen and its universal applicability.

Regarding the green pest control system: Wuda Oasis Group's “5+2" system is highly representative. The “5 core technologies" include simultaneous application of fertilizers and bacteria, insect virus-based pest control, etc.; the “2 tools" include nature-inspired education and planning & design. By regulating the soil microecology, the system not only improves soil fertility and crop yield but also reduces the use of chemical fertilizers and pesticides, ensuring the safety of agricultural products and improving the regional ecology. It also brings social and economic benefits such as increasing farmers' income and promoting rural revitalization.

Why we contacted

Understand the pesticide application practices of frontline workers and clarify the project’s advantages.

Interview Content

Promotion methods: The Science and Technology Backyards have developed mature strategies. Before promotion, they conduct large-scale farmer surveys every August; they leverage the strength of “scientific farmers" —— cooperating with cooperative representatives, “farming experts" among farmers, and other locally respected figures - to build a communication bridge with ordinary farmers, facilitating the promotion of new technologies. In previous similar promotion efforts, they have also invited local village leaders to translate dialects and used prizes to attract farmers, narrowing the distance with farmers and laying a foundation of trust for subsequent promotion.

Farmers' awareness: There are differences across different crop cultivation scenarios. In the field of vegetable cultivation, even under the promotion model of the Science and Technology Backyards, farmers still have insufficient awareness of bacterial diseases. When problems arise, they often directly purchase chemical pesticides without paying attention to the type of pathogen. In contrast, in rice-growing areas, after years of work by the Science and Technology Backyards, farmers' acceptance of new technologies has increased, and “scientific farmers" who participate in promotion have emerged, demonstrating a deeper understanding of cultivation techniques.

Why we contacted

Understand the acceptance of new pesticides and learn insights into project implementation.

Interview Content

Regarding the acceptance of pesticides in the agricultural sector: Dr. Zhai stated that the situation is relatively positive, citing examples such as the use of fungal viruses to control chestnut pathogens. However, she emphasized that the key to the implementation of engineered live pesticides lies in their self-limiting properties —— to avoid excessive spread in the environment. She drew a parallel to the sterile design of hybrid rice, which prevents gene diffusion.

Regarding technological R&D and motivation support: In response to the team's question about constructing a T7 phage tail fiber particle library, Dr. Zhai suggested that a large amount of data must first be collected —— similar to the data threshold required for AI modeling —— providing inspiration for the modeling team. Using her own project as an example, she emphasized the importance of focusing on the needs of common diseases and building solid technical reserves. She encouraged the team to face challenges head-on, injecting motivation into the project's advancement. She also reminded the team to respect biological characteristics and balance human factors with the complexity of real-world scenarios.

Why we contacted

Understand how to culture and identify Pst. DC3000.

Interview Content

Since we had no prior experience in culturing Pst. DC3000, we quickly encountered a problem during our first attempt: we could not distinguish Pst. DC3000 from E. coli on ordinary LB agar plates. Additionally, phage infection experiments require pathogenic bacteria to be cultured to the logarithmic growth phase. Therefore, we conducted an interview to learn about the culture conditions for Pseudomonas syringae. Dr. Geng generously provided us with the culture conditions and incubation times for both solid and liquid media commonly used for DC3000, and informed us that using MG medium can inhibit the growth of E. coli. This laid a solid foundation for the smooth progress of our experiments.

Why we contacted

Understand farmers’ true opinions and current level of awareness.

Interview Content

Mr. Fu, a farmer in the North China Plain, owns 12 mu of land - he rents out 5-6 mu and cultivates 6-7 mu himself, mainly growing wheat and corn in rotation. For each crop cycle of wheat and corn, he sprays pesticides 3-4 times, with the dosage adjusted according to the severity of diseases and pests.

Mr. Fu had not heard of biopesticides before the interview, but clearly stated that he would be willing to use new pesticides if they can maintain efficacy, reduce environmental pollution and be safe for humans.

Mr. Fu had heard of the China Agricultural University's Science and Technology Backyards and had participated in training organized by the backyards. He clearly stated that he was willing to follow the pesticide recommendations and technical guidance provided by the backyards, recognizing the professional advice and promotional value of these institutions.

Why we contacted

Evaluate and improve the biosafety of the project.

Interview Content

In terms of plant disease resistance and breeding: Professor Dong pointed out that the core of plant disease resistance follows the “gene-for-gene" theory, but pathogen evolution can weaken this resistance —— a major challenge in breeding. In terms of biosafety: Key concerns include gene flow control, evolutionary pressure on pathogens, and non-target effects. These can be addressed by following the “precautionary principle" through molecular technologies and other means.

For vector construction: Professor Dong suggested using inducible promoters to reduce the metabolic burden on chassis cells. Regarding the design of the Sok system, he warned of the risks of plasmid transfer and off-target effects, proposing optimization solutions such as combining inducible promoters with suicide pathways. The environmental release of engineered phages carries risks of unpredictable ecological impacts. To address this, a suicide switch can be introduced, combined with environmental monitoring.

Why we contacted

Resolve issues encountered by the experimental team, such as phage extraction and toxin plasmid packaging.

Interview Content

Phage technology and modification: Professor Tong pointed out that wild-type phages naturally have higher infection efficiency. T7 phages are selected for their safety and high success rate in tail fiber replacement, but after modification, the specificity and broad-spectrum efficacy of the tail fibers must be verified. The interaction between phages and bacteria occurs in two stages: non-specific adsorption and specific adsorption, with tail fibers playing a key role in the latter. Verification based on protein interaction results is therefore necessary.

Production: Phage formulations must undergo purification. The standards for agricultural use are lower than those for animal use, requiring only the absence of viable bacterial residues. The choice of solvent and formulation requires trade-offs: liquid

formulations can maintain activity but require short-term low-temperature storage; powder formulations are stable at room temperature but may damage tail fibers during the preparation process. To address UV sensitivity, measures such as light-proof storage and shortening field exposure time can be adopted; for replicable phages, activity loss can be compensated by subsequent replication.

Application safety and legal ethics: Professor Tong informed us that there are no special legal or ethical restrictions on the agricultural application of modified phages. The core requirement is to ensure formulation purity, avoiding the inclusion of lysogenic phages (which may enhance bacterial virulence).

Why we contacted

To evaluate our PhAgri-based strategies for achieving the Sustainable Development Goals and to further optimize the project’ s sustainability efforts.

Interview Content

This discussion on biopesticides covered multiple dimensions, including application promotion, sustainable development, and interdisciplinary topics. Biopesticides focus on the control of bacterial diseases - for example, targeting Pseudomonas syringae through the application of synthetic phage particles to soil to reduce pesticide residues. Their promotion aligns with SDG 12 (Responsible Consumption and Production), supports rural economic development, and must address the challenge of increased disease incidence due to climate change.

Our discussion delved deeply into the connection with SDGs. Professor Liu emphasized that project design must balance macro long-term goals, pay attention to scientific ethics and humanities/social sciences, and proposed the three stages of environmental justice (recognition, procedural and distributive justice). Therefore, product design must consider vulnerable groups and environmental impacts to avoid new inequalities.

Why we contacted

Refine the specific form of the product (ingredients, production methods, etc.).

Interview Content

Product formulation and stability: Professor Jiang suggested replacing traditional emulsifiers with soluble liquids (containing xanthan gum + dispersant) to avoid damage to phage structures by oils and emulsifiers. At the same time, xanthan gum can act as a suspending agent. When combined with surfactants such as Tween 80, it can ensure phage activity and meet application requirements. He also recommended referring to foreign patents and domestic formulations of live pesticides to reduce the risks of independent design.

Technology integration and application scenarios: He proposed an integrated solution of “AI identification + phage control + intelligent equipment": using AI to accurately identify leaf diseases (e.g., yellow spot disease), leveraging the rapid action of phages and combining with UAVs to enable automatic disease identification and spraying dosage recommendation. AI identification technology has already been validated in fruit tree disease control.

Why we contacted

Understand the challenges in the implementation of new biopesticides.

Interview Content

Professor Meng recognized the potential market and value of the product, noting that farmers growing cash crops have high requirements for the appearance and quality of agricultural products. If green pesticides can reduce chemical pesticide residues and meet the standards for high-quality agricultural products, they can help farmers increase their income. They can also assist agricultural products in obtaining green labels, breaking through the entry barriers of supermarkets, gaining price premiums and opening up the mid-to-high-end market.

At the same time, Professor Meng emphasized the difficulties of commercialization. Farmers prioritize cost-effectiveness —— if green pesticides are priced higher than traditional chemical pesticides and farmers cannot clearly perceive the income-increasing effects, they will reject them. Farmers also have a strong risk-aversion mindset; their concerns include the application methods of green pesticides, compatibility with existing farming equipment and the stability of efficacy under extreme weather conditions. Additionally, applying for green labels requires meeting multi-dimensional standards throughout the entire production process.

Why we contacted

Understand knowledge related to enterprise transformation and agricultural socialized service systems.

Interview Content

Driving the biological industry chain: Professor Sang pointed out that once new biopesticides gain market traction and achieve scale, they will create a consumer environment with more favorable prices. They may also expand ordering channels through e-commerce platforms, thereby encouraging more people to use biopesticides. This forms a positive cycle of “market driving adoption, and adoption promoting the market", injecting sustained momentum into the development of the biological industry.

Improving employment and rural revitalization: Professor Sang put forward innovative ideas: If biopesticides help farmers grow high value-added agricultural products, making agricultural income comparable to urban wages. This will enhance farmers' professional attachment and reshape the value of rural areas. Rural areas can become urban backyards, ecological barriers, food bases and leisure destinations, forming an urban-rural symbiotic relationship.

In addition, the discussion touched on the multiple impacts of biopesticides on agriculture and the paths for integrating biopesticides into agricultural socialized service systems. It also explored trends such as appropriate agricultural scale expansion during urbanization and urban-rural integration, believing that the project is expected to drive the development of high value-added agriculture and provide solutions for agricultural ecology and rural development.

Why we contacted

Ask questions about the business plan and understand consumer psychology.

Interview Content

Regarding the focus of product promotion: Professor Xu pointed out that although the project aims to enable farmers to produce the product independently to reduce costs, farmers will find it difficult to fully understand the underlying principles. Their core concerns are “pesticide price" and “pesticide efficacy". Therefore, the business plan must move beyond a biological science perspective, target non-professional readers, downplay technical principles, and instead use plain language to highlight product benefit.

Regarding sales models and profit design: Professor Xu suggested balancing farmer support with corporate profitability: providing farmers with discounted semi-finished products and formulation plans to lower their adoption threshold and costs. At the same time, relying on core technologies to independently produce high-priced finished products for large-scale centralized planting enterprises. This builds a dual-track sales model of “farmers + enterprises", achieving multi-faceted economic growth. This also aligns with target market analysis.

Why we contacted

Resolve issues related to the tail fiber evaluation platform.

Interview Content

On September 26th, Professor Yue Feng from Beijing University of Chemical Technology gave a lecture at our university on Bacterial Defense Systems and Phage Counter-Defense Weapons. Through this lecture, we gained a deeper understanding of the activation mechanism of bacterial population immunity and the mechanism by which bacteria attack phage DNA. After the lecture, we were fortunate to have the opportunity to communicate with Professor Feng, and we raised two questions: first, whether our phage-like particle pesticides could avoid being attacked by the defense mechanisms that target phage DNA; and second, whether they could achieve better bactericidal effects by leveraging the bacteria’ s own suicide mechanisms. Professor Feng gave affirmative answers to both questions, stating that such strategies are generally effective based on his research. However, he suggested that we conduct a more detailed investigation into the potential connections between our suicide plasmids and the genome of the target bacteria to determine the specific extent of their impact.

On the 29th, we conducted a further interview with Professor Feng. Our modeling team asked the following question: When using the three models we currently have to comprehensively evaluate the effectiveness and reliability of the replacement, how should we perform a comprehensive analysis by weighting the confidence levels provided by the three models, each responsible for a different part? Professor Feng’ s opinion on this was that he has greater confidence in the confidence results provided by the ESMFold model. At the same time, since users may have different understandings of different confidence levels, he recommended that we allow users to choose the weights independently.

Why we contacted

Understand the practical challenges of African agriculture and the specific operation model of the Science and Technology Backyards.

Interview Content

This interview focused on the application of the new phage pesticide project in Africa, conducted with the practical team of the China-Africa Science and Technology Backyard. First, it was learned that the Science and Technology Backyards promote technology through the “1-3-5-1" on-site residency model, gaining farmers’ recognition through intuitive methods such as demonstration fields, and have obtained support from the Malawian government. However, the high cost of agricultural inputs in Africa and soil adaptability issues are core challenges for technology promotion.

Second, it was found that smallholder farmers in Africa struggle to afford chemical pesticides due to high prices and rely on traditional control methods —— creating opportunities for green pesticides.

Why we contacted

Understand fruit and vegetable vendors’ awareness and management of pesticide residue issues in agricultural products.

Interview Content

From the vendor's perspective, consumers generally hold a contradictory attitude toward pesticide residues —— they actively ask about pesticide use when purchasing, but since residues are unavoidable in agricultural production and no obvious health hazards have occurred, they no longer inquire about specific residue levels. As a vendor, Mrs. Yan indirectly controls pesticide residue risks by selecting suppliers with a good reputation, but due to differences in pesticide use standards across different production areas, she cannot accurately track pesticide residue data for fruits and vegetables. When asked by consumers, she can only respond with vague statements.

After learning about the new phage pesticide, she recognized its characteristics of being “naturally derived, target-specific bactericidal, and easily degradable", believing it meets consumers' expectations for healthy food and has market potential. From the consumer's perspective: Mrs. Yan herself also believes that small amounts of pesticide residues are acceptable. She also mentioned that the declining taste of fruits and vegetables today may be related to the excessive use of pesticides and chemical fertilizers.

In daily life, she mainly uses “running water washing + long-term soaking" to handle pesticide residues but admitted that she is unsure of the actual effectiveness —— this method is more for psychological comfort.

Why we contacted

Understand consumers’ views and demands regarding pesticide residues and biopesticides.

Interview Content

Regarding pesticide residues: Mr. Liu has a clear dislike for chemical pesticides. On one hand, he feels helpless about “knowing there are residues but having to eat them"; on the other hand, he is dissatisfied with some farmers who overuse pesticides to pursue better appearance and higher yields, believing this exacerbates market irregularities.

When dealing with pesticide residues, he has health awareness and purchases commercial “fruit and vegetable cleaners" for washing, but admitted that products on the market vary in quality. He urgently expects relevant state departments to launch official cleaning products with credibility and authoritative certification to ensure effectiveness and safety. Regarding organic vegetables: Although Mr. Liu is concerned about food safety, he holds reservations about “organic vegetables" due to issues such as lax certification and exaggerated promotion in the market, and does not prioritize them when purchasing.

Regarding awareness and acceptance of biopesticides: Mr. Liu had heard of biopesticides before and was aware of their harmless nature. After further introduction to the project, he showed a high level of acceptance toward the new phage pesticide, fully recognizing its safety and market value.