Plant Health Care Leads the Use of Harpin Peptides in Agriculture

Decades ago, scientists demonstrated that plants, like animals, possess innate immune systems to detect and respond to potential dangers. Plants employ complex signaling networks to communicate the presence of threats throughout the plant, mobilizing defense responses even in unaffected areas, which is defined as Systemic Acquired Resistance.

The challenge in science was how to provide this threat signal to plants, because unlike humans and other animals, plants do not have many of the sensory organs such as eyes, ears, smell, taste, etc. Zhongmin Wei (pictured), during his postdoctoral research at Cornell University, first isolated a protein molecule characterized as a Harpin protein from a plant pathogenic bacterium, Erwinia amylovora. 

Harpin is a signaling molecule that plants detect as a threat, prompting the plant to begin defending itself by activating its innate immune system. The use of proteins or peptides in human health had long been known, but this was the first time anyone had demonstrated their use in agriculture. This discovery was considered so significant that the prestigious journal Science featured it on the cover of its 1992 issue (Science Vol. 257, No. 5066, pp. 85-88). 

Research has demonstrated that when plants are exposed to Harpin protein or peptide derived from Harpin proteins, they activate salicylic acid and jasmonic acid dependent defense pathways that trigger the plant to make changes in cellular structure or release certain unique biomolecules to defend against diseases, pests and nematodes from infecting the plant. 

In addition to defense responses, Harpin proteins are also known for their ability to stimulate plant growth, leading to higher yields and/or improved product quality. Harpin proteins offer broad-spectrum protection against fungal, bacterial, and nematode diseases. 

Innovation and pioneering spirit

Plant Health Care—now part of PI Industries' biological business—is the first company in the world to offer innovative Harpin and peptide technology in agriculture as a more sustainable option for crop protection and yield enhancement compared to traditional chemical pesticides. It is also the only company in the world to offer these products in crops.

Plant Health Care's products based on Harpin and derived peptides are currently sold in more than 25 countries worldwide and have distribution partners and operations in Brazil, Mexico, the US, the UK, Portugal, Spain, Italy, Turkey, and South Africa, with product registration in India expected in 2025. PI Industries acquired Plant Health Care in 2024 as part of its vision to be a leading global biological company. 

How Plant Health Care Peptides Differ from Synthetic Products 

Farmers have used a wide range of agricultural inputs in recent decades, and it's crucial that they have access to a variety of tools to manage their challenges in the field. Highly effective synthetic crop protection products have played a significant role in improving agricultural productivity and are an important tool for farmers. 

However, these products present challenges in terms of resistance development, effects on beneficial microorganisms/insects, residues and environmental impact, and, recently, increasing pressure from regulatory bodies and society to reduce their use.

Traditional biological products, on the other hand, have variable efficacy. The performance of microorganism-based products is affected by various environmental factors and native microorganisms. Managing shelf life, storage, and compatibility of the tank mix with other agricultural inputs are some of the other challenges.

Plant Health Care's peptide-based products are biomolecules and are unaffected by many of the same factors that affect living microorganisms. Plant Health Care's peptides lie between synthetic crop protection products and traditional biological products in terms of efficacy and performance. They have the potential to provide the efficacy of synthetic crop protection products combined with the beneficial environmental properties of biological products.

Plant Health Care peptides work in a wide range of environments, are compatible with a variety of agricultural inputs, have a long shelf life, and have no residues or impact on beneficial microbes/insects. Plant Health Care peptides activate the plant's innate immune system to protect it against biological and abiotic stress. They do not directly kill microorganisms or plants, and therefore, there is no risk of developing resistance.

Plant Health Care currently has the world's largest library of peptide molecules for agricultural product development, and approximately 700 peptides have already been cataloged for use in agriculture to treat plant diseases, manage nematodes, manage abiotic stress, improve yield, and stimulate plant growth. 

To date, three of these peptides have been approved and commercialized globally, and another 12 are in the testing phase, offering various benefits to farmers. With the investment from PI Industries, Plant Health Care is expanding its research team and programs, and new peptides are being created for the development of new products. Given the importance and uniqueness of peptides, many companies are currently investing in research to bring peptide-based products to market, but Plant Health Care, with over 30 years of experience in this field, has a clear lead. 

To achieve its vision of becoming a leading global biologics company, PI Industries has invested in four R&D facilities in the US and India dedicated to research into biologics solutions. 

Coplacana is the leading distributor of Plant Health Care in Brazil, offering PHC's unique technologies to sugarcane producers for the past seven years. Today, hundreds of thousands of hectares of sugarcane in Brazil benefit from the Harpin peptide solution.

By Jagresh Rana, Global Head of Biologicals, Plant Health Care