Green Agrochemicals: Pesticides, Fertilisers and Biopesticides

Global agriculture relies on chemical inputs to feed 8 billion people, yet this has caused environmental degradation, biodiversity loss, and insect resistance. This chapter explores the chemistry, processes, and sustainability of conventional synthetic pesticides, green and biological fertilizers, and biopesticides. Synthetic pesticides including organophosphates, carbamates, pyrethroids, and neonicotinoids, their environmental persistence, toxicities, and ecological impact are covered. Then it compares these to biopesticides, which the EPA describes as pesticides made from animals, plants, microorganisms, and minerals. Microbial pesticides, biochemical pesticides (including semiochemicals and plant extracts), and plant-incorporated protectants are biopesticides. The chapter examines how Bacillus thuringiensis, fungal entomopathogens, and entomopathogenic nematodes suppress pest populations with high target selectivity and little non-target harm. Semiochemical synthesis, especially olefin metathesis pheromone generation, is explored as a green chemistry pest management model. The chapter discusses green and biological fertilizers, focusing on nutrient recovery from agri-food waste to implement circular economy ideas. Advanced formulations, such as nano-biopesticides, increase delivery precision and shelf stability while raising ecotoxicological concerns. Regulatory regimes in the EU and US are assessed, with a focus on the EU Farm to Fork Strategy's 50% chemical pesticide reduction by 2030.