Fungicides: The uncharted domain

Abstract

Fungicides have revolutionized agriculture by reducing crop losses due to diseases. In the early 1800s, plant scientists and chemists began the quest for fungicides, leading to the discovery of lime sulfur and Bordeaux mixture for the control of powdery mildew of fruit trees and downy mildew on grapes respectively and they were grouped as the first-generation fungicides. These inventions raised farmers’ expectations for the next breakthrough in performance.As the damaging effects of crop diseases became evident, research to discover novel active materials accelerated. Prophylactic second generation of fungicides, including dithiocarbamates quinones, captan and chlorothalonil came to the vogue. Subsequently, third generation of systemic fungicides such as 2-aminopyrimidines, benzimidazoles, carboxamides, phenylamides, fosetyl-AI, azoles and related compounds, offered new opportunities in disease control.As new areas of chemistry were introduced, research-based organizations have adopted patent-busting tactics to capitalize on the growing fungicide market. New-generation, highly specific fungicides that target the disease triangle in several ways were anticipated by the researchers and the academia.Besides their therapeutic impact, fungicides can also alter the host’s carbohydrate levels or mimic the host defense mechanism. Boscalid, Metconazole, Fluxapyroxad, Mefenoxam, and Penfluf en are examples of f ungicides available in the global market that pos ses s thes e properties.Triflumizole, Amisulbrom, Cyflufenamid-Valifenalate are anticipated to take centre stage in the f ight against oomycetes due to their low dos es and c apac ity to reduc e the danger of resistance.Another class of fungicides, are non-fungitoxic in vitro but possess a potential to combat plant diseases by impeding the mechanisms which enable fungi to colonise the plant or by enhancing the host plant’s resistance. For instance, probenazole stimulates plant defence systems whereas tricyclazole induces malfunctioning fungal appressoria.Plant pathologists endure significant concerns in fungicide resistance and future potency of chemical disease control relies on continuing to invest heavily in research. Although many disease control issues remain unresolved, toxicological reviews, resistance-marketing requirements place a high priority on the discovery and development of replacement fungicides. The development of fungicides will depend extensively on developments in comparative biochemistry, plant pathogen genetics and epidemiology, as well as computational chemistry.