Late blight, caused by the pathogen Phytophthora infestans, is a significant disease affecting tomato crops globally. This disease can lead to substantial yield losses, sometimes up to 100% under favorable conditions (Kesho Sako & Tadesse, 2023; Mazumdar et al. 2021).
Late blight is characterized by small, dark lesions on leaves, stems, and fruits, which become water-soaked and chlorotic, eventually leading to necrosis. The pathogen infects the entire plant, making it particularly challenging to manage (Mazumdar et al. 2021).
The development of late blight is influenced by environmental conditions such as humidity and temperature, as well as farming practices like monoculture and the use of susceptible cultivars (Kesho Sako & Tadesse, 2023). The pathogen’s ability to rapidly evolve and overcome host resistance further complicates control efforts (Mazumdar et al. 2021).
Effective management of late blight involves integrating resistant tomato varieties with appropriate fungicide applications. Ongoing research aims to develop integrated disease management (IDM) strategies with minimal chemical inputs (Kesho Sako & Tadesse, 2023).
There is a need for further understanding of the molecular interactions between P. infestans and tomato plants to develop more effective resistance strategies (Mazumdar et al. 2021). Additionally, improving research-extension-farmer linkages is crucial for the successful transfer of crop protection technologies (Kesho Sako & Tadesse, 2023).
Late blight remains a major threat to tomato production globally. Continued research and development of sustainable management practices are essential to mitigate their impact on tomato crops (Kesho Sako & Tadesse, 2023; Mazumdar et al. 2021).
The use of copper as a fungicide
While copper (Cu) compounds have revolutionized crop protection, their continuous and frequent use has raised concerns about the long-term sustainability. This is due to the impact of Cu-based compounds on factors such as soil fertility and groundwater, resulting from Cu accumulation over time due to intensive use (Lamichhane et al., 2018). Furthermore, the application of these products, such as copper sulphate and copper nitrate, or spraying highly acidic solutions (pH below 5.5), can result in phytotoxicity (Behlau et al. 2017). Due to many constraints of different Cu-based formulations, the use of less soluble types of Cu, such as copper hydroxide and copper oxychloride, is encouraged.
COPRWET™ tackles tomato late blight
COPRWET™ is a suspension concentrate and contact fungicide containing 300g/L copper oxychloride as its active ingredient.
Copper oxychloride slowly releases copper ions, which are toxic to fungi and bacteria. The copper ions disrupt essential cellular processes in pathogens, inhibiting spore germination and fungal growth.
What distinguishes COPRWET™ as a fungicide?
- Contains 40-60% less copper than alternative copper products but still delivers the same efficacy.
- Stable and flowable formulation.
- Contains OROWET®TECH within the formulation – no additional adjuvant necessary.
- The added benefit of containing OROWET®TECH includes:
-
Formation of an optimal protective film
-
Optimal adherence to plant surfaces
-
Excellent coverage
-
A reservoir of copper ions
-
Controlled release of copper ions over time
-
COPRWET™ acts on the surface of plants, preventing infection rather than curing an existing disease. In two different trials targeting the control of late blight on tomatoes, COPRWET™ demonstrated effective control compared to the untreated control and performed on par with industry standards commonly used in prevention programs, but with significantly less copper.
COPRWET™ offers growers a copper-containing fungicide with superior spreading ability, ensuring excellent coverage of treated plant surfaces for the control of various plant diseases. It achieves high and long-lasting levels of disease control at lower rates of copper per hectare than competitive products, limiting environmental impact and improving sustainability.
References
Behlau F., Scandelai L.H.M., da Silva Junior G.J. & Lanza F.E. 2017. Soluble and insoluble copper formulations and metallic copper rate for control of citrus canker on sweet orange trees. Crop Protection 94:185–191. Available from: https://doi.org/10.1016/j.cropro.2017.01.003
Kesho Sako, A., & Tadesse Demissie, Y. (2023). Overview of Management Practices of Tomato Late Blight (Phytophthora infestans Mont.) Disease. International Journal of Research in Agricultural Sciences. Available at:http://ijras.org/administrator/components/comjresearch/files/publications/IJRAS1106_FINAL.pdf
Lamichhane, J.R., Osdaghi, E., Behlau, F., Köhl, J., Jones, J.B. & Aubertot, J.N. 2018. Thirteen decades of antimicrobial copper compounds applied in agriculture. A review. Agronomy for Sustainable Development 38(28). Available from: https://doi.org/10.1007/s13593-018-0503-9
Mazumdar, P., Singh, P., Kethiravan, D., Ramathani, I., & Ramakrishnan, N. (2021). Late blight in tomato: insights into the pathogenesis of the aggressive pathogen Phytophthora infestans and future research priorities. Planta. Available at: https://link.springer.com/article/10.1007/s00425-021-03636-x
