Fungicides belong to a range of essential crop protectant tools that also include insecticides and herbicides.
Fungicides can be classified as contact or systemic. Contact fungicides remain on the plant’s surface and are also referred to as protectant or preventative fungicides. Systemic fungicides are absorbed and move variable distances within a plant, they are also known as preventative or curative fungicides. All fungicides are more precisely classified by their mode of action.
Up until the 1940s, disease control relied upon inorganic formulations frequently prepared by farmers. Synthetic chemicals were developed by agrochemical companies after World War II, many were systemic fungicides. Their advantages included reducing application rate, improving selectivity and reducing phytotoxicity. Widespread use of these new fungicides, together with fertilisers, agricultural mechanisation and improved plant genetics, contributed to the success of the Green Revolution.
Since the 1970s global agrochemical companies have continued to invest large sums of money in discovering and developing new crop protectants that are more selective for disease, weed and insect control – using a range of modes of action – and possess reduced toxicity profiles and lower environmental impacts. Nonetheless, this task is becoming increasingly challenging, time-consuming and costly.
Paradoxically, as these improvements have ensued for crop protectants, selection pressure through their application has been placed on weeds, pests and diseases and they are developing resistance. Integrated methods of management are endorsed, with protectants as one component.
Australian growers require the latest crop protection products and technologies to support robust, sustainable and globally competitive grain production. However, access to these protectants can at times be restrictive as the Australian market is small compared to international markets.
Combined, these issues mean the Australian industry needs to adopt best stewardship practices. Through collaboration, engagement and support by all stakeholders, responsible and sustainable use of crop protectants, including fungicides will be ensured to prolong their longevity.