The Use of Plant Extracts Against Straw Cereals Diseases
Straw cereals plants are constantly exposed and threatened to many pathogens throughout the growing season that affect their development, yield capacity and quality. The most used method of controlling cereal pathogens is the application of fungicides. However, pathogens have been observed to develop resistance to active substances contained in plant protection products. To reduce the use of conventional crop protection products and improve food and feed safety, there is increasing interest in the use of natural, more environmentally friendly plant-based compounds (i.e. botanicals) to control fungal diseases. Those are derived from plants belonging to different families and are either used as plant extracts, essential oils or both. Plant extracts are effective bioagents against a wide range of plant pathogens, i.e. fungal, bacterial and viral pathogens. Oils obtained from plant seeds have also been used to control plant pathogens. Globally, there are approximately 2500 species from 235 plant families that are effective in controlling diseases and pests. Botanicals based on preparations from medicinal and aromatic plants have high potential for the control of various fungal pathogens. Frequent examples include garlic (Allium sativum), caraway (Carum carvi), fern tree (Jacaranda mimosifolia), rosemary (Rosmarinus officinalis), sage (Salvia fruticosa), thyme (Thymus vulgaris), neem (Azadirachta indica), eucalyptus (Eucalyptus globolus), bojho (Acorus calamus) and asuro (Justicia adhatoda) against fungal pathogens from the genera Aspergillus, Alternaria, Cladosporium, Fusarium, Bipolaris, Penicillium and Puccinia.