A review of castor-derived products used in crop and seed protection

Castor-derived products are currently used for protecting agricultural crops and seeds from devastating damages of pests and diseases. Extracts (1–10%) of leaf or seed in water or chemical solvents, and crude oil (3–5%) extracted from seed were found effective as sprays against foliage insect pests. Populations of the root-knot nematodes were significantly reduced when de-oiled seed cake was incorporated into soil at 1000 kg/ha, especially after mixing it with bio-inoculants such as, a fungus (Poecilomyces lilacinus) or a bacterium (Pasteuria penetrans). Castor proved as a potential synergist when mixed with other plant products or chemical pesticides and exhibited different modes of actions but with comparatively limited insecticidal properties. In less developed and developing countries, the common use of oil is for treating stored cereals and pulses at 5–10 ml/kg seed. In both field and greenhouse experiments, pest mortality and other biological parameters were dose-dependent. This review discusses different uses of castor products to foresee possibility of replacing or at least reducing use of toxic chemicals in crop and seed protection.