Out of a dozen insect pests, the safflower aphid causes 30 to 80 per cent yield loss based upon weather conditions. Though safflower aphid causes economic damage to the crop, majority of growers seldom use control measures.
The adult aphid is black and shining. With the help of its syringe like proboscis, both nymphs and adults suck the cell sap due to which the plant growth is stunted.
Different seasonsIn case of severe attack, the plants start showing drying symptoms from lower leaves progressing towards the top. In Karnataka, the aphid first appears during first week of November and reaches a peak between end of December and end of January and disappears by the end of March.
In Maharashtra it starts at the end of October and reaches peak by first week of January. However, in Delhi the aphid made its appearance in February and peaked during mid March.
Management strategies— Take up plant protection measures soon after appearance of the aphid.
—Early sowing escapes the peak pest incidence. In Karnataka, October and November sown crop had maximum infestation while, the September sown crop experienced less damage. In Maharashtra, mid September was better for sowing to minimise aphid damage.
— Application of balanced fertilizer is also one of the components in aphid management.
— Higher the nitrogenous fertilizer, more will be the aphid infestation and vice-versa.
—Safflower, intercropped with sorghum, coriander and wheat reduces the pest population. Safflower with coriander not only reduces the aphid population on safflower, but increases the predatory population.
Chemical insecticides
Chemical insecticides are one of the inevitable components in the integrated pest management. Insecticides like thiamethoxam at 0.2gm/l, acetamipirid followed by imidacloprid were found more effective and economical. Among several seed dressers, carbosulfan 25 DS at 20 gm/kg of seed proved effective.
(Dr. D. N. Kambrekar is Scientist (Agricultural Entomology), Regional Agricultural Research Station, UAS Campus, Vijayapur-586 101 (Karnataka), Email: kambrekardn@gmail.com Phone: 08352-230568.)