Life Cycle of White Grub
It is a polyphagous insect pest, mainly infesting the field crops such as sugarcane and groundnut. There are two species in white grub i.e Holotrichia consanguinea and Holotrichia serrata that infest major crops namely, sugarcane, coconut, areca nut, tobacco, potato, and other oilseeds, pulses and vegetable, etc._x000D_ • The white grub, Holotrichia consanguinea completes its life cycle in 76-96 days._x000D_ • The egg period is 8-10 days, larval period is 56-70 days and pupal period is 12-16 days whereas, H. serrata completes its life cycle in 141-228 days wherein, the egg, larval and pupal periods are, 10-12, 121-202 and 10-14 days, respectively. _x000D_ • The grubs are active in their second, third and fourth instar larval stages during rainy seasons (July-October) and feed on organic matter until they come in contact with living roots of plants. Eggs are white and round in shape. _x000D_ • The young grubs are white translucent. Whereas mature grubs are pale in colour and ‘C’ or semi-circular shaped. Before pupation the grub ceases to feed and descends down in the soil to the depth of 40-70 cm. _x000D_ • A short pre-pupal period is spent preparing an earthen chamber for pupation. _x000D_ • The beetles remain in the soil in inactive state at a depth of about one meter till the next monsoon rains. Because of this it also known as June beetle._x000D_ • All the species of white grubs attack groundnut have single generation per year with an active larval diapauses stage._x000D_ Management:_x000D_ • Take up deep summer ploughing to expose the pupae to scorching sun radiation and predation by birds. _x000D_ • Use well decomposed organic manures._x000D_ • Crop rotation with sorghum and pearl millet._x000D_ • Place light traps @ 1 trap/ha between 7PM to 10PM after receipt of first monsoon rains._x000D_ _x000D_ Source: ICAR-DIRECTORATE OF GROUNDNUT RESEARCH_x000D_ _x000D_ If you find this information useful, Like and Share it with your farmer friends._x000D_
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