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Basics of Entomology

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History of Entomology in India

HISTORY OF ENTOMOLOGY IN INDIA Ancient Indian: • Honey has been known to us from pre-historic times. Honey finds mention in the Vedas, the Ramayana, the quran and many ancient books. Rigvedas mentions honey as the choist food of god (3000-5000 B.C) • Atharva veda gives a brief account of Lac, the lac insects and usefulness values of lac . In Mahabharata, there is a reference of Laksha Griha i.e , a house of lac implies that lac had been cultivated in India from pre-historic times. • Silk production is believed to have originated in China nearly 5000 years ago and slowly spread to India. An Indian prince sends a gift of silk cloth to a Persian ruler in 3870 B.C, indicating that Indians were familiar with the rearing of silkworm. • In ancient scripts like Ramayana and Mahabharata, some of the terms used were related to insects. They are Pipilika – Ant, Pathanga – grasshoppers, Madhumakshika – honey bees, Umbakapalika ...
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Inorganics and Botanical Insecticide

INORGANIC INSECTICIDES Arsenic compounds: In an arsenical compound, the total arsenic content and the water soluble arsenic content are of importance, the water solubility of arsenic may result in entering the foliage and causing burning injury to plants, and hence water insoluble compounds are preferred for insect control. Arsenates are more stable and safe for application on plants then arsenites. Arsenites are mainly used in poison baits since they are phytotoxic. However arsenates are less toxic to insects then arsenites. In insects arsenates cause regurgitation, torpor (sluggishness) and quiescence. Disintegration of epithelial cells of the midgut and clumping of the chromatin of the nuclei are the effects noticed in poisoned insects. Slow decrease in oxygen consumption is also evident and kill of the insect is primarily due to the inhibition of respiratory enzymes. Water soluble arsenic causes wilting followed by browning and shriveling of the tissue. 1. Calcium arsenat...
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BIOLOGICAL CONTROL

BIOLOGICAL CONTROL The successful management of a pest by means of another living organism (parasitoids, predators and pathogens) that is encouraged and disseminated by man is called biological control. In such programme the natural enemies are introduced, encouraged, multiplied by artificial means and disseminated by man with his own efforts instead of leaving it to nature. The term biological control was first used by Smith in 1919 to signify the use of natural enemies to control insect pests. Natural Control: The maintainance of population numbers within certain upper and lower limits by the action of a combination of abiotic and biotic factors as well as the characteristic of the species under consideration is called natural control. History and development of biological control and classical examples of biological control First use of insect predators was in 900AD, when Chinese citrus growers used red ant ( Oecophylla   smaragdina ) on the citrus trees to contro...
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