Post Embryonic Changes in the Eye of an Economic Mango Plant Pest Amritodus atkinsoni Leth. (Hemiptera: Membracoidea: Cicadellidae)

Abstract

Mango hopper, Amritodus atkinsoni is a serious pest of mango, which may cause up to 50 % crop loss in cases of severe infestation. It leads to large economic loss, as mango is of great economic importance. Amritodus atkinsoni possess two compound eye on either side of the head. Eye plays an important role in the growth and development of the organism. It helps in locating of food as well as partner for mating. Compound eye is known as matching eye to the environment, which undergoes modification with habitat. During the time of development from nymph to adult, remarkable changes are seen in the pattern of food intake and habitat. Young ones of this species prefer feeding on sap of leaves and fruits compared to the adults, which are seen on the barks. Taking this idea we checked for changes in the eye at various developmental stages. The pattern of structural change was examined under scanning electron microscope (SEM). Under SEM the eye possesses numerous functional units called ommatidia and occasionally corneal hairs are present in the eye. At higher magnification the cornea appears rough. More importantly with the increase of age the body length increases which is correlated with the eye size. The functional units, or the ommatidia also change with the size of the animal. With the change in eye size probably the sensitivity changes and thus make the animal more sensitive towards light resulting the change of habitat with age.