FIRST REPORT ON SPROUTED POTATO MEDIATED REARING OF MANGO MEALY BUG Drosicha mangiferae (GREEN) TO STUDY BIOLOGY AND MORPHOMETRY

Sprouted potatoes were used for rearing of mango mealy bug, Drosicha mangiferae (Green). Newly emerged 1st instar nymphs were inoculated in the sprouted potatoes and then reared up to adulthood. The duration of each life cycle stages were calculated by keeping close watch on timings of each molting by locating shed exuviae. The total life cycle periods of female and male was different. Females completed the its life span in 121.65±9.32 days whereas in male a little shorter duration of 111.4±11.96 days was required for the completion of life cycle. The life cycle of this mango mealy bug became complicated due to the presence of egg diapause which lasted for almost six months starting from May (last week) to January (1st week) of the next year. Both male and female developed in the same manner till the development of 3rd instar but thereafter due to an intervening pupal stage in the male developmental pattern became different in both sexes. The longevity of female adult was found to be much higher (34.1 & 40 days) than male adults (16.1 &15 days) in two years of study. Till the development of 3rd instar, morphometric measurents of male and female instars were 1st instar, 1.586±0.078 × 0.792±0.031 mm, 2nd instar, 4.82±0.081 × 2.77±0.064 mm, 3rd instar 16.32±0.50×6.82±0.66 mm respectively. Pupa measured 18.2±0.78 x 8.19±0.14 mm. A distinct sexual dimorphism was noticed. The adult females were white and wingless. On the contrary, males were crimson colored having brownish black forewings. Female adults achieved highest mean length × breadth with a measurement of 23.8±1.75×8.4 ± 0.115 mm and males grew upto 10.54±0.36×4.14±0.052 mm. The sex ratio was inclined towards female as 0.475:1 (male: female). This study was undertaken to establish life cycle parameters of the pest which will help pest managers and farmers to formulate control strategies much ahead of the pest attack.