Biology and Management of Mealy Bug, Drosicha dalbergiae (Stebbing) (Homoptera : Margarodidae) on Almond (Prunus dulcis Mill)

The studies on the “Biology and Management of Mealy Bug, Drosicha dalbergiae (Stebbing) (Homoptera : Margarodidae) on Almond (Prunus dulcis)” were carried out during the year 2007-2008 in the Biological control laboratory, Division of Entomology, SKUAST-K, Shalimar and under field conditions ie. orchard of Horticulture Development Department (J&K Govt.) Zawoora, Khanmoh, Srinagar. The studies on various biological parameters revealed that the pre-oviposition, oviposition, post-oviposition, incubation, 1-5th larval instars, and male/female adult longevity period were 1.40±0.2, 13.0±1.2, 2.50±0.2, 67.3±1.1, 263.0±0.2, 3.9±0.2/16.9±1.6 (M/F) days, respectively. The average fecundity per female was recorded as 122.30±0.6 with the Sex ratio of 1:2 (M: F).The total developmental period (egg to adult) was recorded 349.1± 7.1 days with only one generation per year. The mean pest population of mealy bugs/100 cm2 in rhizosphere and trunk ranged from 19.65 to 47.90 from 9th to 26th standard week and a decline in mean pest population from 43.0 to 26.6 from 27th to 29th standard week was observed, during 2007-2008, respectively. The studies on management of almond mealy bug, D. dalbergiae carried out during 2007-2008 under field conditions revealed that among soil insecticides applied in March, carbaryl (10% dust) showed maximum cumulative mortality per cent of 51.22 followed by chlorpyrifos (10G) to the extent of 47.78 per cent. The order of efficacy with respect to cumulative mean per cent mortality among the foliar insecticides applied at recommended concentrations during the month of May 2007-2008 against mealy bug, D. dalbergiae showed the following trend; methyl-o-demeton (64.08) > dimethoate (56.95) > chlorpyrifos (45.61) > M.anisoplae (17.33) > B.brongniartii (15.32) > B.bassiana (10.99) 30 days after treatment., respectively. The efficacy of soil as well as foliar insectiticides when applied on same plants revealed that the highest mean mortality per cent of 71.13 was obtained when carbaryl (10 % dust) in the month of March followed by dimethoate (0.03%) applied during May 2007-2008.The lowest mean mortality per cent of 44.98 was recorded with B.brongnartii (1x108) and quinalphos (5% dust)