Identification, live cycle and distributions of pine woolly adelgide on pinus plantations in Java Island

Abstract

Pine Woolly Adelgide (PWA), is a newly-found exotic pests, in P. merkusii plantations in Java Island, causing dieback or abnormality of the plants, dried and defoliated branches, and eventually killed the trees. A study was conducted to identified the species of this exotic pest and detrmined its life cycle, as well as geographics distribution. Based on the specific characters of PWA, the insect was identified as Pineus boerneri Annand (Hemiptera; Adelgidae). Abdomen spiracles consisted of four pairs. Wax gland was spread all over the body. The spread was regular at the body, while at the head was irregular. Significantly different measurement of each morphological character observed was found in specimens from different KPH indicating high diversity of the insect despite of its parthenogenetic regeneration. PWA had six stadia of development, which totally lasted for 24,5 ± 1,79 days. The whole cycle was shorter than its original cycle in temperate zone. Shorter life cycle indicates rapid regeneration and multiplication ability that this new pest has a potential for invasiveness. The occurrence of PWA was found concentrated in specific location of host plant area. The pest attacks pine plantation on the high altitude > 900 m above sea level, having temperature between 16-200C, and humidity 80-90%. The intensity of the attack was correlated clearly to temperature and altitude of the host plant location. Percentage of attack ranged from 15-100%. The PWA could attack pine in all ages of development. The fast distribution of attacks and rather narrow range of climatic requirement of the pest posted special call for careful silvicultural consideration for new pine plantation establishment, especially in Java. Recently pine is considered as promising fast growing species for plantation in Java with newly introduced moratorium policy, because pine can give other non-timber forest products, such as gum for terpentine.