Pear gall midge

Systematic position. The pear gall midge (Inostemma piricola) belongs to the order Hymenoptera, specifically the family Platygastridae. It is a specialized pest that causes significant economic losses in pear production by directly impacting fruit development at the embryonic stage.

Host crops and damage. The primary host is the pear tree. The larvae specifically target the fruitlets. The economic impact is high because damaged fruits are generally unsuitable for market, and in severe infestations, a large proportion of the total seasonal yield can be discarded by the tree as fallen fruit.

Biology and life cycle. The life cycle is synchronized with the phenology of the pear tree. Adult wasps emerge during the budding and flowering phase. After mating, females oviposit inside the developing fruitlets. The larvae develop inside the fruit, causing characteristic physiological changes, and then descend to the soil to pupate and overwinter.

Character of damage. Infested fruitlets show abnormal growth patterns. Initially, they may grow faster than healthy fruit, leading to a swollen, deformed appearance. Eventually, the internal tissue is consumed, causing the fruit to blacken, wither, and prematurely drop. The presence of larval chambers inside the fruit is a diagnostic sign.

Control measures. Integrated Pest Management (IPM) is essential for controlling this pest. Sanitation measures, such as the rapid removal and destruction of fallen fruit, are crucial to prevent larvae from entering the soil. Soil cultivation around the base of the trees helps disrupt the pupal stage. Insecticide applications should be timed carefully during the pre-bloom or bloom period based on field monitoring data.