The Biology, ecology and natural enemies of the leafminer, Aproarema modicella Deventer (Lepidoptera: Gelechiidae) on groundnut, Arachis hypogaea Linn
by Songyot Phisitkul
- Los Baños, Laguna : Cavite State University- Main Campus, 1985.
- 139 pages : illustrations ; 28 cm.
Thesis (Ph.D. - - Entomology) University of the Philippines, College, Laguna.
Includes bibliographical references.
SONGYOT PHISITKUL, University of the Philippines at Los Banos, July 1985. The Biology, Ecology and Natural Enemies of the Leafminer, Aproaerema modicella Deventer Retainer, Sproaerema modicella Deventer (Lepidoptera: Gelechiidae) on Groundnut, ‘Arachis hypogaea lepidoptera: Gelec of) on Groundnut, ‘Arachis hypogaea Linn, Major Adviser: Dr. Eliseo P. Cadapan
The groundnut leafminer completed its life cycle in 24-33 days. Eggs were laid on the lower leaf surface of the host plant and usually hatched in three days. Newly emerged larvae constructed mines in the leaves and continuously fed inside until they developed into the 4th instar larvae. However, the 3rd instar larvae were the most destructive. Pupal stage was spent within the leaves for about 3-4 days. Adults emerged in the evening with males coming out first. Mating occurred early in the morning and was preceded by a simple courtShip. Oviposition took place in the evening about 10-14 hours after mating. More eggs were laid during the 2nd day. Position but gradually declined in succeeding days.
The rate of insect development was affected by temperature and the kind of host plant. Development was faster as temperature increased from 25°C to 30°C. Moreover, temperature had a greater effect on longevity of adults than food, Insects reared on soybean had a shorter life cycle (21, 10 days) than those on groundnut (23. 73 days) and pigeon pea (25.14 days).
Of the 13 leguminous plants tested, the leaves of soybean and groundnut were highly preferred as food by the larvae.
Both plants received the highest damage rating and contained the greatest number of larvae that mined into the leaves. These plants were also preferred by the adults for oviposition.
RCM 387 and KAC 51 gave the highest yield and correspondingly low infestation compared to other 14 groundnut varieties. Preferred plants had erect growth habit, large leaves and less leaf trichomes. Non-preferred varieties were of the semi-branched and runner types, which had rough, small leaves with more trichomes.
Groundnut planted during the early rainy season produced higher yields than those planted late in season. Early planting escaped high infestation of leafminer in the field. Late infestation was tolerated by the plant. A. modicella was observed in the five groundnut growing areas of Northeast Thailand. Infestation was high in KKU, relatively low in Thapra, Kalasin and Roi-Ait and was very low in Mahasarakam. The most common larval parasites encountered were Tetrastichus sp. and A panteles sp., while the pupal parasites were Brachymeria minuta and B. lasus. However, as a whole, parasitism was low.