FIELD EVALUATIONS OF PARASITOIDS OF LARVAL STALKBORERS AGAINST EOREUMA-LOFTINI (LEPIDOPTERA, PYRALIDAE) IN RICE

Five species of parasitoids of larval stalkborer were evaluated in Tex as in 1987 against the Mexican rice borer, Eoreuma loftini (Dyar), in field enclosures in rice, Oryza sativa L. The braconids, Alabagrus sti gma (Brulle) and Allorhogas pyralophagus Marsh, and the bethylid, Goni ozus natalensis Gordh, each parasitized >5% of the available E. loftin i. The braconids, Apanteles minator Muesebeck and Macrocentrus prolifi cus Wharton, parasitized <1% of the available hosts. Allorhogas pyralo phagus parasitized the highest percentage of borers, including 65.6% o f the fifth- and sixth-instar E. loftini. Alabagrus stigma and G. nata lensis parasitized fewer borers overall, although parasitism by A. sti gma averaged 21.2% of small E. loftini in the rice leafsheaths. Alabag rus stigma, A. pyralophagus, and G. natalensis are candidates for furt her evaluation in the event that E. loftini becomes a pest of rice in Texas.