ABSTRACT
Several laboratory and field studies were conducted to broaden our knowledge of the biological and behavioral attributes of Trichogrammatoidea bactrae, a newly imported egg parasitoid of pink bollworm, Pectinophora gossypiella. Immature developmental times ranged from 11 d to just over 7 d at mean temperatures of 22.5 and 29.5 C, respectively. Development was delayed under fluctuating temperatures with maximums > 33.5 C. Survivorship was high under all but the 25/40 C regime. Mean female longevity ranged from 138 h at a constant 15 C to 1.5 h at 40 C. Mean fecundity peaked at 25 C, but females maintained modest fecundity at temperatures between 30-35 C. The majority of eggs laid in the first 24 h of adult life are laid in the first 2-4 h and over 90% are laid within 12 h. Individual oviposition episodes lasted an average of 292 s on Trichoplusia ni eggs and 90 s on pink bollworm eggs. Females were unreceptive in bioassays using surface washes of pink bollworm eggs, but increasingly receptive to untreated spherical beads of progressively larger size. Parasitoids attacked host eggs placed at different levels in the cotton canopy and on leaves and bolls with equal efficiency.
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