G. it. Ent., 6 (31): 151-155
August 31, 1992
Reproductive strategy and sex ratio of the stink bug parasitoid,
Psix striaticeps (Dodd) (Hym.: Scelionidae)
in the Tasar ecosystem
by
R. N. SINGH, K. THANGAVELU, P. K. MISHRA, JAYANT JAYASWAL
Abstract - The study of the oviposition sequence of Psix striaticeps (Dodd), a scelionid egg parasitoid of the stink bug, Canthecona furcellata Wolff (Hemiptera: Pentatomidae) indicates that the male offspring is laid first. The progeny of P. striaticeps ranged from 30 to 45 individuals per female. The predominance of females over males was observed with all the offered egg masses except smaller ones (10 eggs), which were collected from the field. The mean percentage of females was 67% (P = 0.67), which significantly [P = 0.001 (χ2 test)] deviates from an expected sex ratio of 50:50 (P = 0.50). The sex ratio exhibited seasonal variation. The role of P. striaticeps in the biological control of C. furcellata is discussed.
