Comparative study of major biological aspects; duration, feeding capacity, longevity and fecunlity of the two common
coccinellid species; Coccinella undecimpunctata L. and 1-lippodainia convergens Guer., when fed on the cowpea aphid
species, Aphis craccivora Koch. was carried out under laboratory conditions. Total larval durations of
C. undeciinpunctata were 13.6±0.08, 13.02±0.12, 11.2±0.12 and 10.18±0.09 days and those of H. convergens were
12.9 1±0.17, 12.04±0.16, 10.78±0.21 and 8.84±0.26 days, when they were fed on 1st, 2, 3fl and 4th nymphal instars of
A. craccivora, respectively. Feeding capacity of the larval stage of C. undecimpunctata was; 1440.68±12.17,
1149.36±9.65, 809.65±6.68 and 661.14±4.74 nymphs while that of H. convergens was; 1107.43±9.61, 786.33±8.60,
533.20±5.65 and 370.25±3.79 nymphs, when larva of each species was fed on each of the four nymphal instars of A.
craccivora, respectively. Total feeding capacity of the two predatory adults was the highest during the ovipositonal
period; it ranged between 207 — 263 nymphs/adultlday. Females longevity averaged 78.05±2.26 and 48.80±1.66 days
for C. undeciinpunctata and II. convergens, respectively. When adults of C. undecimpuiiciata and H. con vergens were
fed on A. craccivora nymphs, a single mated female deposited 880.85 (742-983) and 729 (589-85 1) eggs from which
hatchability percentages were 81 and 94%, respectively.
Key Words: Biological aspects, Coccinelia undecimpunctata, Hippodanzia convergeas, Aphis craccivora,
laboratory conditions. .
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