The aim of this work was to determine the influence of the host plant, as food, on the larval and adult phases of D. speciosa. Larvae of this insect were reared on seedlings of bean, corn, soybean, as well as on potato tubers kept in wet vermiculite. The following biological parameters were evaluated: duration and viability of the larva-adult period and the weight of newly emerged insects (males and females). The fecundity of D. speciosa was also evaluated offering to the adults leaves of bean, soybean, corn and potato. The host plant offered as food on the larval phase influenced significantly the weight of the insects (males and females) as well as the duration and viability of the larva-adult period. The development time of the immature phases (larva + pupa) on potato (36.5 days) was longer than that on corn (25.1 days). The viability values (larva + pupa) were higher on potato (84.1%) and corn (75.9%) while on soybean and bean the viability was low (30.1% and 9.4%, respectively), characterizing these plants as inadequate hosts for the larval development of the insect. Adults of D. speciosa fed on potato and bean leaves presented fecundity significantly superior to that on soybean or corn leaves. Therefore, corn seedlings and potato tubers are appropriate to larval development of D. speciosa, while leaves of potato and bean are suitable for adults.
insecta; corn rootworm; host plant; survival; fecundity
