Effect of wild flowers on oviposition of Hippodamia variegata (Coleoptera: Coccinellidae) in the laboratory.
Marginal vegetation in crops is very important for natural enemies and their pest control capacity. The effects of Brassica nigra L. (Brassicaceae), Daucus carota L. (Apiaceae), and Sonchus oleraceous L. (Asteraceae) flowers as supplemental food on the number of eggs laid during 7 d and on the preoviposition time in Hippodamia variegata (Goeze, 1777) were studied in the laboratory under conditions of several densities of Acyrthosiphon pisum (Harris, 1776). The results show the presence of flowers of Brassica and Sonchus increased egg production 1.44X and doubled the pre-oviposition period (2.13X). This suggests that the availability of flowers of Brassica and Sonchus as supplemental foods (pollen and nectar) in the marginal vegetation of crops can serve to improve reproductive performance of H. variegata, specifically under conditions of prey limitation. Thus, the increase in fitness of this predator allows a better response to changes in pest density.
Bertolaccini
Isabel
I
Departamento de Producción Vegetal, Universidad Nacional del Litoral, Facultad de Ciencias Agrarias. R. P. Kreder, 2805, 3080 Esperanza, Santa Fe, Argentina. isabelb@fca.unl.edu.ar
Núñez-Pérez
Etelvina
E
Tizado
Emilio Jorge
EJ
D000818:Animals; D001517:Coleoptera / Q000502:physiology*; D018552:Daucus carota; D005247:Feeding Behavior; D005298:Fertility; D035264:Flowers; D009149:Mustard Plant; D010058:Oviposition; D011156:Population Density; D031184:Sonchus; D013045:Species Specificity