5 research outputs found
Suitability of leguminous cover crop pollens as food source for the green lacewing Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae).
Diversification of crops with species that provide suitable pollen for predators may reduce pest population on crops by enhancing predator effectiveness. In this paper we evaluated the suitability of leguminous cover crop pollens to the predatory green lacewing Chrysoperla externa (Hagen). The predator is commonly found in coffee agroecosystems and the plant species tested were pigeon pea and sunn hemp, which are used in organic coffee systems. Newly emerged females and males of C. externa were reared on diets containing pollen of pigeon pea, sunn hemp, or castor bean, used as a control. The reproductive success of C. externa was evaluated when females fed the pollen species and when honey was added to the diets, to verify the predator need for an extra carbohydrate source. Similar intrinsic growth rates were found for females fed on pigeon pea pollen and on sunn hemp pollen but these rates increased significantly when honey was added to the diets. Females fed with pigeon pea pollen plus honey and with sunn hemp pollen plus honey had higher intrinsic growth rates than those fed with castor bean pollen plus honey. Females fed on castor bean pollen only or on honey only, did not oviposit. Leguminous pollen species were equally suitable for C. externa especially when they were complemented with honey. The results suggest that to successfully enhance predator effectiveness, organic coffee plantation should be diversified with plant providing pollen in combination with plant providing nectar
Suitability of Leguminous Cover Crop Pollens as Food Source for the
Adequação do Pólen de Leguminosas Utilizadas em Adubação Verde como Fonte de Alimento para Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) RESUMO ABSTRACT -Diversification of crops with species that provide suitable pollen for predators may reduce pest population on crops by enhancing predator effectiveness. In this paper we evaluated the suitability of leguminous cover crop pollens to the predatory green lacewing Chrysoperla externa (Hagen). The predator is commonly found in coffee agroecosystems and the plant species tested were pigeon pea and sunn hemp, which are used in organic coffee systems. Newly emerged females and males of C. externa were reared on diets containing pollen of pigeon pea, sunn hemp, or castor bean, used as a control. The reproductive success of C. externa was evaluated when females fed the pollen species and when honey was added to the diets, to verify the predator need for an extra carbohydrate source. Similar intrinsic growth rates were found for females fed on pigeon pea pollen and on sunn hemp pollen but these rates increased significantly when honey was added to the diets. Females fed with pigeon pea pollen plus honey and with sunn hemp pollen plus honey had higher intrinsic growth rates than those fed with castor bean pollen plus honey. Females fed on castor bean pollen only or on honey only, did not oviposit. Leguminous pollen species were equally suitable for C. externa especially when they were complemented with honey. The results suggest that to successfully enhance predator effectiveness, organic coffee plantation should be diversified with plant providing pollen in combination with plant providing nectar
Effect of honey feeding by Thyrinteina arnobia males and females on their reproduction and longevity
Nutrients obtained during the larval period can be sufficient for reproduction, but adult feeding may be necessary to reproductive maturity and ripening of eggs. Adult food requirements of Thyrinteina arnobia (Stoll) (Lepidoptera: Geometridae), the main defoliator of eu-
calyptus in Brazil, may present problems in the laboratory. The fecundity and longevity of T. arnobia adults fed on 15% honey solution were evaluated. This solution did not improve the reproductive capacity and longevity of T. arnobia females but it favors those of males,
which could increase mating probability. This is important because T. arnobia males emerge sooner than females, and feeding them could increase their longevity and chances of mating various females