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The parasitization behaviour of Chelonus oculator (F.), egg-larval parasitoid of noctuid lepidopteran species, has been studied under laboratory conditions, using Ephestia kuehniella Zeller as host, at four different temperature levels (10, 20, 30 and 40±1

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Experiments were conducted in a commercial tomato, Solanum lycopersicum L. (Solanaceae) greenhouse to compare the relative foraging effort and efficiency of two bumble bee species: Bombus impatiens Cresson, a species from northeastern North America, commercially reared and used for pollination in Mexico; and B. ephippiatus Say, a native species of Mexico and central America. B. ephippiatus was as efficient in pollination of tomatoes as B. impatiens, as indicated by all variables of fruit quality: fruit weight, number of seed per fruit, and maximum fruit diameter. The two species had similar levels of hourly and daily foraging activity. They had the same response to temperature fluctuation. Pollination rates by both species were similar and close to 100% throughout the sample period. However, B. impatiens showed greater foraging activity during the first half of the 27-d sample period, whereas B. ephipiatus had greater relative activity during the last half. This study establish that B. ephippiatus is as efficient as B. impatiens as a pollinator of tomatoes in greenhouses and thus a candidate as a managed pollinator. However, standard reliable methods for mass rearing of B. ephippiatus are not yet available. Such methods are necessary to ensure healthy colonies and optimum pollination for producers and will reduce the pressure for the unregulated collection of queens in the field and the subsequent reduction of populations of this species.

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Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) and Bactericera cockerelli Sulcer (Hemiptera: Psyllidae) are important pests in tomato, and the mirid Dicyphus hesperus Knight (Heteroptera: Miridae) has been shown as an effective predator of both pests. Although the predator was able to suppress populations of both pests, the remaining levels could still exceed tolerable levels. Thus, we here hypothesized whether the combination of D. hesperus with the specialist parasitoids Eretmocerus eremicus Rose y Zolnerowich (Hymenoptera: Aphelinidae) (whitefly) and Tamarixia triozae (Burks) (Hymenoptera: Eulophidae) (psyllid) would result in better pest control on a greenhouse scale. For that, we conducted a trial in which we compared the results against B. tabaci and B. cockerelli in greenhouses treated with D. hesperus alone or the predator in combination with the specialist parasitoids. The results showed that the predator was able to establish and suppress B. tabaci and B. cockerelli in tomato, but the addition of the specialist parasitoids resulted in better and more cost-effective pest control. Implementation of this method would therefore increase the robustness and reliability of biocontrol-based integrated pest management programmes for tomato crops, over methods based exclusively on D. hesperus release.