Attraction of Cnaphalocrocis medinalis (Lepidoptera: Crambidae) males in Southeast Asia to female sex pheromone traps: Field tests in southernmost China, northern Vietnam and southern Philippines with three synthetic pheromone blends regarding geographic variations

Abstract

Field tests of three types of synthetic sex pheromone blend (Japanese blend: Z11-18:Ald (55 mg), Z13-18:Ald (500 mg), Z11-18:OH (120 mg) and Z13-18:OH (180 mg), Indian blend: Z11-16:Ac (50 mg) and Z13-18:Ac (500 mg) and Philippine blend: Z11-16:Ac (500 mg) and Z13-18:Ac (10 mg) based on geographic variations in sex pheromones so far reported) for the rice leaffolder moth, Cnaphalocrocis medinalis Guenée (Lepidoptera: Crambidae), were performed at Nanning, in southernmost China, Hanoi, in northern Vietnam, and on Bohol, an island in the southern Philippines. In all of these tests, only the Japanese blend attracted significant numbers of male C. medinalis, while neither the Indian nor the Philippine blend showed any attractiveness to the males. The results at Nanning and Hanoi, from which the Japanese population may originate from, support the current inference about the migration routes of C. medinalis. On the contrary, the results on Bohol, in the Philippines, were unexpected and showed the presence of a population responding to the Japanese blend, but not to the Philippine blend.

Patterns of Genetic and Reproductive Traits Differentiation in Mainland vs. Corsican Populations of Bumblebees

“…in moths [160] or in bumblebees [161]); the consequence can range from simple regional variation (like dialects in songbirds [162] or in moths [163] or in solitary bees [141] consisting of different relative amounts of the same key compounds) to the establishment of a reproductive (pre-zygotic) isolation barriers between populations [164].…”

Subspecific differentiation in male reproductive traits and virgin queen preferences, in Bombus terrestris

“…According to the allopatric distribution of studied B. terrestris subspecies, the observed CLGS differentiations were most likely driven by a persistent lack of gene flow between them (see Estoup et al 1996;Lecocq et al 2013b), possibly reinforced by the preference of local females for sympatric males as previously suggested in insular bumblebees (see Lecocq et al 2013b). Such a differentiation of reproductive traits may directly interfere with the pre-mating communication between differentiated populations as observed in many organisms (Andersson 1994;Kawazu et al 2005). However, the differentiation consequences are poorly predictable without bioassays since they can lead to simple regional variation without reproductive isolation (i.e.…”

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