Studies on the Arthropod Fauna of Alfalfa: Ii. Arthropod–fungus Associations

Abstract

Observations were made during 1967 to 1969 at Ithaca, N.Y., supplemented by collections at New Cumberland and Carlisle, Pa., on arthropods associated with fungi occurring on alfalfa, Medicago saliva L. Five species of Coleoptera, two species of Diptera, one species each of Collembola and Psocoptera, and nine species of Acari were reared or collected consistently from fungus-covered alfalfa leaves, stems, and seed pods. Attraction to fungi on the plants, principally Alternaria sp., accounted for the presence on alfalfa of arthropod species that normally might be considered as accidentals or visitors. The mycetophagous species thus contributed to the richness of the alfalfa fauna. Immature stages of several species were collected only in late fall or on 3- or 4-year-old plants. The possible role of the fungus-feeding species in seasonal changes in the alfalfa fauna and changes in the fauna in successive years is discussed.

Avoidance of ladybird trails by an aphid parasitoid Aphidius ervi: active period and effects of prior oviposition experience

“…Aphids are attacked by a large guild of natural enemies (Hagen & van den Bosch, 1968;Wheeler, 1977;Dixon, 1998). Intraguild interactions are widespread in aphid natural enemy communities (Brodeur & Rosenheim, 2000).…”

Spider management in agroecosystems: Habitat manipulation

“…Soybean spider fauna were examined by LeSar and Unzicker (1978), and alfalfa spider fauna have been studied by Howell and Pienkowski (1971), Wheeler (1973), and Yeargan and Dondale (1974). Baily and Chada (1968) studied spider populations in grain sorghums.…”

Field evaluation of synthetic aphid sex pheromone in enhancing suppression of aphid abundance by their natural enemies

“…Intraguild predation (IGP), trophic interactions between organisms sharing the same resource, potentially changes the extent to which topdown forces by predator and parasitoid guilds affect herbivore populations. Aphids are associated with a large assemblage of insect natural enemies (Wheeler 1977;Nakashima and Akashi 2005). Fur-thermore, aphid parasitoids are usually the intraguild prey because parasitized hosts are potentially con-sumed by predators (Wheeler et al 1968;Hoelmer et al 1994;Wells et al 2001).…”

“…The pea aphid, Acyrthosiphon pisum (Harris) (Homoptera: Aphididae), is an important pest of alfalfa, Medicago sativa L., and other leguminous crops in many parts of the world (Cuperus et al 1982). Aphids are attacked by a large assemblage of insect natural enemies such as aphidiine parasitoids, and coccinellid, syrphid, nabid, anthocorid, chrysopid and carabid predators (Takada 1968;Wheeler 1977;Ekbom 1994;Nakashima and Akashi 2005). Among these natural enemies, the seven-spot ladybird beetle Coccinella septempunctata L. (Ekbom 1994) and the parasitoids Aphidius ervi Haliday and Praon barbatum Mackauer are reported as particularly important natural enemies of A. pisum on alfalfa (Senoo et al 2002;Nakashima and Akashi 2005).…”