Fire effects on insects associated with the gamagrass Tripsacum dactyloides in Mexico

[No abstract available

Relationship between elements of the usability and emotions reported after use: A Mexican case

In central Mexico, the ant Brachymyrmex obscurior Forel feeds on nectar produced by extrafloral nectaries of Acacia pennatula (Schlecht. & Cham.) Benth However, no studies have determined whether the ant's visitation is related to plant nectar availability and whether ants protect A. pennatula from herbivory. The objectives of this 2-yr study (2000-2001) were to assess whether seasonal changes in ant visitation coincide with extrafloral nectar productivity in A. pennatula and to determine whether ants protect the plant. At the end of the dry season (April-June) B. obscurior was the only ant species on A. pennatula and extrafloral nectar production is limited to this period. Exclusion experiments, performed at the end of the dry season showed that A. pennatula did not receive a protective benefit when visited by ants. Branches with ants and branches where ants are excluded had similar numbers of the nonmyrmecophile leafhopper Sibovia sp. which was the only herbivore observed under natural conditions. " Birkhauser Verlag, 2005.",,,,,,"10.1007/s00040-004-0777-6",,,"http://hdl.handle.net/20.500.12104/44173","http://www.scopus.com/inward/record.url?eid=2-s2.0-20844448609&partnerID=40&md5=cfd06bb9c21beb0e1a00479fb014327e",,,,,,"2",,"Insectes Sociaux",,"10

Chitosan improves insulin sensitivity as determined by the euglycemic-hyperinsulinemic clamp technique in obese subjects

Native parasitoids of the adult Mexican corn leafhopper, Dalbulus elimatus (Ball), and corn leafhopper, Dalbulus maidis (Delong and Wolcott), are described and their rates of parasitism on maize, Zea mays L., common barley, Hordeum vulgare L., and sorghum, Sorghum bicolor (L.) Moench (Poaceae) in central Mexico are determined. The survey was conducted throughout an annual cycle, with sampling of the previous season's crops when they were available. Leafhoppers showing evidence of parasitism were reared individually in the laboratory to obtain adult parasitoids. Adult D. elimatus were parasitized on winter maize, barley, and sorghum by the fly Eudorylas subopacus (Loew) (Diptera: Pipunculidae) and the wasp Gonatopus bartletti Olmi (Hymenoptera: Dryinidae), whereas adult D. maidis were parasitized by these fly and wasp parasitoids on winter maize only. The highest rates of parasitism of D. elimatus by E. subopacus were 57.4% on maize, 39.6% on barley, and 48.8% on sorghum. The highest rate of parasitism of D. maidis by E. subopacus was 20.4% on maize. In contrast, the highest rates of parasitism of D. elimatus by G. bartletti were 9.4% on maize, 2.7% on barley, and 25.8% on sorghum. The highest rate of parasitism of D. maidis by G. bartletti was 7.1% on maize. These results indicate that winter crops are habitats of E. subopacus and G. bartletti during the winter season. This is the first report of D. elimatus and D. maidis being parasitized by E. subopacus and of D. elimatus being parasitized by G. bartletti. " 2007 Entomological Society of Canada.",,,,,,,,,"http://hdl.handle.net/20.500.12104/43033","http://www.scopus.com/inward/record.url?eid=2-s2.0-34948888826&partnerID=40&md5=04465b711c5f112dfeffbbe8f09d835

Diversity of leafhoppers and their hymenopterous parasitoids in maize, teosinte and gamagrass related ecosystems

[No abstract available

Native parasitoids of Dalbulus elimatus and Dalbulus maidis (Hemiptera: Cicadellidae) in winter crops of central Mexico

Native parasitoids of the adult Mexican corn leafhopper, Dalbulus elimatus (Ball), and corn leafhopper, Dalbulus maidis (Delong and Wolcott), are described and their rates of parasitism on maize, Zea mays L., common barley, Hordeum vulgare L., and sorghum, Sorghum bicolor (L.) Moench (Poaceae) in central Mexico are determined. The survey was conducted throughout an annual cycle, with sampling of the previous season's crops when they were available. Leafhoppers showing evidence of parasitism were reared individually in the laboratory to obtain adult parasitoids. Adult D. elimatus were parasitized on winter maize, barley, and sorghum by the fly Eudorylas subopacus (Loew) (Diptera: Pipunculidae) and the wasp Gonatopus bartletti Olmi (Hymenoptera: Dryinidae), whereas adult D. maidis were parasitized by these fly and wasp parasitoids on winter maize only. The highest rates of parasitism of D. elimatus by E. subopacus were 57.4% on maize, 39.6% on barley, and 48.8% on sorghum. The highest rate of parasitism of D. maidis by E. subopacus was 20.4% on maize. In contrast, the highest rates of parasitism of D. elimatus by G. bartletti were 9.4% on maize, 2.7% on barley, and 25.8% on sorghum. The highest rate of parasitism of D. maidis by G. bartletti was 7.1% on maize. These results indicate that winter crops are habitats of E. subopacus and G. bartletti during the winter season. This is the first report of D. elimatus and D. maidis being parasitized by E. subopacus and of D. elimatus being parasitized by G. bartletti. © 2007 Entomological Society of Canada

Fire effects on insects associated with the gamagrass Tripsacum dactyloides in Mexico

[No abstract available

Halictophagus naulti sp. n. (Strepsiptera: Halictophagidae), a New Species Parasitic in the Corn Leafhopper (Homoptera: Cicadellidae) from Mexico

A new species of Strepsitera Halictophagus naulti (Halictophagidae) that is parasitic in the corn leafhopper Dalbulus maidis (Delong and Wolcott) from the Mexican state of Morelos is described

Ants (Hymenoptera: Formicidae) and trophobiont leafhopper nymphs (Hemiptera: Cicadellidae) become more abundant in shaded conditions: Implications for mutualism

Abiotic factors have dramatic effects on herbivore insect populations. However, little is known about the effects of the abiotic factor of shade on the mutualism between ants and Hemiptera (aphids, scales, mealy bugs, whiteflies, treehoppers, leafhoppers). The trophobiont leafhopper Dalbulus quinquenotatus DeLong & Nault (Hemiptera: Cicadellidae) is obligatorily tended by the ant Brachymyrmex obscurior Forel (Hymenoptera: Formicidae) on the basal leaves of gamagrass Tripsacum dactyloides L. (Poales: Poaceae). To better understand the effect of abiotic factors on this relationship, we conducted a comparative experiment to investigate the abundance of ants and leafhoppers (nymphs and adults) under shaded and full-sunlight conditions. We observed mutualism between D. quinquenotatus and B. obscurior on both shaded and non-shaded gamagrasses. Nevertheless, the greatest number of B. obscurior were found tending the greatest number of D. quinquenotatus on shaded T. dactyloides. Most of these leafhoppers were nymphs. Nymphs were observed in clusters on the basal leaves. On the other hand, ant-tended D. quinquenotatus adults were observed at similar frequencies on shaded and non-shaded gamagrasses. The adults were also seen on the basal leaves and produced honeydew, but were more mobile than the nymphs. Our results highlight the importance of abiotic factors in mutualism as well as the complex interaction between shaded plants, immature leafhoppers, and tending ants. Zapotitlán Florida Entomologist 2014