caa a22 4500 397571410 CHVBK 20180308164842.0 cr unu---uuuuu 161202e19961001xx s 000 0 eng 10.1093/ee/25.5.1045 doi (NATIONALLICENCE)oxford-10.1093/ee/25.5.1045 Sexual Maturation and Ovarian Activity in Rhammatocerus schistocercoides (Orthoptera: Acrididae), a Pest Grasshopper in the State of Mato Grosso in Brazil [Elektronische Daten] [My-Hanh Launois-Luong, Michel Lecoq] Sexual maturation and ovarian activity were studied in Rhammatocerus schistocercoides (Rehn, 1906) under natural conditions in the state of Mato Grosso in Brazil, a recognized outbreak area of this species. The end of the dry season marks the onset of sexual maturation, which could be associated with the photoperiod but not with the arrival of the 1st rains. This means that sexual maturation, although triggered at a set date, progresses under highly varied ecological conditions. This must have an important impact on ovarian activity and thus on the quantity of the eggs laid. Interannual fire and precipitation variations could modify population levels (through effects on ovarian activity, and also on the embryonic development success rate) and explain the outbreak cycles. Vitellogenesis failures were noted by frequently marked oocyte resorptions; an indication that the environmental conditions are not always optimal for egg maturation. Conditions during this study, at the beginning of the 1994- 1995 rainy season, were not entirely favorable because ovarian yield was only 59%. Pseudo-corpora lutea were noted at the base of the ovarian pedicels, which has to our knowledge never been reported. They slightly complicated the current study and have been a source of confusion in the past. © 1996 Entomological Society of America Population Ecology nationallicence Rhammatocerus schistocercoides nationallicence grasshopper nationallicence sexual maturation nationallicence ovarian activity nationallicence Brazil nationallicence Launois-Luong My-Hanh CIRAD, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, B.P. 5035 34032 Montpellier Cedex 1, France aut Lecoq Michel CIRAD, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, B.P. 5035 34032 Montpellier Cedex 1, France aut Environmental Entomology Oxford University Press 25/5(1996-10-01), 1045-1051 0046-225X 25:5<1045 1996 25 ee https://doi.org/10.1093/ee/25.5.1045 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/ee/25.5.1045 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Launois-Luong My-Hanh CIRAD, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, B.P. 5035 34032 Montpellier Cedex 1, France aut NATIONALLICENCE 700 1- Lecoq Michel CIRAD, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, B.P. 5035 34032 Montpellier Cedex 1, France aut NATIONALLICENCE 773 0- Environmental Entomology Oxford University Press 25/5(1996-10-01), 1045-1051 0046-225X 25:5<1045 1996 25 ee Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford