Author(s): Souza, B. & Carvalho, C. F.
Title: Population dynamics and seasonal occurrence of adults of Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) in a Citrus orchard in southern Brazil
Year: 2002
Volume: 48
Pages: 301-310.
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Abstract: Studies of the population dynamics of Chrysoperla externa (Hagen, 1861) adults were carried out in in Lavras, Minas Gerais, Brazil, in a citrus orchard, with the influence of precipitation, relative humidity and maximum, minimum and average temperatures on its population density being evaluated. Sampling was made weekly with an entomological net on 20 citrus trees in an area of ca. 2 ha, between 13:00 and 17:00 h, from May 1992 to April 1996. Annual sampling records for adults collected were 853, 629, 575 and 313, respectively, with a decreasing population trend during the period, mainly in the fourth year of study. An increase in the number of adults collected was observed from May to September, with peaks of 687 (80.5%), 344 (54.7%), 328 (57.0%) and 107 (34.2%) in September of 1992, 1993, 1994 and 1995, respectively. A remarkable decrease in the number of insects collected was observed in the months after September, with no insects or only few ones collected from November to March, December to February being the most critical period. There was an increase in the number of adults with the decrease in precipitation, relative humidity and temperature, with minimum and average temperature influencing the most.
Keywords: Neuroptera, Chrysopidae, Chrysoperla, citrus, weather factors, seasonal occurrence
Journal: Acta Zoologica Academiae Scientiarum Hungaricae
Journal abbreviation:
ISSN: 1217-8837
Publisher: Hungarian Natural History Museum, Budapest
Editor(s): Matskási, I., Peregovits, L. & Sziráki, Gy.