Flutuação populacional de cigarrinhas-das-pastagens na Região Oeste do Paraná

Abstract

ResumoAs cigarrinha-das-pastagens são consideradas as mais importantes pragas em pastagens tropicais. Os danos ocasionados por estes insetos diminuem a produção das pastagens. O objetivo deste trabalho foi estudar a flutuação populacional de Notozulia entreriana, no período de junho de 2007 a junho de 2008, e a correlação com os fatores meteorológicos/ambientais (precipitação pluviométrica, temperatura, radiação solar diária e altura da pastagem). Para tanto, amostraram-se três áreas de pastagem no município de Marechal Cândido Rondon-PR. Foram realizadas amostragens de adultos e ninfas. Também se determinaram quais as espécies de cigarrinhas-das-pastagens (Hemiptera: Cercopidae) ocorrem na região oeste do Estado do Paraná. A flutuação populacional de N. entreriana apresentou quatro picos durante o período favorável de desenvolvimento -primavera/verão. A radiação solar diária apresentou maior correlação com a dinâmica populacional. Por outro lado, precipitação pluviométrica, temperatura e altura da pastagem apresentaram pouca correlação com a dinâmica populacional. A espécie que ocorreu com maior abundância foi N. entreriana, representando 88,4% do total de insetos coletados na região oeste do Paraná. Palavras-chave: Cercopídeos, radiação solar diária, dinâmica populacional, Cynodon dactylon. Rhynchospora sp AbstractThe spittlebugs are considered the most important pests in tropical pastures. The damages caused by these insects decrease the production of pastures. The objective this work was to study the population dynamics of Notozulia entreriana, from June 2007 to June 2008, and the correlation with meteorological and environmental factors (rainfall, temperature, daily solar radiation and pasture height). Therefore, sampled were made in three areas of grassland in the municipality of Marechal Cândido Rondon-PR. Sampling of adults and nymphs was made. Also we determined which species of spittlebugs (Hemiptera: Cercopidae) occur in the western region of Paraná State. The population fluctuation of N. entreriana showed four peaks during the period of favorable development -spring / summer. The daily solar radiation had a higher correlation with the population. Rainfall, temperature and pasture height had little correlation with the population dynamics. The species that occurred with greater abundance was N. entreriana, representing 88.4% of the total insects collected in western of Paraná State.

Incidence and Population Fluctuation of Spittlebugs on Three Perennial Grasses: On-Farm Assessments

“…The most abundant species collected in the plots was Notozulia entreriana (Berg, 1879) representing 73.7% of the total individuals collected (n = 1,536) during the sampling period, without, however, occur significant difference in the species proportion between the studied plots. Corroborating our findings, Lohmann et al (2010) also verified the predominance of N. entreriana in pastures of bermudagrass (C. dactylon) and sedges (Rhynchospora sp.) in the western region of Paraná State, Brazil.…”

“…Three or four population peaks were verified during the critical period of incidence of spittlebugs in previous studies conducted in South Brazil (Lohmann et al, 2010;Chiaradia et al, 2013). In the present work, three characteristic population peaks of spittlebugs were observed (Figure 2): the first in the end of September, the second in the middle of December, and the third starting in early February.…”

“…SCS 315 Catarina Gigante, which can indicate a plant resistance of antibiosis type. In previous studies conducted in South Brazil (Lohmann et al, 2010;Chiaradia et al, 2013), three or four population peaks were verified during the critical period of spittlebugs' incidence.…”

“…In the last years, significant population outbreaks of spittlebugs (Hemiptera: Cercopidae) have been observed in perennial grasses (Poaceae) established in farms in South of Brazil (Lohmann et al, 2010;Chiaradia et al, 2013). This situation is worrying local producers in relation to the continuous supply of forage along the year due to the significant damage caused by this pest species complex.…”

Relative contribution of rainfall and coconut hybrids to the abundance and composition of the Auchenorrhyncha community as potential vectors of phytoplasmas in the state of Sergipe, Brazil

“…The Auchenorrhyncha life cycle depends on a complex of factors, such as local humidity, temperature and photoperiod (Lohmann et al ., ; Koji et al ., ). The largest numbers of Auchenorrhyncha in the present study were captured in March and April in the dry‐to‐rainy season transition, corresponding to the period with the highest occurrence of O. sergipensis on coconut hybrids.…”