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- Hidrogenionic potential (pH) of the attractant, trap density and control threshold for Ceratitis capitata (Diptera: tephritidae) on Hamlin oranges in São Paulo central region, BrazilPublication . Paiva, Paulo; Parra, JoséThis study evaluated the effect of initial pH values of 4.5, 6.5 and 8.5 of the attractant (protein bait) Milhocina® and borax (sodium borate) in the feld, on the capture of fruit flies in McPhail traps, using 1, 2, 4 and 8 traps per hectare, in order to estimate control thresholds in a Hamlin orange grove in the central region of the state of São Paulo. The most abundant fruit fly species was Ceratitis capitata, comprising almost 99% of the fruit flies captured, of which 80% were females. The largest captures of C. capitata were found in traps baited with Milhocina® and borax at pH 8.5. Captures per trap for the four densities were similar, indicating that the population can be estimated with one trap per hectare in areas with high populations. It was found positive relationships between captures of C. capitata and the number of Hamlin oranges damaged, 2 and 3 weeks after capture. It was obtained equations that correlate captures and damage levels which can be used to estimate control thresholds. The average loss caused in Hamlin orange fruits by C. capitata was 2.5 tons per hectare or 7.5% of production.
- Natural parasitism of Diaphorina citri Kuwayama (Hemiptera, Psyllidae) nymphs by Tamarixia radiata Waterston (Hymenoptera, Eulophidae) in São Paulo orange grovesPublication . Paiva, Paulo; Parra, JoséNatural parasitism of Diaphorina citri Kuwayama (Hemiptera, Psyllidae) nymphs by Tamarixia radiata Waterston (Hymenoptera, Eulophidae) in São Paulo orange groves. The psyllid Diaphorina citri Kuwayama 1908 has become the main citrus pest species in the state of São Paulo, Brazil, after the introduction of the huanglongbing or citrus greening. This study evaluated the parasitism of 3rd, 4th and 5th instar D. citri nymphs by Tamarixia radiata (Waterston, 1922) in citrus groves under a regimen of regular insecticide applications in ten producing regions: Araraquara, Barretos, Bauru, Botucatu, Franca, Itapetininga, Jaú, Limeira, Lins and São João da Boa Vista. Sixty-nine samples of new branches infested with nymphs of D. citri were collected from 2005 to 2008 in orange groves ranging from 1 to 20 years old, of the varieties Hamlin, Pera, Valencia and Natal. The parasitoid T. radiata is widely distributed in São Paulo orange groves, and was identified in 50 (72%) of the samples, showing a mean parasitism rate of 12.4%. The highest parasitism rate was observed in the “summer” (from January through March), with a mean of 25.7%. Nymphal parasitism was above 90% in two samples. The probable causes of the variations in parasitism of D. citri by T. radiata are discussed
- Life table analysis of Diaphorina citri (Hemiptera: Psyllidae) infesting sweet orange (Citrus sinensis) in São PauloPublication . Paiva, Paulo; Parra, JoséAn ecological life table for eggs and nymphs of Diaphorina citri Kuwayama (Hemiptera: Psyllidae) was constructed with data obtained from orange orchards (Citrus sinensis Osbeck) in 2 regions of the State of São Paulo, over 4 generations in the period from XI-2006 to V-2007, comprising spring, summer, and fall seasons. Young growing shoots with D. citri eggs present were identifed, and live individuals were counted until adult emergence. No predatory arthropods were observed in association with D. citri eggs and nymphs during the study. The mean parasitism of fourth- and ffth-instar nymphs by Tamarixia radiata Waterston (Hymenoptera: Eulophidae) was 2.3%. The durations of the egg–adult period were similar among the 4 generations, ranging from 18.0 to 24.7 d (at mean temperatures ranging from 21.6 to 26.0 °C) and followed the temperature requirement models obtained in the laboratory for D. citri. However, survival from the egg to the adult stage for the same period varied considerably from 1.7 to 21.4%; the highest mortalities were observed in the egg and small nymphal (frst- to thirdinstar) stages, which were considered to be key phases for population growth of the pest.
- Bioecologia do vetor Diaphorina citri e transmissão de bactérias associadas ao huanglongbingPublication . Parra, José; Lopes, João; Torres, Mariuxi; Nava, Dori; Paiva, PauloCom a descoberta do huanglongbing (HLB, ex-greening) no Brasil, em 2004, o psilídeoasiático-dos-citros, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), assumiu o status de praga-chave na citricultura pela sua capacidade de transmitir bactérias do gênero Candidatus Liberibacter spp., associadas a esta enfermidade. Por ser uma espécie exótica e de importância recente, há poucas informações sobre a biologia e ecologia desse psilídeo nas condições do Brasil, as quais são necessárias para o seu manejo. Portanto, este artigo busca compilar dados disponíveis sobre danos, dinâmica populacional e biologia de D. citri, com ênfase na influência de plantas hospedeiras, temperatura e umidade relativa do ar no seu desenvolvimento (duração e viabilidade dos estágios de ovo e ninfal), razão sexual e fecundidade. São descritos métodos alternativos de controle D. citri, com destaque para o controle biológico e a utilização do ectoparasitoide Tamarixia radiata (Waterston). Com base nas exigências térmicas deste parasitoide e de D. citri, elaborou-se o zoneamento ecológico para prever o número de gerações anuais de ambas as espécies no estado de São Paulo. Finalmente, são discutidos os mecanismos de transmissão de Ca. Liberibacter spp. por D. citri, baseando-se nas informações disponíveis sobre a interação patógeno-vetor.