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- Natural parasitism of the Citrus Leafminer (Lepidoptera: Gracillariidae) over eight years in seven citrus regions of São Paulo, BrazilPublication . Paiva, Paulo; Yamamoto, Pedro TakaoThe citrus leafminer (CLM) Phyllocnists citrella Stainton (Lepidoptera: Gracillariidae) was frst recorded in Brazil in 1996. In 1998, the parasitoid Ageniaspis citricola Logvinovskaya (Hymenoptera: Encyrtdae) was introduced and established in many regions of the country. In this study, 130 onehour-samplings of sweet orange leaves (Citrus sinensis [L.] Osbeck) hostng CLM pupal chambers were carried out to estmate the CLM parasitsm rate (%) by its parasitoids in 7 regions of São Paulo State between 2000 and 2008. The sample sizes varied from 10 to 275 leaves (mean = 65). The most abundant parasitoid was the encyrtd A. citricola (found in 91.8% of the samplings). The highest level of CLM parasitsm by A. citricola was recorded in the southern region (Botucatu), 70.2 ± 6.6 (mean ± SEM), and the lowest level was recorded in the northern region (Barretos), 12.8 ± 5.7%. CLM parasitsm by A. citricola and by natve parasitoids (Galeopsomyia fausta LaSalle, Cirrospilus spp. and Elasmus sp.) did not differ between seasons. The 6-fold increase in the use of insectcides in citrus groves, afer 2004 when the Huanglongbing (HLB) disease was found in São Paulo State, did not reduce the level of CLM parasitsm. The level of parasitsm was 50.8 ± 4.2% before the advent of HLB (2000–2004) and 56.0 ± 4.4% thereafer (2005–2008), indicatng adaptaton of A. citricola in a disturbed agroecosystem.
- 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
- 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.