Comparative analysis of Monilinia fructicola and M. laxa isolates from Brazil: monocyclic components of peach brown rot / Análise comparativa de isolados de Monilinia fructicola e M. laxa do Brasil: componentes monocíclicos da podridão parda

Brown rot is the most important disease of peaches in Brazil. The objective of this study was to compare the brown rot monocyclic components from Monilinia fructicola and M. laxa isolates from Brazil on peaches, due to the detection of M. laxa in the São Paulo production area. Conidia germination and pathogen sporulation were assessed in vitro under a temperature range of 5-35oC and wetness duration of 6-48h. Incubation and latent periods, disease incidence, disease severity and pathogen reproduction on peach fruit were evaluated under 10, 15, 20, 25 and 30oC and wetness duration of 6, 12 and 24h. Six of seven parameters of a generalised beta function fitted to conidia germination of M. fructicola and M. laxa were similar. Only the shape parameter was higher for M. fructicola indicating that the range of temperatures and wetness periods favourable for germination is wider for M. laxa than for M. fructicola. The optimum temperature for brown rot development caused by M. fructicola was 24.5oC and for. Monilinia laxa was 19.8oC. At 10oC M. laxa lesions produced more conidia than M. fructicola, and the opposite occurred at 30oC. The estimated maximum temperature for lesion development was also higher for M. fructicola than for M. laxa. M. fructicola is favored by warmer weather than M. laxa and the presence and impact of this specie in Brazil must be investigated especially in the South states.(AU)

Podridão parda é a doença mais importante de pêssegos no Brasil. O objetivo deste estudo foi comparar os componentes monocíclicos da podridão parda de isolados brasileiros de M. fructicola e M. laxa, devido à detecção de M. laxa em uma área de produção de São Paulo. A germinação de conídios e esporulação do patógeno foram avaliadas in vitro sob uma faixa de temperatura de 5-35oC e duração do molhamento de 6-48h. Os períodos de incubação e de latência, a incidência da doença, a severidade da doença e a reprodução do patógeno em frutos de pêssego foram avaliados em 10, 15, 20, 25 e 30ºC e duração de molhamento de 6, 12 e 24h. Seis dos sete parâmetros de uma função beta generalizada para germinação de conídios de M. fructicola e M. laxa foram semelhantes. Apenas o parâmetro de forma foi mais alto para M. fructicola indicando que a gama de temperaturas e períodos de molhamento favoráveis para germinação é maior para M. laxa do que para M. fructicola. A temperatura ideal para o desenvolvimento de podridão parda causada por M. fructicola foi 24,5oC e para Monilinia laxa foi 19,8oC. A 10oC lesões de M. laxa produziram mais conídios que as de M. fructicola, e o inverso ocorreu a 30oC. A temperatura máxima estimada para o desenvolvimento de lesões também foi maior para M. fructicola do que para M. laxa. M. fructicola é favorecido por um clima mais quente do que M. laxa e a presença e impacto deste patógeno no Brazil deve ser acompanhado em especial no estados do sul do país.(AU)

Comparative analysis of Monilinia fructicola and M. laxa isolates from Brazil: monocyclic components of peach brown rot / Análise comparativa de isolados de Monilinia fructicola e M. laxa do Brasil: componentes monocíclicos da podridão parda

Brown rot is the most important disease of peaches in Brazil. The objective of this study was to compare the brown rot monocyclic components from Monilinia fructicola and M. laxa isolates from Brazil on peaches, due to the detection of M. laxa in the São Paulo production area. Conidia germination and pathogen sporulation were assessed in vitro under a temperature range of 5-35oC and wetness duration of 6-48h. Incubation and latent periods, disease incidence, disease severity and pathogen reproduction on peach fruit were evaluated under 10, 15, 20, 25 and 30oC and wetness duration of 6, 12 and 24h. Six of seven parameters of a generalised beta function fitted to conidia germination of M. fructicola and M. laxa were similar. Only the shape parameter was higher for M. fructicola indicating that the range of temperatures and wetness periods favourable for germination is wider for M. laxa than for M. fructicola. The optimum temperature for brown rot development caused by M. fructicola was 24.5oC and for. Monilinia laxa was 19.8oC. At 10oC M. laxa lesions produced more conidia than M. fructicola, and the opposite occurred at 30oC. The estimated maximum temperature for lesion development was also higher for M. fructicola than for M. laxa. M. fructicola is favored by warmer weather than M. laxa and the presence and impact of this specie in Brazil must be investigated especially in the South states.

Podridão parda é a doença mais importante de pêssegos no Brasil. O objetivo deste estudo foi comparar os componentes monocíclicos da podridão parda de isolados brasileiros de M. fructicola e M. laxa, devido à detecção de M. laxa em uma área de produção de São Paulo. A germinação de conídios e esporulação do patógeno foram avaliadas in vitro sob uma faixa de temperatura de 5-35oC e duração do molhamento de 6-48h. Os períodos de incubação e de latência, a incidência da doença, a severidade da doença e a reprodução do patógeno em frutos de pêssego foram avaliados em 10, 15, 20, 25 e 30ºC e duração de molhamento de 6, 12 e 24h. Seis dos sete parâmetros de uma função beta generalizada para germinação de conídios de M. fructicola e M. laxa foram semelhantes. Apenas o parâmetro de forma foi mais alto para M. fructicola indicando que a gama de temperaturas e períodos de molhamento favoráveis para germinação é maior para M. laxa do que para M. fructicola. A temperatura ideal para o desenvolvimento de podridão parda causada por M. fructicola foi 24,5oC e para Monilinia laxa foi 19,8oC. A 10oC lesões de M. laxa produziram mais conídios que as de M. fructicola, e o inverso ocorreu a 30oC. A temperatura máxima estimada para o desenvolvimento de lesões também foi maior para M. fructicola do que para M. laxa. M. fructicola é favorecido por um clima mais quente do que M. laxa e a presença e impacto deste patógeno no Brazil deve ser acompanhado em especial no estados do sul do país.

Control of Grapholita molesta (Busck, 1916) (Lepidoptera: Tortricidae) with entomopathogenic nematodes (Rhabditida: Heterorhabditidae, Steinernematidae) in peach orchards.

Oriental fruit moth Grapholita molesta (Busck, 1916) (Lepidoptera: Tortricidae) is considered a major pest in temperate fruit trees, such as peach and apple. Entomopathogenic nematodes (EPNs) are regarded as viable for pest management control due to their efficiency against tortricid in these trees. The objective of this study was to evaluate the effectiveness of native EPNs from Rio Grande do Sul state against pre-pupae of G. molesta under laboratory and field conditions. In the laboratory, pre-pupae of G. molesta were placed in corrugated cardboard sheets inside glass tubes and exposed to 17 different EPNs strains at concentrations of 6, 12, 24, 48 and 60 IJs/cm(2) and maintained at 25 °C, 70 ± 10% RH and photophase of 16 h. Insect mortality was recorded 72 h after inoculation of EPNs. Steinernema rarum RS69 and Heterorhabditis bacteriophora RS33 were the most virulent strains and selected for field application (LC95 of 70.5 and 53.8 IJs/cm(2), respectively). Both strains were highly efficient under field conditions when applied in aqueous suspension directed to larvae on peach tree trunk, causing mortality of 94 and 97.0%, respectively.

Natural enemies associated to aphids in peach orchards in Araucária, Paraná, Brazil / Inimigos naturais associados a afídeos em pomares de pessegueiros em Araucária, Estado do Paraná, Brasil

Natural enemies of the Class Insecta are important agents in the balance of aphid populations and an alternative to using insecticides to control these insects. The aim of this study was to identify the species of natural enemies associated with aphids present in peach orchards and observe the efficiency of capturing different sampling methods. The experiment was conducted from July, 2005 to September, 2006 in six peach orchards 'Chimarrita', in Araucária, PR, Brazil. The samples were taken by visual analysis in peach plants and weeds, yellow pan traps, sticky traps and funnels. Predator species were identified: Cryptolaemus montrouzieri, Cycloneda pulchella, Cycloneda sanguinea, Eriopis connexa, Harmonia axyridis, Hippodamia convergens and Scymnus sp. (Coleoptera, Coccinellidae), Allograpta sp., Palpada sp. and Toxomerus sp. (Diptera, Syrphidae) and Chrysoperla sp. (Neuroptera, Chrysopidae) and the parasitoids: Diaretiella rapae, Opius sp. and Praon sp (Braconidae). Examples of Encyrtidae and Eulophidae await identification. Chrysoperla sp. was a less abundant species. There were no statistically significant differences between the different sampling methods tested.

Os inimigos naturais da Classe Insecta são importantes agentes no equilíbrio das populações de afídeos e uma forma alternativa ao uso de inseticidas no controle desses insetos. O objetivo deste estudo foi identificar as espécies de inimigos naturais associados aos afídeos presentes em pomares de pessegueiros, além de verificar a eficiência de captura de diferentes métodos de amostragem. O experimento foi realizado de julho de 2005 a setembro de 2006, em seis pomares de pessegueiros 'Chimarrita' em Araucária-PR, Brasil. As amostragens foram realizadas por meio de: análise visual em plantas de pessegueiros e plantas invasoras; armadilhas amarelas; armadilhas adesivas, e funil. Foram identificados os predadores: Cryptolaemus montrouzieri, Cycloneda pulchella, Cycloneda sanguinea, Eriopis connexa, Harmonia axyridis, Hippodamia convergens, Scymnus sp. (Coleoptera, Coccinellidae), Allograpta sp., Palpada sp., Toxomerus sp. (Diptera, Syrphidae) e Chrysoperla sp. (Neuroptera, Chrysopidae), além dos parasitoides: Diaretiella rapae, Opius sp. e Praon sp. (Braconidae). Exemplares de Encyrtidae e Eulophidae aguardam identificação. Chrysoperla sp. foi a espécie menos abundante. Não foram constatadas diferenças estatísticas significativas entre os diferentes métodos de amostragem testados.

Insecticide resistance mechanisms in the green peach aphid Myzus persicae (Hemiptera: Aphididae) I: A transcriptomic survey.

BACKGROUND: Insecticide resistance is one of the best examples of rapid micro-evolution found in nature. Since the development of the first synthetic insecticide in 1939, humans have invested considerable effort to stay ahead of resistance phenotypes that repeatedly develop in insects. Aphids are a group of insects that have become global pests in agriculture and frequently exhibit insecticide resistance. The green peach aphid, Myzus persicae, has developed resistance to at least seventy different synthetic compounds, and different insecticide resistance mechanisms have been reported worldwide. METHODOLOGY/PRINCIPAL FINDINGS: To further characterize this resistance, we analyzed genome-wide transcriptional responses in three genotypes of M. persicae, each exhibiting different resistance mechanisms, in response to an anti-cholinesterase insecticide. The sensitive genotype (exhibiting no resistance mechanism) responded to the insecticide by up-regulating 183 genes primarily ones related to energy metabolism, detoxifying enzymes, proteins of extracellular transport, peptidases and cuticular proteins. The second genotype (resistant through a kdr sodium channel mutation), up-regulated 17 genes coding for detoxifying enzymes, peptidase and cuticular proteins. Finally, a multiply resistant genotype (carrying kdr and a modified acetylcholinesterase), up-regulated only 7 genes, appears not to require induced insecticide detoxification, and instead down-regulated many genes. CONCLUSIONS/SIGNIFICANCE: This study suggests strongly that insecticide resistance in M. persicae is more complex that has been described, with the participation of a broad array of resistance mechanisms. The sensitive genotype exhibited the highest transcriptional plasticity, accounting for the wide range of potential adaptations to insecticides that this species can evolve. In contrast, the multiply resistant genotype exhibited a low transcriptional plasticity, even for the expression of genes encoding enzymes involved in insecticide detoxification. Our results emphasize the value of microarray studies to search for regulated genes in insects, but also highlights the many ways those different genotypes can assemble resistant phenotypes depending on the environmental pressure.

Insecticide resistance mechanisms in the green peach aphid Myzus persicae (Hemiptera: Aphididae) II: Costs and benefits.

BACKGROUND: Among herbivorous insects that have exploited agro-ecosystems, the peach-potato aphid, Myzus persicae, is recognized as one of the most important agricultural pests worldwide. Uses over 400 plant species and has evolved different insecticides resistance mechanisms. As M. persicae feeds upon a huge diversity of hosts, it has been exposed to a wide variety of plant allelochemicals, which probably have promoted a wide range of detoxification systems. METHODOLOGY/PRINCIPAL FINDINGS: In this work we (i) evaluated whether insecticide resistance mutations (IRM) in M. persicae can give an advantage in terms of reproductive fitness when aphids face two hosts, pepper (Capsicum annuum) a suitable host and radish (Raphanus sativus) the unfavorable host and (ii) examined the transcriptional expression of six genes that are known to be up-regulated in response to insecticides. Our results show a significant interaction between host and IRM on the intrinsic rate of increase (r(m)). Susceptible genotypes (not carrying insensitivity mutations) had a higher r(m) on pepper, and the transcriptional levels of five genes increased on radish. The r(m) relationship was reversed on the unfavorable host; genotypes with multiple IRM exhibited higher r(m), without altering the transcriptional levels of the studied genes. Genotypes with one IRM kept a similar r(m) on both hosts, but they increased the transcriptional levels of two genes. CONCLUSIONS/SIGNIFICANCE: Although we have studied only nine genotypes, overall our results are in agreement with the general idea that allelochemical detoxification systems could constitute a pre-adaptation for the development of insecticide resistance. Genotypes carrying IRM exhibited a higher r(m) than susceptible genotypes on radish, the more unfavorable host. Susceptible genotypes should be able to tolerate the defended host by up-regulating some metabolic genes that are also responding to insecticides. Hence, our results suggest that the trade-off among resistance mechanisms might be quite complex, with a multiplicity of costs and benefits depending on the environment.

Natural enemies associated to aphids in peach orchards in Araucária, Paraná, Brazil.

Natural enemies of the Class Insecta are important agents in the balance of aphid populations and an alternative to using insecticides to control these insects. The aim of this study was to identify the species of natural enemies associated with aphids present in peach orchards and observe the efficiency of capturing different sampling methods. The experiment was conducted from July, 2005 to September, 2006 in six peach orchards 'Chimarrita', in Araucária, PR, Brazil. The samples were taken by visual analysis in peach plants and weeds, yellow pan traps, sticky traps and funnels. Predator species were identified: Cryptolaemus montrouzieri, Cycloneda pulchella, Cycloneda sanguinea, Eriopis connexa, Harmonia axyridis, Hippodamia convergens and Scymnus sp. (Coleoptera, Coccinellidae), Allograpta sp., Palpada sp. and Toxomerus sp. (Diptera, Syrphidae) and Chrysoperla sp. (Neuroptera, Chrysopidae) and the parasitoids: Diaretiella rapae, Opius sp. and Praon sp (Braconidae). Examples of Encyrtidae and Eulophidae await identification. Chrysoperla sp. was a less abundant species. There were no statistically significant differences between the different sampling methods tested.

Population fluctuation and faunal indices of aphids (Hemiptera, Aphididae) in peach orchards in Araucária, PR.

Aphids are sap-sucking insects that mainly attack shoots and young leaves of peach trees and many other plant species; however, knowledge of the Brazilian aphid fauna is scant. The objective of this study was to identify aphid species collected in peach orchards (Prunus persica Batsch) and to determine their faunal indices for occurrence and dominance. The experiment was conducted from July 2005 to September 2006 in six Chimarrita peach orchards in the municipality of Araucária, PR, Brazil. The survey of aphid species was conducted by visual samplings on peach trees and using Möericke-type yellow traps containing water. A faunal analysis was made using aphid occurrence and dominance indices. Brachycaudus persicae (Passerini, 1860) was the only aphid species that was found colonizing peach in Araucária/PR. Although most aphids collected were classified as rare, some can be considered potential peach colonizers, such as Myzus persicae (Sulzer, 1776) which was given the status of common or intermediate in some of the orchards studied. The population fluctuation of aphids showed a negative correlation with rainfall and positive correlation with temperature and relative humidity.

Population fluctuation and faunal indices of aphids (Hemiptera, Aphididae) in peach orchards in Araucária, PR / Flutuação populacional e índices faunísticos de afídeos (Hemiptera, Aphididae) em pomares de pessegueiros em Araucária, PR

Aphids are sap-sucking insects that mainly attack shoots and young leaves of peach trees and many other plant species; however, knowledge of the Brazilian aphid fauna is scant. The objective of this study was to identify aphid species collected in peach orchards (Prunus persica Batsch) and to determine their faunal indices for occurrence and dominance. The experiment was conducted from July 2005 to September 2006 in six Chimarrita peach orchards in the municipality of Araucária, PR, Brazil. The survey of aphid species was conducted by visual samplings on peach trees and using Mõericke-type yellow traps containing water. A faunal analysis was made using aphid occurrence and dominance indices. Brachycaudus persicae (Passerini, 1860) was the only aphid species that was found colonizing peach in Araucária/PR. Although most aphids collected were classified as rare, some can be considered potential peach colonizers, such as Myzus persicae (Sulzer, 1776) which was given the status of common or intermediate in some of the orchards studied. The population fluctuation of aphids showed a negative correlation with rainfall and positive correlation with temperature and relative humidity.

Os afídeos são insetos sugadores de seiva que atacam principalmente brotações e folhas novas de pessegueiros e de diversas outras espécies vegetais, porém o conhecimento sobre a afidofauna brasileira é escasso. O objetivo deste trabalho foi identificar as espécies de afídeos coletadas em pomares de pessegueiros (Prunus persica Batsch) e analisar os índices faunísticos de ocorrência e dominância. O experimento foi realizado de julho de 2005 a setembro de 2006 em seis pomares de pessegueiros da cultivar Chimarrita no município de Araucária, PR. O levantamento das espécies de afídeos foi realizado por meio de amostragens visuais em pessegueiros e armadilhas amarelas de água do tipo Mõericke. Brachycaudus persicae (Passerini, 1860) foi a única espécie de afídeo encontrada colonizando pessegueiros em Araucária, PR. Apesar da maioria das espécies de afídeos coletadas serem classificadas como raras, algumas podem ser consideradas colonizadoras potenciais de pessegueiros como Myzus persicae (Sulzer, 1776) que recebeu o status de comum ou intermediária em alguns dos pomares estudados. A flutuação populacional de afídeos apresentou uma correlação negativa com a precipitação pluviométrica e positiva com a temperatura e a umidade relativa do ar.

Diversity and seasonality of fruit flies (Diptera: Tephritidae and Lonchaeidae) and their parasitoids (Hymenoptera: Braconidae and Figitidae) in orchards of guava, loquat and peach.

This work was carried out in orchards of guava progenies, and loquat and peach cultivars, in Monte Alegre do Sul, SP, Brazil, in 2002 and 2003. Guavas and loquats were bagged and unbagged bi-weekly and weekly, respectively, for assessment of the infestation period. Peach was only bagged weekly. The assays started when the fruits were at the beginning of development, but still green. Ripe fruits were taken to the laboratory and placed individually into plastic cups. McPhail plastic traps containing torula yeast were hung from January 2002 to January 2004 to assess the fruit fly population in each orchard, but only the Ceratitis capitata population is here discussed. Five tephritid species were reared from the fruits: Anastrepha bistrigata Bezzi, A. fraterculus (Wiedemann), A. obliqua (Macquart), A. sororcula Zucchi, and C. capitata, in addition to six lonchaeid species: Neosilba certa (Walker), N. glaberrima (Wiedemann), N. pendula (Bezzi), N. zadolicha McAlpine and Steyskal, Neosilba sp. 4, and Neosilba sp. 10 (both species are in the process of being described by P. C. Strikis), as well as some unidentified Neosilba species. Ten parasitoid species were obtained from fruit fly puparia, of which five were braconids: Asobara anastrephae (Muesebeck), Doryctobracon areolatus (Szépligeti), D. brasiliensis (Szépligeti), Opius bellus Gahan, and Utetes anastrephae (Viereck), and five figitids: Aganaspis pelleranoi (Brèthes), Dicerataspis grenadensis Ashmead, Lopheucoila anastrephae (Rhower), Leptopilina boulardi (Barbotin, Carlton and Kelner-Pillaut), and Trybliographa infuscata Diaz, Gallardo and Uchôa. Ceratitis capitata showed a seasonal behavior with population density peaking at the second semester of each year. Anastrepha and Neosilba species remained in the orchards throughout both years.

Diversity and seasonality of fruit flies (Diptera: Tephritidae and Lonchaeidae) and their parasitoids (Hymenoptera: Braconidae and Figitidae) in orchards of guava, loquat and peach / Diversidade e variação sazonal de moscas-das-frutas (Diptera: Tephritidae, Lonchaeidae) e seus parasitóides (Hymenoptera: Braconidae, Figitidae) em pomares de goiaba, nêspera e pêssego

This work was carried out in orchards of guava progenies, and loquat and peach cultivars, in Monte Alegre do Sul, SP, Brazil, in 2002 and 2003. Guavas and loquats were bagged and unbagged bi-weekly and weekly, respectively, for assessment of the infestation period. Peach was only bagged weekly. The assays started when the fruits were at the beginning of development, but still green. Ripe fruits were taken to the laboratory and placed individually into plastic cups. McPhail plastic traps containing torula yeast were hung from January 2002 to January 2004 to assess the fruit fly population in each orchard, but only the Ceratitis capitata population is here discussed. Five tephritid species were reared from the fruits: Anastrepha bistrigata Bezzi, A. fraterculus (Wiedemann), A. obliqua (Macquart), A. sororcula Zucchi, and C. capitata, in addition to six lonchaeid species: Neosilba certa (Walker), N. glaberrima (Wiedemann), N. pendula (Bezzi), N. zadolicha McAlpine and Steyskal, Neosilba sp. 4, and Neosilba sp. 10 (both species are in the process of being described by P. C. Strikis), as well as some unidentified Neosilba species. Ten parasitoid species were obtained from fruit fly puparia, of which five were braconids: Asobara anastrephae (Muesebeck), Doryctobracon areolatus (Szépligeti), D. brasiliensis (Szépligeti), Opius bellus Gahan, and Utetes anastrephae (Viereck), and five figitids: Aganaspis pelleranoi (Brèthes), Dicerataspis grenadensis Ashmead, Lopheucoila anastrephae (Rhower), Leptopilina boulardi (Barbotin, Carlton and Kelner-Pillaut), and Trybliographa infuscata Diaz, Gallardo and Uchôa. Ceratitis capitata showed a seasonal behavior with population density peaking at the second semester of each year. Anastrepha and Neosilba species remained in the orchards throughout both years.

Este trabalho foi realizado em três pomares em Monte Alegre do Sul, SP, em 2002 e 2003, representados por coleção de progênies de goiabeiras, de cultivares de nespereiras e de cultivares de pessegueiros. O período de infestação foi determinado por meio de ensacamento e desensacamento quinzenal e semanal de goiabas e nêsperas, respectivamente, e pelo ensacamento semanal de pêssegos. Os ensaios iniciaram-se com os frutos verdes (princípio de desenvolvimento). Os frutos maduros foram levados ao laboratório e acondicionados individualmente em copos plásticos. A flutuação populacional de Ceratitis capitata (Wiedemann) foi avaliada por meio de armadilhas plásticas modelo McPhail com torula em cada pomar, de janeiro/2002 a janeiro/2004. Dos frutos foram obtidas cinco espécies de tefritídeos: Anastrepha bistrigata Bezzi, A. fraterculus (Wiedemann), A. obliqua (Macquart), A. sororcula Zucchi e C. capitata e seis de lonqueídeos: Neosilba certa (Walker), N. glaberrima (Wiedemann), N. pendula (Bezzi), N. zadolicha McAlpine and Steyskal, Neosilba sp. 4 e Neosilba sp. 10, além de algumas espécies não-identificadas. Foram obtidas 10 espécies de parasitóides, cinco da família Braconidae - Asobara anastrephae (Muesebeck), Doryctobracon areolatus (Szépligeti), D. brasiliensis (Szépligeti), Opius bellus Gahan e Utetes anastrephae (Viereck) - e cinco da família Figitidae - Aganaspis pelleranoi (Brèthes), Dicerataspis grenadensis Ashmead, Lopheucoila anastrephae (Rhower), Leptopilina boulardi (Barbotin, Carlton and Kelner-Pillaut) e Trybliographa infuscata Diaz, Gallardo and Uchôa. Ceratitis capitata apresentou comportamento sazonal com picos populacionais durante o segundo semestre dos dois anos. As espécies de Anastrepha e de Neosilba permaneceram nos pomares durante os dois anos.

Thrips (Thysanoptera: Thripidae, Phlaeothripidae) damaging peach in Paranapanema, São Paulo State, Brazil.

Seeking to identify thrips species associated to peach and the injuries they cause, plants of Aurora and Tropic Beauty cultivars were weekly monitored, from May to August of 2005, in Holambra II district, in Paranapanema, SP. Flowers and fruits from six plants per hectare were sampled by the hitting technique. Frankliniella occidentalis (Pergande), F. schultzei (Trybom), F. gardenia (Moulton), F. condei John, F. insularis (Franklin) and Thrips tabaci Lindeman, in Thripidae, and Haplothrips gowdeyi (Franklin), in Phlaeothripidae were identified. F. occidentalis was dominant, comprising 55.7% of the total specimens sampled. Slight and severe injuries were registered in fruits.

Thrips (Thysanoptera: Thripidae, Phlaeothripidae) damaging peach in Paranapanema, São Paulo State, Brazil / Tripes (Thysanoptera: Thripidae, Phlaeothripidae) danificando pessegueiro Prunus persica (L.) Batsch (Rosaceae) em Paranapanema, SP

Seeking to identify thrips species associated to peach and the injuries they cause, plants of Aurora and Tropic Beauty cultivars were weekly monitored, from May to August of 2005, in Holambra II district, in Paranapanema, SP. Flowers and fruits from six plants per hectare were sampled by the hitting technique. Frankliniella occidentalis (Pergande), F. schultzei (Trybom), F. gardenia (Moulton), F. condei John, F. insularis (Franklin) and Thrips tabaci Lindeman, in Thripidae, and Haplothrips gowdeyi (Franklin), in Phlaeothripidae were identified. F. occidentalis was dominant, comprising 55.7 percent of the total specimens sampled. Slight and severe injuries were registered in fruits.

Objetivando identificar as espécies de tripes associadas ao pessegueiro e as injúrias causadas, pomares das cultivares Aurora e Tropic Beauty foram monitorados semanalmente, de maio a agosto de 2005, no Distrito de Holambra II, em Paranapanema, SP. Flores e frutos de cada seis plantas por hectare foram amostrados pela técnica da batida. Foram identificadas Frankliniella occidentalis (Pergande), F. schultzei (Trybom), F. gardenia (Moulton), F. condei John, F. insularis (Franklin) e Thrips tabaci Lindeman em Thripidae, e, Haplothrips gowdeyi (Franklin) em Phlaeothripidae. F. occidentalis foi dominante compondo 55,7 por cento do total de espécimes amostrado. Injúrias leves e severas foram registradas nos frutos.

Enhanced micropropagation response and biocontrol effect of Azospirillum brasilense Sp245 on Prunus cerasifera L. clone Mr.S 2/5 plants.

Inoculation with Azospirillum brasilense Sp245 exerts beneficial effects on micropropagated plants of Prunus cerasifera L. clone Mr.S 2/5, as seen in the results of a comparative analysis of inoculated and non-inoculated explants, during both the rooting and acclimatation phases. The presence of Azospirillum brasilense Sp245 increased root system, root hair biomass production and apical activity. Although the presence of the bacteria had a positive effect on rooting, the addition of indolebutyric acid (IBA) to Murashige and Skoog (MS) medium was seen as indispensable in order to promote the rooting of explants. Aside from the promotion of plant growth, A. brasilense Sp245 protects plants against pathogen attacks, such as Rhizoctonia spp., with a plant survival rate of nearly 100% vs. 0% as seen in the negative control. The biocontrol effect of A. brasilense Sp245 on the fungal rhizospheric community has been confirmed by denaturing gradient gel electrophoresis (DGGE) profiles of the rhizospheric microbial community. This study indicates that A. brasilense Sp245 could be employed as a tool in plant biotechnology.

The population level of Eotetranychus lewisi and the concentration of carbohydrates in peach trees.

Lewis spider mite Eotetranychus lewisi (McGregor) is the most important pest in peach orchards, Prunus persica (L.) (Batsch), in North-Central Mexico. In autumn 2003 and spring 2004, two glasshouse experiments were carried out to assess the influence of that mite on the concentration of total soluble sugars and starch in leaves, bark and roots of 'diamante mejorado' peach trees. Apical leaves of peach trees were inoculated with three mite densities per leaf: (A) 10-20, (B) 21-40, (C) 41-80; a mite-free control was added. In 2003, at 81 days after infestation (DAI), cumulative mite-days per leaf (CMD) were 153, 1313, 2844 and 4771 in control and treatments (A), (B) and (C), respectively. In the same order, these CMD caused reductions in total soluble sugars (TSS): in leaves, 45, 50 and 61%; in bark, 9, 20 and 33%; in roots, 8, 20 and 26%. Reductions of starch concentration in leaves were 17, 43 and 56%; in bark, 25, 55 and 32%; in roots, 17, 22 and 32%. In 2004, at 77 DAI and 57, 1043, 2426 and 3996 CMD for control and treatments (A), (B) and (C), respectively, resulting reductions of TSS were: in leaves, 3, 7 and 15%; in bark, 0.8, 3 and 5%; in roots, 57, 60 and 78%, whereas reductions in starch concentration were: in leaves, 30, 34 and 44%; in bark, 18, 24 and 41%; in roots, 17, 47 and 48%. The higher reductions in roots found in 2004 are attributed to cumulative injury affecting food reserves.

Sperm allocation and cost of mating in a tropical tephritid fruit fly.

Males that copulate repeatedly may suffer from reduced sperm stores. However, few studies have addressed sperm depletion from both the female and male perspective. Here, we show that male Anastrepha obliqua (Diptera: Tephritidae) do not ejaculate all available sperm and are left with mature sperm in the seminal vesicles even after copulating as often as three times in half a day. Ejaculate size was not related to male mating history; time elapsed since the last mating, copulation duration, female thorax length or head width. Larval host origin did not affect the number of sperm stored by females. More sperm was found in the ventral receptacle compared to sperm stored in the three spermathecae. Males apparently do not suffer a cost of mating in terms of longevity, although we cannot rule out other fitness costs. Sperm production in this species may not be as costly as it is for other species. Results suggest that males strategically allocate similar numbers of sperm among successive mates without exhausting sperm reserves for future encounters. We discuss the role that differential sperm storage may have in mediating sperm competition and tie our results to the unique natural history of A. obliqua.