Water vapor pressure deficit in Portugal and implications for the development of the invasive African citrus psyllid trioza erytreae

African citrus psyllid (Trioza erytreae (Del Guercio)) is a vector insect of the bacterium Candidatus Liberibacter africanus, the putative causal agent of Huanglongbing, the most devastating citrus disease in the world. The insect was found on the island of Madeira in 1994 and in mainland Portugal in 2015. Present in the north and center of the country, it is a threat to Algarve, the main citrus-producing region. Trioza erytreae eggs and first instar nymphs are sensitive to the combination of high temperatures and low relative humidity. Daily maximum air temperature and minimum relative humidity data from 18 weather stations were used to calculate the water vapor pressure deficit (vpd) from 2004 to 2018 at various locations. Based on the mean vpd and the number of unfavorable days (vpd < 34.5 and vpd < 56 mbar) of two time periods (February to May and June to September), less favorable zones for T. erytreae were identified. The zones with thermal and water conditions like those observed in the Castelo Branco and Portalegre (Center), Beja (Alentejo), Alte, and Norinha (Algarve) stations showed climatic restrictions to the development of eggs and first instar nymphs of African citrus psyllid. Effective control measures, such as the introduction and mass release of Tamarixia dryi (Waterson), a specific parasitoid, and chemical control are necessary in favorable periods for T. erytreae development, such as in spring and in areas with limited or no climate restrictions.info:eu-repo/semantics/publishedVersio

AVALIAÇÃO DO DANO DA LAGARTA DO CARTUCHO EM MILHO BT E CONVENCIONAL

Introdução: Graças aos avanços tecnológicos em melhoramento genético à cultura do milho tem apresentado considerável aumento em potencial produtivo, destacando-se no Brasil a biotecnologia das sementes transgênicas, as quais são resistentes ao dano de alguns insetos e tolerantes a aplicações de herbicidas. O cultivo de milho geneticamente modificado que expressam toxinas de Bacillus thuringiensis aliado a inseticidas têm sido as duas principais medidas de controle de Spodoptera frugiperda, conhecida popularmente como lagarta do cartucho. Objetivo: Assim, objetivou avaliar o dano de S. frugiperda e a produção de milho Nidera NS50PRO que expressa as toxinas Cry1A.105 e Cry2Ab2 e convencional Biomatrix BM207, com três aplicações de inseticidas a base de lambda-cialotrina, clorpirifós e B. thuringiensis. Metodologia: O experimento foi realizado entre março e julho de 2019 em Uberlândia MG. Adotou-se delineamento experimental de blocos casualizados com oito tratamentos, em esquema fatorial 2x4 e quatro repetições, o fator cultivar com dois níveis (milho Bt e convencional) e o fator inseticida com quatro níveis (3 inseticidas e testemunha). O dano de S. frugiperda foi avaliado pela escala de Davis e Willians e índice de plantas danificadas. Componentes de produção: comprimento da espiga, diâmetro da espiga, número de fileiras de grãos na espiga, peso individual de espigas, produção de grãos, massa de 100 grãos foram avaliados. Considerações Finais: O dano de S. frugiperda foi menor no milho Bt, sendo as variáveis diâmetro de espiga, peso de espiga, produção e massa de 100 grãos maiores no cultivar Bt. Os inseticidas lambda-cialotrina, clorpirifós e B. thuringiensis não reduziram o dano de S. frugiperda em milho convencional Biomatrix BM207. No milho Bt NS50PRO o inseticida lambda-cialotrina aumentou a massa de 100 grãos

Natural parasitism of the Citrus Leafminer (Lepidoptera: Gracillariidae) over eight years in seven citrus regions of São Paulo, Brazil

The 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.A minadora das folhas dos citros (MFC), Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae), foi encontrada pela primeira vez no Brasil em 1996. Em 1998, o parasitoide Ageniaspis citricola Logvinovskaya (Hymenoptera: Encyrtidae) foi introduzido e se estabeleceu em várias regiões do país. Nesse estudo, foram feitas130 amostragens, de uma hora, de folhas de laranjeiras doces [Citrus sinensis (L.) Osbeck] com câmaras pupais da MFC, para se estimar o parasitismo da MFC em 7 regiões do estado de São Paulo, entre 2000 e 2008. O tamanho das amostras variou de 10 a 275 folhas (média = 65). O parasitoide mais abundante foi o encirtídeo A. citricola (encontrado em 91.8% das amostragens). O maior parasitismo da MFC por A. citricola foi observado na região sul do estado (Botucatu), 70,2 ± 6,6 (média ± EPM), e o menor parasitismo na região norte (Barretos), 12,8 ± 5,7%. O parasitismo da MFC por A. citricola e seus parasitoides nativos (Galeopsomyia fausta LaSalle, Cirrospilus spp. and Elasmus sp.) não diferiram entre as estações do ano. O aumento de seis vezes no uso de inseticidas nos pomares de citros, após 2004, quando o Huanglongbing (HLB) foi encontrado no estado de São Paulo, não reduziu o nível de parasitismo da MFC. O nível médio de parasitismo foi de 50,8 ± 4,2%, antes do HLB (2000-2004), e 56,0 ± 4,4%, após o HLB (2005-2008), indicando a adaptação de A. citricola a um agroecossistema perturbado.info:eu-repo/semantics/publishedVersio

SEED GERMINATION AND PRODUCTION OF SWAMP PALM SEEDLINGS (Mauritia flexuosa L.f.)

ABSTRACT Swamp palm (Mauritia flexuosa L.f.) is a typical palm tree from the Amazon and Cerrado of Brazil, whose fruits are used in cooking and the pharmaceutical industry. Seed germination of this palm is slow, irregular and often low, which makes its cultivation limited, being exploited in extractive systems. Also, little is known about seedling development, and this knowledge is important to define a protocol for the production of seedlings of this species. This research aimed to develop a protocol for the seed germination of swamp palm under semi-aseptic conditions and to evaluate the seedling development of swamp palm under different production systems. There was no germination in treatments without scarification. The best germination protocol for swamp palm was scarification with operculum removal in seeds recently extracted from the fruit with application of gibberellic acid (plant growth regulator) because it increased the rate and accelerated germination. However, imbibition in aerated water (with H2O2) proved to be suitable up to two days. The best method for seedlings production of swamp palm is the use of conventional bag (20×30 cm) with soil and manure or for producers with greater investment capacity, the use of tubes (180 cm3) for two months and subsequent transplanting to a conventional bag with soil and manure until completing six months

Electrical conductivity of complete and commercial nutrient solutions in tube-based passion fruit seedling production

ABSTRACT: Fertigation is widely used in seedling production for different crops, including passion fruit. There is no consensus on the ideal nutrient solution, and as such, nurseries have used fertigation empirically. This study assessed the electrical conductivity of nutrient solution containing macro and micronutrients in passion fruit seedling production and compared it with commercially used fertigation. A completely randomized design was used, with five treatments and six repetitions. Four electrical conductivities (0.5, 1.0, 2.0 and 4.0 dS m-1) of a complete nutrient solution and an additional treatment (commercial nutrient solution) were analyzed. Daily fertigation with a complete nutrient solution (macro and micronutrients) at electrical conductivities between 2.6 and 3.3 dS m-1 followed by two daily irrigations are efficient at producing FB 300 “Araguari” passion fruit seedlings in coconut fiber substrate, with benefits such as greater biomass and better Dickson quality index when compared to commercial nutrient solution

Hidrogenionic potential (pH) of the attractant, trap density and control threshold for Ceratitis capitata (Diptera: tephritidae) on Hamlin oranges in São Paulo central region, Brazil

This 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.Esta pesquisa teve como objetivos: avaliar o efeito do pH inicial, 4.5; 6.5 e 8.5, do atrativo proteico Milhocina® e bórax (tetraborato de sódio) na captura de moscas-das-frutas em armadilhas McPhail; estudar densidades de armadilhas, 1; 2; 4 e 8 por hectare, para estimar níveis de controle em laranja cv. Hamlin, na região central de São Paulo. A espécie predominante, com 99% das moscas-das-frutas capturadas, foi Ceratitis capitata, sendo 80% de fêmeas. As maiores capturas de C. capitata ocorreram nas armadilhas com Milhocina® e bórax em pH 8.5. As capturas, nas 4 densidades, foram semelhantes, indicando que a população pode ser estimada com uma armadilha por hectare em áreas de altas populações. Houve relações positivas entre capturas de C. capitata e o número de frutos danificados, 2 e 3 semanas após a captura. Assim, foram obtidas equações que relacionam a captura e o dano, possibilitando estimar níveis de controle desse inseto. As perdas médias causadas por C. capitata em laranja cv. Hamlin chegaram a 2,5 toneladas de frutos por hectare ou 7,5% da produção.info:eu-repo/semantics/publishedVersio

Fruit flies in orange groves: trap density for monitoring, effect of attractant ph and establishiment of an action threshold level.

Este trabalho teve por objetivos: avaliar o efeito do pH inicial e o tempo de permanência no campo do atrativo alimentar Milhocina® com o conservante bórax (tetraborato de sódio) na captura de moscas-das-frutas em armadilhas do tipo McPhail; estudar densidades de armadilhas para monitoramento de moscas-das-frutas e determinar um nível de dano e de controle em cultura de laranja. Foram realizados três experimentos de campo, o primeiro em junho de 2002 em pomar de laranja de maturação precoce, cultivar Hamlin, em Itaju, região central do estado de São Paulo, para se avaliar a captura de moscas-das-frutas em armadilhas com os atrativos Milhocina® em pH 4,5, Milhocina® com bórax em pH 4,5, 6,5 e 8,5, aos 2, 4, 6 e 8 dias após a instalação no pomar. O segundo experimento foi desenvolvido de junho a agosto de 2002 (inverno seco) com laranja Hamlin em Itaju, e o terceiro experimento foi realizado de janeiro a março de 2003 (verão chuvoso) com laranja de maturação tardia, cultivar Natal, em Porto Feliz, região sul do estado, ambos para se avaliar as densidades de uma, duas, quatro e oito armadilhas por hectare e a relação entre a captura de moscas-das-frutas nas armadilhas e frutos danificados. Em Itaju, as maiores capturas de Ceratitis capitata (Wiedemann, 1824) ocorreram nas armadilhas com o atrativo protéico Milhocina® e bórax em pH 8,5, aos 2, 4 e 6 dias. A espécie predominante, com quase 99% das moscas-das-frutas capturadas, foi C. capitata, sendo a proporção de fêmeas capturadas de 80% em pomar com frutos e 46% em pomar sem frutos. As capturas de fêmeas, machos, e total (fêmeas e machos) de C. capitata por armadilha, nas densidades de uma, duas, quatro e oito armadilhas por hectare, foram semelhantes, indicando que C. capitata pode ser monitorada com uma armadilha por hectare em áreas de altas populações de moscas. Houve correlações entre a captura de fêmeas, e fêmeas e machos de C. capitata, e o número de frutos de laranja precoce Hamlin danificados, sete e quatorze dias após a coleta, nas densidades de uma e duas armadilhas por hectare. Foram obtidas equações que relacionam a captura com o dano. Assim, para um dano de um fruto por árvore, o nível de controle poderia ser de 8 a 16 indivíduos de C. capitata por armadilha por dia. As perdas médias estimadas devido ao ataque de C. capitata em laranja precoce chegaram a 2,5 toneladas de frutos por hectare, ou 7,5% da produção. Em Porto Feliz, onde predominou Anastrepha fraterculus (Wiedemann, 1830), as capturas foram baixas e o dano foi observado mais freqüentemente não sendo correlacionado com as capturas de moscas-das-frutas nas armadilhas.This research aimed to evaluate the effect of different levels of pH and the exposure time of the trap in the field, baited with Milhocina® and borax (sodium borate), on capturing fruit flies, to study different densities of McPhail trap for monitoring fruit flies and to establish the relation between fruit fly catches in traps and damaged orange fruits to determine injury and action threshold levels for fruit flies in orange groves. Three field experiments were carried out: the first one conducted in June of 2002 in a Hamlin orange grove in Itaju, central region of state of Sao Paulo, to evaluate the trap with Milhocina® as attractant at pH 4.5 and Milhocina® and borax at pH 4.5, 6.5 and 8.5. Counts of fruit fly numbers were done at 2, 4, 6 and 8 days after placing the trap in the orange grove. The second experiment was conducted from June to August of 2002 (during dry winter) in a Hamlin orange grove in Itaju, and the third one was conducted from January to March of 2003 (during rainy summer) in a Natal orange grove in Porto Feliz, in southern region of state of Sao Paulo, both to evaluate the densities of one, two, four and eight traps per hectare and to study the relationship between fruit fly catches in the traps and damaged fruits. In Itaju, the highest catches of Ceratitis capitata (Wiedemann, 1824) were observed in traps baited with Milhocina® and borax at pH 8.5 after 2, 4 and 6 days. The most abundant fruit fly species was C. capitata, comprising almost 99% of the fruit flies captured, and the proportion of female catches was 80% in groves with fruits and 46% in groves without fruits. The fruit fly catches per trap were similar at different trap densities, indicating that C. capitata could be monitored by using one trap per hectare in areas with high fruit fly populations. Significant linear correlations were observed between females, males and females catches and damaged fruits in the following week and one week later, at densities of one and two traps per hectare. The action threshold level estimated ranged from 8 to 16 C. capitata per trap per day for one damaged fruit per tree. The mean estimated damage caused by C. capitata in Hamlin orange was 2,500 kg of fruits per hectare which corresponds to 7.5% of the total yield. Anastrepha fraterculus (Wiedemann, 1830) was the predominant species in Porto Feliz. In this experiment, the fruit fly catches were low, the intensity of damaged fruits was higher and there was no correlation with fruit fly catches in the traps

Spatial and seasonal distribution, natural enemies and ecological life table of Diaphorina citri Kuwayama (Hemiptera: Psyllidae) in citrus groves in São Paulo

O \"huanglongbing\" (HLB), ou \"greening\" dos citros, tem sido considerada a pior e mais destrutiva doença que ocorre em cultivares comerciais de citros do mundo. Até hoje, não se conhecem medidas eficientes para o controle da doença. Apesar disso, são recomendadas três medidas que podem reduzir a disseminação da mesma, (1) propagação de material sadio, (2) eliminação de planta sintomática tão logo seja constatada e (3) redução da população do vetor, o psilídeo Diaphorina citri Kuwayama. O HLB foi constatado no Brasil, no estado de São Paulo, em março de 2004. Desde então, foram constatadas duas bactérias associadas a plantas com sintomas, \"Candidatus Liberibacter americanus\" e \"Candidatus Liberibacter asiaticus\", ambas transmitidas por D. citri. A proposta deste trabalho foi estudar: (1) a distribuição temporal deste inseto em pomares comerciais de laranja (Citrus sinensis) nas regiões de Araras, Bauru, Botucatu, Casa Branca, Lins e São Carlos, estado de São Paulo, no período de julho de 2004 a junho de 2007, (2) a distribuição espacial de D. citri em Bauru, Botucatu, Franca, Lins e São Carlos com base na relação variância/média, coeficiente de Taylor e índice de Morisita, (3) inimigos naturais de D. citri e taxas de parasitismo de ninfas do psilídeo por Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) em diferentes pomares, no período de 2005 a 2007 e (4) a tabela de vida ecológica das fases imaturas deste inseto, em Araras e Piracicaba, por quatro gerações. As proporções de ramos de C. sinensis infestados por ninfas e adultos do psilídeo variaram de 0 a 68,3% e se mostraram dependentes da disponibilidade de ramos em crescimento (novos), embora o tamanho da população seja dependente do clima. A maior infestação de ninfas foi observada em São Carlos e as maiores infestações de adultos ocorreram em Bauru, Botucatu, Lins e São Carlos. Por outro lado, as menores proporções de ramos infestados foram observadas em Araras e Casa Branca. D. citri mostrou uma distribuição do tipo agregada, tanto para a fase ninfal quanto para a fase adulta. Não foram observados coccinelídeos predando ovos ou ninfas do psilídeo. A predação de D. citri por crisopídeos foi muito baixa nas condições estudadas. As taxas médias de parasitismo de ninfas, de quarto e quinto ínstares, por T. radiata variaram entre as áreas amostradas e épocas, de 0 a 91,6%, sendo tal parasitismo variável de acordo com a cultivar de citros. Na tabela de vida ecológica, verificou-se que as durações do período de ovo a adulto, em campo, foram semelhantes entre as quatro gerações, de 18,0 a 24,7 dias (temperaturas médias de 21,6 a 26,0°C) e seguiram os modelos de exigências térmicas do inseto obtidos em laboratório. Entretanto, as viabilidades deste mesmo período variaram consideravelmente, de 1,7 a 21,4%, sendo que as maiores mortalidades foram verificadas nas fases de ovo e ninfa pequena (primeiro a terceiro ínstares), as quais são consideradas fatores chaves para o crescimento populacional da praga.Huanglongbing (HLB), or citrus greening disease, has been considered the worst and most destructive disease that occurs in all citrus varieties in the world. Until today, effective control measures are unknown. However, three main measures have been recommended that may reduce the spread of the disease: (1) propagation of healthy plants; (2) elimination of symptomatic trees as soon as they are observed; and (3) reduction of the insect vector population, the citrus psylla Diaphorina citri Kuwayama. HLB was first found in Brazil in the State of São Paulo in March 2004. Since then, two bacteria were found associated with plants with symptoms, \"Candidatus Liberibacter americanus\" and \"Candidatus Liberibacter asiaticus\", both transmitted by D. citri. This research aimed to study: (1) the seasonal distribution of D. citri in citrus groves (Citrus sinensis) in Araras, Bauru, Botucatu, Casa Branca, Lins and São Carlos, State of São Paulo, from July 2004 through June 2007; (2) the spatial distribution of D. citri in Bauru, Botucatu, Franca, Lins and São Carlos according to the variance/mean ratio, Taylor\'s power law coefficients, and Morisitas index; (3) natural enemies of D. citri and parasitism rates of citrus psylla nymphs by Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) in different groves in three years, 2005, 2006, and 2007; and (4) the ecological life table of the immature stages of this insect, in Araras and Piracicaba, over four generations. The proportions of C. sinensis flushes or branches infested with nymphs and adults of citrus psylla ranged from 0 to 68.3%, and were dependent on the availability of new flushes, although population size depends on the climate. The largest infestation of nymphs was observed in São Carlos and the largest infestations of adults occurred in Bauru, Botucatu, Lins, and São Carlos. On the other hand, the lowest proportions of infested flushes or branches were observed in Araras and Casa Branca. D. citri nymphs and adults showed an aggregate distribution. No coccinellids were observed preying on eggs and nymphs of D. citri. Predation of D. citri by lacewings was very low under the conditions studied. The average parasitism rates of fourth- and fifth-instar nymphs by T. radiata varied among the sampled areas and seasons from 0 to 91.6%, and also varied with citrus variety. In the ecological life table, the mean developmental period from egg to adult in the field was similar between the four generations, 18.0 to 24.7 days (average temperatures of 21.6 to 26.0°C) and values were not different from the thermal requirement models obtained in the laboratory. However, immature survival ranged considerably, from 1.7 to 21.4%, and the highest mortalities were observed in eggs and small nymphs (first to third instars), which are considered the key factors for population growth of the pest

Natural parasitism of Diaphorina citri Kuwayama (Hemiptera, Psyllidae) nymphs by Tamarixia radiata Waterston (Hymenoptera, Eulophidae) in S\ue3o Paulo orange groves

Natural parasitism of Diaphorina citri Kuwayama (Hemiptera, Psyllidae) nymphs by Tamarixia radiata Waterston (Hymenoptera, Eulophidae) in Sao Paulo orange groves. The psyllid Diaphorina citri Kuwayama 1908 has become the main citrus pest species in the state of Sao 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, Jau, Limeira, Lins and Sao Joao 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 Sao 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