Reação de genótipos de pessegueiro a mancha foliar causada por Xanthomonas arboricola pv. pruni

A bacteriose foliar causada por Xanthomonas arboricola pv. pruni é uma das mais importantes doenças do pessegueiro [Prunus persica (L.) Batsch] no Brasil e no mundo. Avaliou-se a sensibilidade de genótipos de pessegueiro a X. arboricola pv. pruni. Trinta genótipos foram avaliados em campo, quanto à incidência, severidade e desfolha causada pela bactéria. Calculou-se a correlação entre desfolha e severidade da doença. A partir dos resultados obtidos em campo, foram selecionados quatro genótipos resistentes ('Conserva 985', 'Conserva 871', 'Conserva 1129' e 'Tropic Snow') e quatro suscetíveis ('Conserva 1153', 'Bonão', 'Conserva 1125' e 'Atenas') para serem novamente avaliados pelo bioensáio com folhas destacadas e em casa de vegetação. Os genótipos diferiram quanto a reação ao patógeno, não sendo observada imunidade. Confirmou-se a resistência para 'Conserva 985' e 'Conserva 1129' e a suscetibilidade para 'Conserva 1153', 'Conserva 1125' e 'Atenas', pelo bioensáio com folhas destacadas.Bacterial leaf spot (BLS), caused by Xanthomonas arboricola pv. pruni, is one of the most important diseases in Brazilian peach [Prunus persica (L.) Batsch] orchards and all over the world. The main objective of this study was to evaluate for BLS sensitivity of peach genotypes. Evaluations of thirty genotypes were carried out during the onset of the disease, for incidence, severity and defoliation, in field conditions. Pearson's correlations between the percentage of defoliation and leaf severity rating were performed. Genotypes 'Conserva 985', 'Conserva 871', 'Conserva 1129', and 'Tropic Snow', as resistance sources, and 'Conserva 1153', 'Bonão', 'Conserva 1125', and 'Atenas', as susceptible to BLS, were submitted to detached-leaf bioassay and greenhouse evaluation. The peach genotypes showed different reactions to the BLS, and none was immune to the pathogen. 'Conserva 985' and 'Conserva 1129' confirmed resistance responsiveness while 'Conserva 1153', 'Conserva 1125' and 'Atenas' were found susceptible for the detached-leaf bioassay

Chilling privation during dormancy period and carbohydrate mobilization in Japanese pear trees

The flower bud abortion is one of the main problems that limit commercial pear (Pyrus pyrifolia) production in the southern region of Brazil. Insufficient chilling during the dormancy period is known as the main factor of this problem. One of the hypotheses to explain this problem is that the starch mobilization and carbohydrate fluxes to the buds are impeded when mild temperatures occurred during winter. This study compared the total soluble sugars (TSS) and reducing sugars (RS) concentrations, the cell wall acid invertase (CWAI - EC 3.2.1.26) and sucrose-phosphate synthase (SPS - EC 2.4.1.14) activities in wood of branches and floral buds of Japanese pear trees cv. Housui, grafted on Pyrus calleryana and submitted to chilling conditions during the dormancy period. Treatments were: (i) natural conditions; (ii) continuous artificial chilling; (iii) alternating temperatures, and (iv) total chilling privation. TSS and RS contents, as well as CWAI and SPS activities in tissues of branches that received insufficient chilling were lower than those that received sufficient chilling during winter. The starch concentration was superior in wood tissues of branches kept under chilling privation. The chilling privation disturbs carbohydrate mobilization in pear trees, reducing the sucrose synthesis capacity in wood tissues (source) and sucrose importation by the floral buds (sink)

Chilling privation during dormancy period and carbohydrate mobilization in Japanese pear trees

The flower bud abortion is one of the main problems that limit commercial pear (Pyrus pyrifolia) production in the southern region of Brazil. Insufficient chilling during the dormancy period is known as the main factor of this problem. One of the hypotheses to explain this problem is that the starch mobilization and carbohydrate fluxes to the buds are impeded when mild temperatures occurred during winter. This study compared the total soluble sugars (TSS) and reducing sugars (RS) concentrations, the cell wall acid invertase (CWAI - EC 3.2.1.26) and sucrose-phosphate synthase (SPS - EC 2.4.1.14) activities in wood of branches and floral buds of Japanese pear trees cv. Housui, grafted on Pyrus calleryana and submitted to chilling conditions during the dormancy period. Treatments were: (i) natural conditions; (ii) continuous artificial chilling; (iii) alternating temperatures, and (iv) total chilling privation. TSS and RS contents, as well as CWAI and SPS activities in tissues of branches that received insufficient chilling were lower than those that received sufficient chilling during winter. The starch concentration was superior in wood tissues of branches kept under chilling privation. The chilling privation disturbs carbohydrate mobilization in pear trees, reducing the sucrose synthesis capacity in wood tissues (source) and sucrose importation by the floral buds (sink)

Enzimas associadas a indução de resistência em morangueiro pelo uso de quitosana e acibenzolar-s-metil

A indução de resistência em plantas a patógenos  com a utilização de indutores   está sendo amplamente estudada considerando a demanda por frutos  mais saudáveis. O objetivo deste trabalho foi avaliar a atividade de enzimas associadas a indução de resistência em morangueiro pelo uso de quitosana e  Acibenzolar-S-Metil (ASM). O delineamento experimental foi de blocos ao acaso com 16 plantas por parcela e cinco repetições. Os tratamentos foram quitosana (1,0%); ASM (0,0025%), com aplicação de fungicidas e à testemunha (água destilada). A aplicação dos tratamentos ocorreu 45 dias após o plantio das mudas de morangueiro cv. Aroma e as amostras foliares foram coletadas 24, 72, 120 e 168 h após a aplicação dos mesmos. As PRs-proteinas quitinase e b-1,3-glucanase são ativadas pelo uso dos indutores, sendo a b-1,3-glucanase pronunciada nas primeiras 120 horas após a aplicação dos indutores  e a quitinase a partir de 168 horas da indução.

‘Cerejeira da mata’ and ‘guabijuzeiro’ propagation by air layering

‘Guabijuzeiro’ and ‘cerejeira da mata’ are plant species from the Myrtaceae family, with many difficulties in asexual multiplication. Thus, the aim of this study was to evaluate ‘cerejeira da mata’ (Eugenia involucrata DC.) tree and ‘guabijuzeiro’ [Myrcianthes pungens (Berg) Legrand] tree propagation by air layering, using different IBA concentrations (0, 1000 , 2000 and 3000 mg L-1) and materials to wrap the substrate (transparent plastic, black plastic and transparent plastic + aluminum foil). The experimental design for both experiments was a randomized blocks, in a 3 x 4 factorial (wrapping material x IBA concentration), with three repetitions of five air layering each. After 180 days, the percentage of rooting, length and number of roots were evaluated. Sixty days after rooting the percentage of survival plants were evaluated. The air layering technique was not efficient in the ‘guabijuzeiro’ propagation. This technique could be used in ‘cerejeira da mata’ plants without the IBA application and using transparent plastic, but with low performance.‘Guabijuzeiro’ and ‘cerejeira da mata’ are plant species from the Myrtaceae family, with many difficulties in asexual multiplication. Thus, the aim of this study was to evaluate ‘cerejeira da mata’ (Eugenia involucrata DC.) tree and ‘guabijuzeiro’ [Myrcianthes pungens (Berg) Legrand] tree propagation by air layering, using different IBA concentrations (0, 1000 , 2000 and 3000 mg L-1) and materials to wrap the substrate (transparent plastic, black plastic and transparent plastic + aluminum foil). The experimental design for both experiments was a randomized blocks, in a 3 x 4 factorial (wrapping material x IBA concentration), with three repetitions of five air layering each. After 180 days, the percentage of rooting, length and number of roots were evaluated. Sixty days after rooting the percentage of survival plants were evaluated. The air layering technique was not efficient in the ‘guabijuzeiro’ propagation. This technique could be used in ‘cerejeira da mata’ plants without the IBA application and using transparent plastic, but with low performance

Peach genotypes reaction to leaf rust

O objetivo deste trabalho foi identificar fontes de resistência à ferrugem-da-folha em pessegueiro. Foram realizadas três avaliações de incidência e severidade de ferrugem-da-folha em 15/1, 14/2 e 24/3 de 2005, em 17 genótipos; em 23/2/2006, a severidade foi avaliada em 12 genótipos e nos 17 já avaliados anteriormente; em 28/1/2008, avaliaram-se a incidência, a severidade e a desfolha nos 29 genótipos avaliados anteriormente, além de 'Conserva 803'; em 3/2/2008, avaliou-se o número de lesões por folha em 12 genótipos. Os dados de incidência, severidade, desfolha e número de lesões por folha, em cada ano, foram submetidos à análise de variância, e as médias dos genótipos foram comparadas pelo teste de Scott-Knott. Foram realizadas correlações de Pearson entre incidência, severidade, desfolha e lesões por folha (2008). Os dados de incidência, severidade e desfolha de 28/1/2008 e os de severidade de 23/2/2006 foram submetidos à análise multivariada. 'Olímpia' e 'Cascata 1063' apresentaram níveis aceitáveis de resistência à ferrugem-da-folha; não foi verificada imunidade à doença, mas sim eficiência de infecção diferenciada nos genótipos estudados, o que indica que o tipo de resistência encontrada pode ser horizontal. O número de lesões por folha pode ser usado para classificar genótipos de pessegueiro quanto à reação à ferrugem-da-folha.The objective of this work was to identify resistance sources to leaf rust in peach tree. Three evaluations of leaf rust incidence and severity were performed in 1/15, 2/14 and 03/24 of 2005 in 17 genotypes; severity was evaluated in 2/23/2006, in 12 genotypes and in the 17 ones previously evaluated; incidence, severity and defoliation were evaluated in 1/28/2008, in the 29 evaluated genotypes and in 'Conserva 803'; in 2/3/2008, lesions per leaf were determined in 12 genotypes. Analysis of variance was performed for incidence, severity, and lesions per leaf, for each year, and means were compared by Scott-Knott test. Pearson's correlation analyses were accomplished for incidence, severity, defoliation and lesion per leaf (2008). Data for incidence, severity and defoliation (1/28/2008) and severity (2/23/2006) were submitted to multivariate analysis. 'Olímpia' and 'Cascata 1063' showed acceptable levels of resistance to leaf rust; no immunity to leaf rust was detected; however, differential efficiency of infection among genotypes was observed, which indicates that the resistance could be horizontal; the number of lesions per leaf could be used to classify peach genotypes reaction to leaf rust

Herdabilidade de resistência de pessegueiro à bacteriose foliar

The objective of this work was to evaluate the broad-sense heritability reaction to bacterial leaf spot (Xanthomonas arboricola pv. pruni), in peach tree populations obtained from directed crosses. Disease severity and defoliation of the genotypes were evaluated in field conditions, with posterior measurement of the healthy leaf area duration (HAD). The observed average heritability (0.51) indicates that the use of the evaluated genitors can be effective for the development of cultivars with higher resistance to the disease.O objetivo deste trabalho foi avaliar a herdabilidade no sentido amplo da reação à bacteriose foliar (Xanthomonas arboricola pv. pruni), em populações de pessegueiro obtidas de cruzamentos dirigidos. A severidade da doença e a desfolha dos genótipos foram avaliadas em campo, com posterior mensuração da duração da área foliar sadia (HAD). A herdabilidade média observada (0,51) indica que a utilização dos genitores avaliados pode ser efetiva para o desenvolvimento de cultivares com maior resistência à doença

Packing, moisture and environment for conservation of ‘jabuticatree açu’ seeds during storage

The objective of this study was to evaluate the viability of ‘jabuticaree açu’ [Plinia cauliflora (DC.) Berg] seeds according to water loss and packaging conservation conditions. Two experiments were carried out at UTFPR - Dois Vizinhos Campus, Parana State, Brazil. For the first experiment, the seeds were submitted to the hydro conditioning process by soaking in water during 24 hours with subsequently storage in a BOD chamber at 25°C for 0, 12, 24, 36, 48, 60, 72, 84 and 96 hours. This experiment was conducted in a completely randomized design with four replications of 50 seeds each. For the second experiment the seeds were separated into three lots: PET® bottles with lids, kraft® paper bags at room temperature and in cold storage (6°C±1°C). Each lot was stored during 0, 5, 10, 15, 20, 25, 30, 60, 90, 120 and 150 days. The experiment was carried out in a completely randomized design, in a 3x11 factorial (storage location x storage period), with four repetitions of 50 seeds each. Plinia cauliflora seeds present storage capacity of 96 hours at room temperature without loss of germination capacity, when previous hydro conditioning was carried out. Storage using Pet® bottles at room temperature for up to 25 days allows seeds viability.The objective of this study was to evaluate the viability of ‘jabuticaree açu’ [Plinia cauliflora (DC.) Berg] seeds according to water loss and packaging conservation conditions. Two experiments were carried out at UTFPR - Dois Vizinhos Campus, Parana State, Brazil. For the first experiment, the seeds were submitted to the hydro conditioning process by soaking in water during 24 hours with subsequently storage in a BOD chamber at 25°C for 0, 12, 24, 36, 48, 60, 72, 84 and 96 hours. This experiment was conducted in a completely randomized design with four replications of 50 seeds each. For the second experiment the seeds were separated into three lots: PET® bottles with lids, kraft® paper bags at room temperature and in cold storage (6°C±1°C). Each lot was stored during 0, 5, 10, 15, 20, 25, 30, 60, 90, 120 and 150 days. The experiment was carried out in a completely randomized design, in a 3x11 factorial (storage location x storage period), with four repetitions of 50 seeds each. Plinia cauliflora seeds present storage capacity of 96 hours at room temperature without loss of germination capacity, when previous hydro conditioning was carried out. Storage using Pet® bottles at room temperature for up to 25 days allows seeds viability

Diagnostico ecogeográfico da ocorrência de jabuticabeiras nativas no sudoeste do Paraná

The jabuticaba tree is a native fruit specie of restrict occurrence in the southwest region of the state of Paraná, Brazil. This observation carried the hypothesis that jabuticaba trees have edafoclimatic preference. This study aimed to investigate the ecogeografic and edafoclimatic conditions of the sites of naturally occurrence of jabuticaba trees on southwest region of Parana, Brazil. The study was conducted at 14 sites of occurrence of jabuticaba tree. Were recorded 4,036 adult plants of the Plinia cauliflora specie, in 201.9 hectares in the Araucaria Forest Biome. The sites were located mostly between 650 and 850 m of altitude and the plants were located always in the highest part of the toposequence site with minus probability of frost. Jabuticaba trees that occur in sites with lower altitude and higher average annual temperature are bigger than others from occurrence in sites with higher altitude and lower temperature. The soils where the jabuticaba trees grow up were clayey, strongly acidic (pH almost 4.0), with high content of organic matter and iron, aluminum high-saturation, low levels of phosphorus and very low saturation of bases.A jabuticabeira é uma fruteira nativa de ocorrência não generalizada na região sudoeste do Paraná, o que leva à hipótese de que esta espécie apresenta algumas preferências edafoclimáticas. Este trabalho teve como objetivo investigar as condições ecogeográficas e edafoclimáticas dos ambientes de ocorrência natural da jabuticabeira na região sudoeste do Paraná. O estudo foi efetuado em 14 sítios de ocorrência dessa espécie. Foram registradas 4.036 plantas adultas pertencentes à espécie Plinia cauliflora, em 201,9 a de mata do Ecossistema Floresta com Araucária. Os sítios estão localizados predominantemente entre 650 e 850 m de altitude, e as plantas localizam-se sempre na parte mais alta da topossequência, local menos propenso à ocorrência de geadas. Jabuticabeiras que ocorrem em sítios de menor altitude e com maior temperatura média anual são maiores que aquelas em sítios de maior altitude e menor temperatura. Os solos onde ocorrem as jabuticabeiras são argilosos, fortemente ácidos (pH próximo a 4,0), com alto teor de matéria orgânica e ferro, alta saturação de alumínio, baixo teor de fósforo e muito baixo índice de saturação de bases