perennial breeding species demand substantial investment in various resources, mainly the required time to obtain adult and productive plants. estimating several genetic parameters in these species, in a more confidence way, means saving resources when selecting a new genotype. A model using the Bayesian approach was compared with the frequentist methodology for selecting superior genotypes. A population of 17 families of full-siblings of guava tree was evaluated, and the yield, fruit mass, and pulp mass were measured. The Bayesian methodology suggest more accurate estimates of variance components, as well as better results to fit of model in a cross-validation. Proper priori for Bayesian model is very important to convergency of chains, mainly for small datasets. Even with poor priori, Bayesian was better than frequentist approach.

ABSTRACT. Lasiodiplodia theobromae is a plant pathogen with a worldwide distribution, with low host specificity, causing stem cankers, dieback diseases, and fruit rot in several species of plants. In coconut, this pathogen is reported as the etiological agent of "coconut leaf blight" (CLB) disease, causing several losses in fruit production. The CLB is an important disease for this crop in Brazil. In our study, we used a phylogeographic approach through the molecular characterization of the translation elongation factor 1-α (TEF1-α) to elucidate the pathogen distribution in Brazil and other countries, besides, search information about diversity sources of this pathogen in coconut palm tree at Brazilian northern, northeast, and southeast. We found that L. theobromae diversity is within populations (locations), and populations that are located closest to the center of the tropical zone have more variability as Central Africa, Brazilian Southeast, and Northeast. The widespread distribution could be in part related with long-distance dispersal via global trade of plants and plant products. The entrance route of L. theobromae in Brazil probably occurred from Africa route and not occurred once. In Brazil, the diversity of this pathogen in coconut tree could be linked to two agents of selection: high host diversity (in Northeast) and distinct management measures adopted in Southeast. These different sources of selection, mainly the mutations, could be one of the reasons that we found distinct reactions to "coconut leaf blight" chemical control in these regions.

One of the major bottlenecks in the postharvest commercialization of coconut fruits is the black rot disease, caused by the fungus Ceratocystis paradoxa. This disease has been neglected in the main production areas or associated with other coconut diseases. To date, there are no standardized methods for assessing the intensity of such a problem. In this sense, the aim of our study was to prepare and validate a diagrammatic scale to evaluate the disease severity in coconut fruits. We also tested the scale applicability comparing distinct C. paradoxa isolates on inoculated fruits. ABSTRACT quantification, the fruit longitudinal sectioning was necessary, allowing the visualization of internal symptoms. The proposed scale showed good repeatability and high reproducibility, with absolute errors around 8%, while the coefficient of determination presented an average of 91% with the aid of the scale and of 59% without the scale. In addition, symptom analyses showed that the outer necrosis does not match the internal damage. Therefore, we suggest in this study that the severity estimate of this disease be obtained by using the presented scale. RESUMOUm dos principais problemas na comercialização de frutos de coco em pós-colheita tem sido a podridão negra, causada pelo fungo Ceratocystis paradoxa. Esta doença tem sido negligenciada nas principais áreas produtoras ou associadas à outras doenças da cultura. Até o presente momento, não existem métodos padronizados para a avaliação da intensidade de tal problema. Neste sentido, o objetivo do nosso estudo foi preparar e validar uma escala diagramática para avaliar a severidade da doença em frutos de coco. Com isso, foi possível testar a aplicabilidade da escala comparando diferentes isolados de C. paradoxa em Santos, P.H.D.; Mussi-Dias, V.; Freire, M.G.M.; Carvalho, B.M.; Silveira, S.F. Escala Diagramática para avaliação da severidade da podridão negra (Ceratocystis paradoxa) na pós colheita em coco. Summa Phytopathologica, v.43, n.4, p.269-275, 2017. frutos inoculados. Para esta quantificação, o seccionamento longitudinal do fruto foi necessário, permitindo a visualização interna dos sintomas. Dessa forma, a escala proposta apresentou boa repetibilidade e alta reprodutibilidade, com erros absolutos em torno de 8% e coeficientes de determinação com médias de 91% com o auxílio da escala e de 59% sem a escala. Além disso, as análises sintomáticas mostraram que uma necrose exterior não corresponde ao dano interno. Por isso, indica-se neste trabalho, a estimativa da severidade desta doença através da escala apresentada.

Leaf blight disease in coconut (LBC) caused by Lasiodiplodia theobromae leads to early defoliation and loss of bunches, which negatively impacts coconut fruit yield. The etiology of LBC in Brazil needs to be updated based on modern tools such as DNA sequencing and phylogenetic analysis. A phylogenetic tree using ITS and TEF-1α genes in combination with morphology showed L. theobromae as the most common species associated with LBC in Brazil. We identified six species from distinct plant parts (leaves, fruits, rachis, inflorescence, stem and stipe): L. brasiliense, L. pseudotheobromae, L. laeliocattleyae, Botryosphaeria fabicerciana and B. dothidea. Our pathogenicity test results revealed that B. fabicerciana and L. pseudotheobromae cause LBC symptoms. Our study is the first to address two species, in addition to L. theobromae, as etiologic agents of LBC disease based on morphological, phylogenetic and pathogenicity data.

To find control forms alternative to fungicides, this study aimed to evaluate the effect of products with potential to control black spot (Asperisporium caricae) in different papaya genotypes. Installed in a greenhouse, the experiment was conducted in randomized blocks (RB) with factorial arrangement 5x6, three replicates, and spraying of four products (Bion®, Bordeaux mixture, Ecolife®, and Bordasul®) in six papaya genotypes (‘Sunrise Solo PT’, ‘STZ 03’, ‘Golden’, ‘Tailândia’, ‘Maradol’ and ‘UENF-CALIMAN 01’), while control was sprayed only with water. The severity (BSS) and the incidence (BSI) of black spot on the leaves were quantified, as well as the area under the disease progress curve (AUDPC). There was variability among the evaluated genotypes, highlighting ‘STZ 03’, ‘Maradol’ and ‘UENF/CALIMAN 01’ as the most resistant genotypes. ‘Tailândia’ (susceptible) showed greater response to the products. Plants sprayed with Bion®, Bordeaux mixture and Bordasul® had reduced black spot means.

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Abstract:In support of breeding of papaya (Carica papaya) 'Caliman M5', 'GTF', and 'JS 11'. In the greenhouse experiment, the genotypes 'Caliman M5', 'Golden', 'Kapoho Solo', 'Waimanalo', 'Mamão Bené', 'JS 12', and 'GTF' had the lowest mean incidence in at least one evaluation. On the other hand, for severity, the genotypes 'Diva', 'Sunrise Solo 72/12', 'Kapoho Solo PA', 'Waimanalo', 'Maradol', 'Maradol GL', 'FMV, had the lowest means. These results indicate these genotypes for a possible use in breeding for reduction of powdery mildew intensity.

The antifungal activity of fungi with biocontrol potentials should be studied. Therefore, this study aimed at establishing alternative agent to replace the chemical control of papaya black spot. We investigated the antagonistic activity of the fungi Hansfordia pulvinata (H-611), Acremonium sp (A-602, A-617 and A-598), Simplicillium lanosoniveum (S-599), Lecanicillium lecanii (L-622), and Sarocladium implicatum (I-609) on the phytopathogenic fungus A. caricae, by evaluating the mycoparasitism, the enzymatic activity and the production of volatile and non-volatile compounds. For the evaluation of mycoparasitism, each antagonic fungi isolate was microcultured along with conidia of A. caricae. Then, events of mycoparasitism were evaluated at 24h, 48h, 72h, and 96h after inoculation under an optical microscope. We estimated the enzymatic activity (protease and lipase) of the fungi in a particular culture medium for each enzyme. The activity of the protease was reflected in the mean diameter of the halo. The lipase activity was measured by the halo/colony relation. In order to detect volatile compounds in the antibiosis test, A. caricae was cultured under a medium along with the isolates described. For the test of non-volatile compounds, we evaluated the germination of A. caricae in culture medium by diffusion under cellophane paper. As a result, the mycoparasitism of the H-611, A-602, A-617, A-598, S-599, and L-622 isolates was confirmed on the microcultures. We observed higher activities of protease in the I-609, S-599, A-602, and A-598 isolates. The H-611 and A-602 isolates presented higher activities for lipase. We did not observe effect of volatile compounds in any of the tested isolates. In the non-volatile compound test, there was production of antifungal metabolite highlighting the A-617 isolate, which inhibited the germination of the conidia of A. cariae by 100%.