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The germination test is routinely used for evaluating physiological quality of seeds, but it has not been satisfactory, since it requires relatively long periods to obtain results. In this sense, there is the possibility to resort to vigor tests, although the absence of standardized methodologies has hindered your applicability and reproducibility. The goal of the present study was to establish a methodology for the tetrazolium test that is effective for evaluating physiological quality in pitaya seeds. So, we used five seed batches obtained from mature fruits of pitaya (Hylocereus undatus), harvested in the years of 2008, 2009, 2010, 2011, and 2012. The experimental design was the completely randomized design, with four replicates of 50 seeds. The tetrazolium test was conducted in a 5 × 4 × 3 factorial plot, corresponding to five batches of pitaya seeds (2008, 2009, 2010, 2011, and 2012), four concentrations of the tetrazolium solution (0.075%, 0.1%, 0.5%, and 1.0%) and three immersion periods (2, 3, and 4 h). In addition, the germination test for the seed batches was carried out and the analyzed variables were: percentage of germination (PG), germination speed index (GSI) and mean germination time (MGT). Data were submitted to ANOVA and means were compared by the Scott-Knott test (p ≤ 0.05). Tetrazolium test conducted at a solution concentration of 0.5% and an immersion period of 3 h proved to be efficient for evaluating physiological quality of pitaya seeds, in order to stratify the seed batches into more viability levels compared to the germination test.

Pitaya (Hylocereus undatus) is one of the most economic fleshy fruit tree crops. This study aimed at producing a high-density linkage genetic map of pitaya based on the whole genome resequencing (WGrS) approach. For this purpose, a bi-parental F1 population of 198 individuals was generated and genotyped by WGrS. High-quality polymorphic 6434 single polymorphism nucleotide (SNP) markers were extracted and used to construct a high-density linkage map. A total of 11 linkage groups were resolved as expected in accordance with the chromosome number. The map length was 14,128.7 cM with an average SNP interval of 2.2 cM. Homology with the sequenced reference genome was described, and the physical and genetic maps were compared with collinearity analysis. This linkage map in addition to the available genomic resources will help for quantitative trait mapping, evolutionary studies and marker-assisted selection in the important Hylocereus species.

Betalains are water-soluble nitrogen-containing pigments with multiple bioactivities. Pitayas are the only at large-scale commercially grown fruit containing abundant betalains for consumers. Currently, the key genes involved in betalain biosynthesis remain to be fully elucidated. Moreover, genome-wide analyses of these genes in betalain biosynthesis are not available in betalain-producing plant species. In this study, totally 53 genes related to betalain biosynthesis were identified from the genome data of Hylocereus undatus. Four candidate genes i.e., one cytochrome P-450 R gene (HmoCYP76AD1), two L-DOPA 4,5-dioxygenase genes (HmoDODAα1 and HmoDODAα2), and one cyclo-DOPA 5-O glucosyltransferase gene (HmocDOPA5GT) were initially screened according to bioinformatics and qRT-PCR analyses. Silencing HmoCYP76AD1, HmoDODAα1, HmoDODAα2 or HmocDOPA5GT resulted in loss of red pigment. HmoDODAα1 displayed a high level of L-DOPA 4,5-dioxygenase activity to produce betalamic acid and formed yellow betaxanthin. Co-expression of HmoCYP76AD1, HmoDODAα1 and HmocDOPA5GT in Nicotiana benthamiana and yeast resulted in high abundance of betalain pigments with a red color. These results suggested that HmoCYP76AD1, HmoDODAα1, and HmocDOPA5GT play key roles in betalain biosynthesis in Hylocereus. The results of the present study provide novel genes for molecular breeding programs of pitaya.

Wounding stress induces phenolic accumulation in pitaya fruit (Hylocereus undatus). This study aimed to elucidate the possible molecular mechanism underlying the wound-induced phenolic biosynthesis in fresh-cut pitaya fruit based on transcriptomic and bioinformatic analysis. Wounding stress induced the activation of metabolic pathways associated with phenolic biosynthesis, including secondary metabolism such as phenylpropanoid pathway and flavonoid pathway, signaling molecules metabolism such as ethylene, reactive oxygen species and jasmonic acid, and primary metabolism such as glycolysis, pentose phosphate pathway and shikimate pathway. Moreover, weighted gene coexpression network analysis and evolutionary relationship analysis revealed that 1 HuMYB, 3 HubHLHs, 7 HuAP2-EREBPs could be identified as putative transcription factors participating in the regulation of wound-induced phenolic biosynthesis in pitaya fruit. These findings validated previous study that wounding stress induces the conversion of hexose pool to supply essential carbon skeletons for the phenolic accumulation in fresh-cut pitaya fruit in transcriptional level and provide important and useful genetic information for further studies on the functions of transcription factors in wounding response in pitaya fruit.

This study aimed to characterize and compare pulps of two species of organic dragon fruits, Hylocereus undatus and Hylocereus polyrhizus, grown at the same edaphoclimatic conditions in terms of bioactive compounds and physicochemical aspects. No significant differences were observed between purple and white pulps concerning moisture, ascorbic acid concentration, and DPPH-assay antioxidant activity. Purple pulp demonstrated higher values for pH, Folin-Ciocalteau reducing capacity, and FRAP-assay antioxidant activity, lower acidity, and expressive total betalain content, suggesting higher bioactive potential. The main phenolic compounds identified in purple pulp were rutin, hesperidin, ferulic, and sinapic acids, while the white one was rich in chlorogenic acid. The major organic acids identified in both pulps were malic, citric, formic, pipecolic, and ascorbic. Pipecolic acid was detected in both, although more predominant in purple pulp, in remarkable concentrations, being the first report of it in the Cactaceae family. The found results indicate potential bioactivity, contributing to confirm the status of superfruit of these exotic fruits.

Aji SP, Anandito BK, Nurhartadi E. 2013. Study of addition of various types of honey as alternative sweetener in white dragon (Hylocereus undatus) juice drink. Biofarmasi 11: 13-18. Indonesia is a tropical country, so people tend to consume lots of water to refresh the body. Along with the development of technology and the desire of people to come back to healthy life, it is necessary to manufacture beverage that have functional value. Dragon fruit has a large nutritional content. Dragon fruit contains several bioactive components, such as: anthocyanin, vitamin C, beta-carotene and soluble fiber in the form of pectin. Therefore, the processing of dragon fruit into juice that contains bioactive components is potential. In general, fruit juice beverage use a sweetener based on sucrose, therefore in this study it was used honey as an alternative sweetener that has a functional value. This research aimed to study the making of white dragon juice (Hylocereus undatus) using honey sweetener types of rambutan, kelengkeng and randu, and to analyze its chemical characteristic (vitamin C and antioxidant) and sensory properties (taste, color, aftertaste, overall). In this study, it was used white dragon fruit and various types of honey such as randu honey, rambutan honey and kelengkeng honey with the concentrations of 5%, 10% and 15%, respectively. The results showed that dragon fruit juice with the addition of rambutan honey contained vitamin C and antioxidant greater than the addition of randu and kelengkeng honey. The addition of honey with the different concentrations (5%, 10%, 15%) could also increase vitamin C and antioxidant contents in the produced functional beverage. The higher concentration of honey that added, the higher produced vitamin C and antioxidant contents. Meanwhile, the sensory test results of color, taste, aftertaste and overall parameters for dragon fruit juice samples with the addition of rambutan, rambutan and kelengkeng honey, the average of panelists gave a like score. But, the higher concentration of honey that added, the sensory results indicated the panelist preference decreased. According to the results of the panelist study showed the level of fondness in all types of honey at a concentration of 10%.

The objective of this work was to obtain the drying kinetic curves of white-fleshed ‘pitaya’ peels and characterize the obtained powder regarding physical and chemical parameters. Different mathematical models were fitted to the experimental data of drying kinetics, considering the coefficient of determination (R2), mean square deviation (MSD) and residual distribution as fit criteria. The peels had an initial moisture content of 93.38% (w.b.) and final moisture contents of 5.39% at temperature of 50 °C, 5.27% at 60 °C and 4.40% at 70 °C. After drying, the peels were disintegrated to obtain the powders and characterized for moisture content, reducing sugars, total titratable acidity, ascorbic acid, betacyanins, betaxanthins, water activity and color, in order to evaluate the influence of temperature on the quality of powders. The Page model was the one that best fitted to the experimental data, presenting coefficient of determination higher than 0.998, mean square deviation lower than 0.02 and random distribution of residuals. Increment in drying air temperature promoted increase of pH, ascorbic acid, luminosity and yellowness, and reduction of moisture content, reducing sugars, acidity, betacyanins, betaxanthins, water activity and redness. Considering the retention of betalains, the drying temperature of 50 °C is the most suitable for the production and use of ‘pitaya’ peel powder. RESUMO Objetivou-se com este trabalho obter as curvas de cinética de secagem das cascas de pitaya branca e caracterizar o pó obtido quanto aos parâmetros físicos e químicos. Diferentes modelos matemáticos foram ajustados aos dados experimentais de cinética de secagem, considerando-se como critério de ajuste o coeficiente de determinação (R2), o desvio quadrático médio (DQM) e a distribuição dos resíduos. As cascas apresentaram teor de água inicial de 93,38% b.u. e final de 5,39% na temperatura de 50 °C, 5,27% em 60 °C e 4,40% em 70 °C. Após as secagens, as cascas foram desintegradas, para a obtenção dos pós e caracterizadas quanto ao teor de água, açúcares redutores, acidez total titulável, ácido ascórbico, betacianinas, betaxantinas, atividade de água e cor, com a finalidade de se avaliar a influência da temperatura na qualidade dos pós. O modelo de Page foi o que melhor se ajustou aos dados experimentais, apresentando coeficiente de determinação maior do que 0,998, desvio quadrático médio menor que 0,02 e distribuição aleatória dos resíduos. O aumento da temperatura do ar de secagem promoveu aumento do pH, ácido ascórbico, luminosidade e intensidade de amarelo e a redução do teor de água, açúcares redutores, acidez, betacianinas, betaxantinas, atividade de água e intensidade de vermelho. Considerando-se a retenção de betalaínas, a temperatura de secagem de 50 oC é a mais adequada para produção e utilização das cascas de pitaya em pó.

This study aimed to compare the effect of red dragon fruit extract (Hylocereus polyrhizus) and white dragon fruit extract (Hylocereus undatus) to total cholesterol levels in white rats (Rattus norvegicus). Total of 30 males white wistar strains were divided into five treatments i.e: (1) standard feed and Na-CMC 1% (K1), (2) standard feed and quail egg 10ml/kgBW (K2), (3) standard feed, quail egg 10ml/kgBW and simvastatin dose 0,72mg/day (P1), (4) standard feed, quail egg 10ml/kgBW and red dragon fruit extract dose 60mg/200gBW/day (P2), (3) standard feed, quail egg 10 ml/kgBW and white dragon fruit extract dose 120mg/200gBW/day (P3). The intervention was carried out for 14 days after 7 days acclimatization period. Data was analyzed by One Way ANOVA test and continued with Post Hoc Bonferroni test (p=0.05). In P2 group, there was a difference of total blood cholesterol level by 25.83 mg/dl compared with the positive control group and statistically significant (p 0.05). The comparison between red dragon extract group and white dragon extract showed a non-significant difference (p>0.05). Red dragon fruit extract and white dragon extract have a potential effect to improve hypercholesterolemia conditions.

Studies on the cacti of the genera, Hylocereus Tropical and Subtropical America are scarce. Cultivation and consumption of different species and varieties of pitaya (Hylocereus undatus) may represent a source of diversified agricultural activity since these species contain rich bioactive compounds that add a rustic beauty to the cultivation of the fruit in addition to the benefits they bring to the health of the population. The functional attributes assigned to this fruit, prompt the need to study its physical, chemical, nutritional, pharmacological and toxicological characteristics. The objective of this study was to review the literature on the pitaya, investigating the relationship between post-harvest production, technological and pharmaceutical applications, in addition to nutritional properties, and the chemical components that are beneficial and toxic to health. Hence, a literature search at the PubMed and SciELO Medicine® sites, with descriptors "Hylocereus" and "pitaya" was held. Recent studies on the bioactive compounds in pulp and peel, antioxidant activity and the relationship between use and health were mainly selected, based on in vivo studies. Based on the articles studied, observation showed that the intake of bioactive compounds present in pitaya boosts immunity in individuals, thus inducing better health and improving physical and mental performance. However, additional research is necessary to obtain consistent and reliable data to explore unrestricted use by the food, pharmaceutical and cosmetic industry. Key words: Cactaceous, pitaya, Hylocereus undatus.

This study isolated and identified the fungus that causes postharvest disease in dragon fruit (Hylocereus undatus Haw.). The in vitro and in vivo antifungal activity of some essential oils were evaluated against the fungus. Morphophysiological and molecular identification confirmed the fungus was Alternaria alternata. The essential oils of Cinnamomum zeylanicum, Cymbopogon flexuosus, Eucalyptus globulus, Eugenia caryophyllus, and Rosmarinus officinalis were evaluated by the microdilution broth technique, disc diffusion, scanning electron microscopy, and fluorescence microscopy. Evaluation of the composition of the essential oils by gas chromatography/mass spectrometry revealed substantial amounts of eugenol as a major constituent of E. caryophyllus and C. zeylanicum (90.50% and 80.70%, respectively). The other essential oils of R. officinalis contained α-pinene (24.5%) and camphor (22.0%) as major components. E. globulus contained 1,8-cineole (78.9%). C. flexuosus contained neral (35.1%) and geranial (42.6%). C. zeylanicum and E. caryophyllus were the most active against the isolated fungi at minimum inhibitory concentrations of 250 and 500 μg/ml, respectively, causing morphological changes in the hyphae. The in vivo assay indicated that the fruits that were treated with E. caryophyllus at concentrations of 500 and 1000 μg/ml exhibited a 31% reduction of mycelial growth compared with the control. These results suggest that the essential oils of C. zeylanicum and E. caryophyllus are active against A. alternata both in vitro and in vivo, which may be promising for control of the microorganism.

In this study, the efficacy of dragon fruit peel (DFP) powder as antioxidant dietary fibre (ADF), at two different concentrations (T1-1.5% and T2-3.0%), on quality improvement and susceptibility to lipid oxidation of chicken nuggets during 20 days of refrigerated storage was assessed. DFP, rich in dietary fibre (56.91%) with higher insoluble dietary fibre, phenolics (36–39 mgGAE/100 g) content and possessing good radical scavenging activity as well as reducing power, contained 10.36% protein, 4.48% fat and 2.34% ash. HPLC analysis revealed presence of high concentrations of gallic and ferulic acid, among the phenolics. Incorporation of DFP in nuggets although decreased the pH but improved emulsion stability as well as cooking yield and had higher protein, ash and lower fat content. Further, the treated nuggets had significantly (p 0.05) increase in the scores of other attributes compared to control samples. DFP significantly decreased lipid peroxidation, odour scores and microbial load in chicken nuggets during 20 days of storage period. From the study, it could be deduced that DFP rich in bioactive components had positive influence on the nutritional quality of chicken nuggets and could also be used as ADF in muscle food without affecting the quality and acceptability of products. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13197-019-04180-z) contains supplementary material, which is available to authorized users.

The AOAC 2007.1 quick, easy, cheap, effective, rugged, and safe official method, together with gas chromatography coupled to a triple quadrupole mass spectrometer was applied for the analysis of 38 multiclass pesticides from dried fruits typically cultivated and exported from Colombia: uchuva (Physalis peruviana), lulo (Solanum quitoense), guanabana (Anona muricata), and pitahaya (Hylocereus undatus). The whole method was validated in terms of matrix-matched calibration, matrix effect, and recovery using atrazine-d5 as internal standard, triphenylphosphate for quality control of the injection, and a proper mixture of analytes protectants. Matrix-matched calibration data were found satisfactory for all pesticides and dried fruits, reporting R2 values above 0.99. Matrix effect values evidenced the existence of such effect in most cases. The applied procedure gave satisfactory recovery percentages (70-120%) and relative standard deviation values (< 20%) for 92% of the 456 combinations pesticide/fruit studied (spiked levels of 25, 200, and 400 µg/kg). Finally, 20 real dried fruit samples were analyzed and residues of tebuconazole were found in two samples of uchuva at a concentration below the lowest calibration level of the method for one of them and at 10.8 ± 1.6 µg/kg for the other, being below or similar to the general maximum residue level established for monitoring purposes in food applications.

Many foods from Indonesia are cooked through the frying process using cooking oil. Good cooking oil is oil that has a low amount of peroxide and acid. The purpose of this study was to find the effect of adding dragon fruit juice (Hylocereus undatus)to peroxide numbers and acid numbers in used cooking oil. Peroxide numbers were measured using the iodometry method, whereas acidic numbers were carried out by the acid-base method. The results of this study indicated that after the addition of dragon fruit juice the peroxide number was dropped to 2.4 meg / kg, whereas in acid numbers an acid number was increased to 6.08 percent.

A pitaia é uma frutífera tropical, pertencente à família Cactaceae, com elevado potencial produtivo, nutritivo, econômico e social para a agricultura familiar, sendo uma cultura ainda pouco conhecida e com escassas informações sobre as condições que afetam a germinação das diferentes espécies de pitaia. Assim, o trabalho teve como objetivo avaliar a influência da temperatura e da luminosidade na germinação de sementes de três genótipos de pitaia. Para avaliar o efeito da temperatura na qualidade fisiológica das sementes foram utilizadas as espécies Selenicereus setaceus (pitaia-do-cerrado), Hylocereus undatus (casca vermelha e polpa branca) e Hylocereus polyrhizus (casca vermelha rosada e polpa vermelha) submetidas à germinação em sete temperaturas (15 °C, 20 °C, 25 °C, 30 °C e 35 °C, e em temperaturas alternadas: 15-25 ºC e 20-30 ºC, todas com fotoperíodo de 12 horas). As avaliações realizadas foram: porcentagem de germinação, índice de velocidade de germinação e tempo para ocorrência de 50% de germinação. Para a avaliação da influência da luminosidade, as sementes foram acondicionadas em frasco envolto por papel alumínio, a fim de proteger as sementes de qualquer contato com luminosidade, e armazenadas em refrigerador em temperatura de 10 ± 2 °C por 365 dias. Após, foram submetidas ao tratamento com e sem luz e mantidas em BOD por 11 dias, quando se realizou a contagem das plântulas normais. As temperaturas para o máximo desempenho fisiológico das sementes das três espécies de pitaia foram de 25 °C e 20-30 ºC. Por outro lado, a temperatura mais desfavorável foi de 35 °C. A espécie Selenicereus setaceus apresentou maior percentual de germinação e vigor em todas as temperaturas avaliadas. As espécies avaliadas demonstraram ser fotoblásticas positivas.

Submitted by Leticia Schettini (leticia@ufrrj.br) on 2022-02-01T19:02:20Z No. of bitstreams: 1 2019 - Ivanildo de Souza Corte.pdf: 1393810 bytes, checksum: 8dcb98d6eb25fda78442d35e17fb2b4f (MD5) Made available in DSpace on 2022-02-01T19:02:20Z (GMT). No. of bitstreams: 1 2019 - Ivanildo de Souza Corte.pdf: 1393810 bytes, checksum: 8dcb98d6eb25fda78442d35e17fb2b4f (MD5) Previous issue date: 2019-05-23 CAPES - Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior The objective of this study was to evaluate the growth of species of pitahaya in a typical semi arid climate, under the following conditions: (1) sub-forest of native vegetation; (2) on shade cover with 50% sunlight interception and (3) in full sunshine regime. The experimental design was a randomized block design with four treatments, that is, different species of pitahies: (1) (Hylocereus costaricensis), (2) pitaya-red-pulp-white (Hylocereus undatus), (3) pitaya-native of the Cerrado (Selenicereus setaceus) and (4) (Selenicereus spp), with four replicates or blocks, four useful plants per plot. For the planting of the cuttings pits were prepared in the dimensions of 0.40 X 0.40 X 0.40 m, spacing 2.5 m between rows and 2 m between plants on the same row. The growth of each plant was managed, leaving only two shoots followed and the length of these shoots was monitored along one year of cultivation, as well as the total height relative to the soil. The data were submitted to analysis of variance using the Rbio program. The results made it possible to conclude that in the sub-forest environment of native vegetation, the highest survival rate of the implanted cuttings occurs for Selenicereus setaceus and the lowest for Hylocereus costaricensis; and also, the four species of pitahies in this environment, have, after 12 months of cultivation, similar vegetative growth. In the environment with sombrite cover, for the four species tested, close to 100% of the implanted cuttings grow and the species Hylocereus costaricensis has the highest vegetative growth performance. In full sunshine regime there is a great mortality of the pitahages, not allowing to make better analyzes of their behavior; still in this situation, the native species of the Cerrado shows greater tolerance, whereas Hylocereus costaricensis is the most sensitive. Thus, shading increases the percentage of survival and favors the initial growth of the pitahages cultivated under the Brazilian semi-arid conditions. Objetivou-se com esse trabalho, avaliar em clima caracter?stico do semi?rido, o crescimento de esp?cies de pitaieiras, nas seguintes condi??es: (1) sub-bosque da vegeta??o nativa; (2) sob cobertura de sombrite com 50% de intercepta??o da luz solar e (3) em regime de insola??o plena. O delineamento adotado foi em blocos ao acaso, com quatro tratamentos, ou seja, diferentes esp?cies de pitaieiras: (1) pitaia-vermelha-de-polpa-vermelha (Hylocereus costaricensis), (2) pitaia-vermelha-de-polpa-branca (Hylocereus undatus), (3) pitaia-nativa do Cerrado (Selenicereus setaceus) e (4) esp?cie nativa (Selenicereus spp), com quatro repeti??es ou blocos, sendo quatro plantas ?teis por parcela. Para o plantio das estacas foram preparadas covas nas dimens?es de 0,40 X 0,40 X 0,40 m, com espa?amento de 2,5m entre linhas e 2m entre plantas na mesma linha. Manejou-se o crescimento de cada planta, deixando seguir apenas dois brotos e acompanhou-se o comprimento destes brotos ao longo de um ano de cultivo, bem como da altura total relativa ao solo. Os dados foram submetidos ? an?lise de vari?ncia utilizando-se o programa Rbio. Os resultados possibilitaram concluir que no ambiente em Sub-bosque da vegeta??o nativa, a maior taxa de sobreviv?ncia das estacas implantadas se d? para a esp?cie Selenicereus setaceus e a menor para a Hylocereus costaricensis; e ainda, as quatro esp?cies de pitaieiras, neste ambiente, t?m, depois de 12 meses de cultivo, crescimento vegetativo similares. No ambiente com cobertura de sombrite, para as quatro esp?cies testadas, pr?ximo de 100% das estacas implantadas crescem e a esp?cie Hylocereus costaricensis tem o maior desempenho em crescimento vegetativo. Em regime de insola??o plena ocorre grande mortalidade das pitaieiras, n?o permitindo fazer melhores an?lises do seu comportamento; ainda nesta situa??o, a esp?cie nativa do Cerrado demonstra maior toler?ncia, enquando a Hylocereus costaricensis ? a mais sens?vel. Assim, o sombreamento aumenta o percentual de sobreviv?ncia e favorece o crescimento inicial das pitaieiras cultivadas nas condi??es do semi?rido brasileiro.

Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2019-04-25T11:53:48Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Patrícia Graosque ulguim Zuge cd.pdf: 1666489 bytes, checksum: d5c28031087cba0c62ffa677408efe00 (MD5) Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2019-04-29T20:18:07Z (GMT) No. of bitstreams: 2 Patrícia Graosque ulguim Zuge cd.pdf: 1666489 bytes, checksum: d5c28031087cba0c62ffa677408efe00 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Made available in DSpace on 2019-04-29T20:18:07Z (GMT). No. of bitstreams: 2 Patrícia Graosque ulguim Zuge cd.pdf: 1666489 bytes, checksum: d5c28031087cba0c62ffa677408efe00 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2019-03-25 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES Objetivou-se com este estudo, desenvolver protocolos de produção de mudas de pitaya por meio da micropropagação. Primeiramente foram realizados cinco experimentos, o objetivo foi gerar um protocolo de produção de mudas de Hylocereus undatus e Hylocereus polyrhizus, com as etapas de estabelecimento, multiplicação, enraizamento e aclimatização. No segundo trabalho, objetivou-se avaliar as porções do cladódio e 6-benzilaminopurina na multiplicação de Hylocereus undatus. Os trabalhos foram desenvolvidos no Laboratório de Propagação de Plantas Frutíferas da Universidade Federal de Pelotas. Cladódios foram segmentados e enraizados em floreiras, as brotações foram utilizados para o estabelecimento. O meio de cultura em todas as etapas foi o MS (Murashige & Skoog) e o pH ajustado em 5,8. No estabelecimento, o experimento foi em esquema fatorial 2x5 (dois genótipos e doses de 6-benzilaminopurina (0, 1, 2, 3 e 4mg L-1)), com uma aréola por explante. Após 90 dias, foram avaliados o número de brotações e a porcentagem de explantes regenerados. Na multiplicação foram dois experimentos; o primeiro conduzido em esquema fatorial 2x5(genótipos e doses de Zeatina (0, 0,2, 0,4, 0,6 e 0,8mg L-1) e após 60 dias foram avaliados: número e comprimento de brotações, taxa de multiplicação, número e comprimento de raízes e massa de matéria seca total. No segundo estudo, foi esquema fatorial 2x4 (dois genótipos e doses de 6-benzilaminopurina (0, 0,3, 0,6 e 0,9mg L-1)), após 60 dias foram avaliados: número de brotações e taxa de multiplicação. Na etapa de enraizamento foram testadas doses de ácido indolbutírico (0, 0,2, 0,4 e 0,6mg L-1) em Hylocereus undatus, após 60 dias foram avaliados: número e comprimento de raízes e número e comprimento de brotações. Para aclimatização, foram testados, dois genótipos e os substratos casca de arroz carbonizada, vermiculita, fibra de coco e turfa® fértil. O experimento foi conduzido em casa de vegetação com temperatura controlada, 25°C ± 2°C. Após 60 dias foram avaliadas o comprimento de parte aérea, número de aréolas, número de raízes primárias e secundárias, comprimento de raiz e massa de matéria seca de raiz e parte aérea. Em outro experimento, foi testada a influência das porções do cladódio (apical, mediana e basal) e doses de 6-benzilaminopurina (0, 1, 2, 3 e 4mg L-1) na multiplicação de Hylocereus undatus. No estabelecimento a dose de 2mg L-1 de 6-benzilminopurina para Hylocereus polyrhizus e 4mg L-1 para Hylocereus undatus promovem a indução de brotações e número de brotos. Não é necessário o uso de ácido indolbutírico no enraizamento de Hylocereus undatus. A Zeatina apresentou efeito negativo na multiplicação, com 6-benzilminopurina o maior número de brotos e taxa de multiplicação ocorreu entre as doses 0,6 e 0,9mg L-1. Para a aclimatização a casca de arroz carbonizada e vermiculita favoreceram o desenvolvimento das raízes dos dois genótipos. As porções mediana e basal apresentam maior número de brotações e a dose 2mg L-1de 6-benzilminopurina são indicadas para multiplicação de Hylocereus undatus. The objective of this study was to develop protocols for the production of pitaya seedlings through micropropagation. First, five experiments were carried out. The objective was to generate a protocol for seedling production of Hylocereus undatus and Hylocereus polyrhizus, with the establishment, multiplication, rooting and acclimatization stages. In the second work, we aimed to evaluate the cladode and 6-benzylaminopurine portions in Hylocereus undatus multiplication. The works were developed in the Laboratory of Propagation of Fruit Plants of the Federal University of Pelotas. Cladodes were segmented and rooted in flowerbeds, the shoots were used for the establishment. The culture medium at all stages was MS (Murashige & Skoog) and pH adjusted to 5.8. At the establishment, the experiment was in a 2x5 factorial scheme (two genotypes and doses of 6-benzylaminopurine (0, 1, 2, 3 and 4mg L-1)), with one areola per explant. After 90 days, the number of shoots and the percentage of regenerated explants were evaluated. In the multiplication were two experiments; the first one was conducted in a 2x5 factorial scheme (genotypes and doses of Zeatin (0, 0.2, 0.4, 0.6 and 0.8mg L-1) and after 60 days were evaluated: number and length of shoots, multiplication rate, number and length of roots and mass of total dry matter. In the second study, a 2x4 factorial scheme (two genotypes and doses of 6-benzylaminopurine (0, 0.3, 0.6 and 0.9mg L-1), after 60 days were evaluated: number of shoots and multiplication rate. In the rooting stage, doses of indolebutyric acid (0, 0.2, 0.4 and 0.6mg L-1) were tested in Hylocereus undatus, after 60 days were evaluated: number and length of roots and number and length of shoots. For acclimatization, two genotypes and the substrates were bark of charred rice, vermiculite, coconut fiber and peat ® Fertil. The experiment was conducted in a greenhouse with controlled temperature, 25 °C ± 2 °C. After 60 days, shoot length, number of areolas, number of primary and secondary roots, root length and dry mass of root and shoot were evaluated. In another experiment, the influence of the cladode portions (apical, median and basal) and doses of 6-benzylaminopurine (0, 1, 2, 3 and 4mg L-1) on the multiplication of Hylocereus undatus were tested. In the establishment the dose of 2mg L-1 of 6-benzylminopurine to Hylocereus polyrhizus and 4mg L-1 to Hylocereus undatus promoted the induction of shoots and number of shoots. It is not necessary to use indolebutyric acid in the rooting of Hylocereus undatus. Zeatin presented a negative effect on multiplication, with 6-benzylminopurine the highest number of shoots and multiplication rate occurred between doses 0.6 and 0.9mg L-1. For the acclimatization the bark of charred rice and vermiculite favored the development of the roots of the two genotypes. The median and basal portions present a higher number of shoots and the dose 2mg L-1 of 6-benzylminopurine are indicated for multiplication of Hylocereus undatus.

No Algarve, onde existem condições edafoclimáticas favoráveis ao cultivo de algumas espécies frutícolas exóticas, oriundas de climas tropicais ou subtropicais, surge o interesse no cultivo da pitaia. Esta cultura apresenta altas produções em alguns países e é adequada para terrenos de pequenas dimensões. Ela acaba por satisfazer também a necessidade de diversificar a fruticultura da região. Devido à sua aparência exótica e ao seu alto valor nutritivo, a pitaia tem sido cada vez mais procurada em diversos países, principalmente pelos mercados asiáticos e europeus. Para desenvolver a cultura da pitaia no Algarve foi constituído um grupo operacional cujo objetivo principal visa inovar ao nível das tecnologias de produção para a pitaia vermelha, testando a sua produtividade, rusticidade e qualidade dos frutos. Começou-se por fazer um levantamento da situação desta cultura em Portugal. Estão também a ser instalados vários campos de ensaio/recolha de dados, sobre várias espécies de pitaia vermelha. PDR2020-101-031201 info:eu-repo/semantics/publishedVersion

Night-blooming cereus (Hylocereus undatus A. Berger) is generally used as rootstock of ornamental cactus because of its rapid growth and tolerance to humid substrates. Since 2002, in Gran Buenos Aires, a new disease has been observed in grafted crops in all production stages. Incidence was as much as 30% in many greenhouses. Symptoms consisted of soft rot that started near the soil line and developed upward until it affected all the rootstock. The scion was not rotten, but died as a consequence of rootstock infection. All the roots were symptomless. For pathogen isolation, symptomatic tissues were surface disinfected by a 1-min immersion in 0.2% NaOCl, placed on potato dextrose agar (PDA), and incubated at 22 ± 2°C. Only a Fusarium spp. was consistently isolated in pure culture. Twenty healthy potted night-blooming cereus plants, 10 of them previously injured with needles on the rootstock near the soil line, were gently removed from the substrate and inoculated by a 1-min immersion of their base in a suspension of 1.4 × 106 conidia per ml of sterile distilled water, prepared from 15-day-old cultures. Ten control plants, five of them previously injured, were immersed in sterile distilled water. Inoculated and noninoculated plants were replanted in the original substrate, placed in a climatic chamber at 22 ± 2°C, and monitored for disease expression. Basal rot was observed on all injured inoculated plants 12 days after inoculation. Symptoms on undamaged plants appeared 22 days after inoculation. After 72 days of incubation, all inoculated plants were totally rotten. Control plants remained symptomless. The same pathogen was reisolated to fulfill Koch's postulates. For species identification, single-spore cultures were grown on PDA and carnation leaf agar in a climatic chamber at 23 ± 2°C with a 12-h darkness/near ultraviolet light regimen. The micromorphology and culture features, mainly conidial ontogeny, were consistent with descriptions of Fusarium oxysporum Schlechtend.:Fr. (1). The pathogen was able to penetrate undamaged tissues. Needle injuries accelerated infection. To our knowledge, this is the first report of Fusarium oxysporum on H. undatus in Gran Buenos Aires, Argentina. A culture of the pathogen was deposited at the fungal collection of PRHIDEB-CONICET (University of Buenos Aires) as BAFCult 3158. Reference: (1) P. E. Nelson et al. Fusarium species. An Illustrated Manual for Identification. The Pennsylvania State University Press, University Park, PA, 1983.

Pitahaya (Hylocereus undatus (Haw.) Britton & Rose), a cactus grown for its edible fruit, is gaining popularity in South Florida as part of the specialty tropical fruit market. In July 2009, flowers and fruit were discovered with an uncharacterized rot. Small, circular, light brown, depressed lesions expanded to form large areas of rot on flowers and fruit in 7 to 10 days. The lesions produced large amounts of dark fungal spores. Single-spore isolates were identified morphologically and by aligning internal transcribed spacer (ITS) and glyceraldehyde-3-phosphate dehydrogenase (gpd) DNA sequences from the isolates with previously published sequences of Bipolaris, Drechslera, and Cochliobolus species. Conidia from the dark, blackish brown colonies were formed at the tips of pale golden brown, straight to flexuous conidiophores, 99 (184) 313 × 3 (6) 8 μm and slightly swollen at the apex and base. Conidia were pale-to-medium golden brown, smooth and clavate with a protuberant hilum, 24 (40) 51 × 9 (10) 13 μm, and two to four distoseptate. The isolates closely match descriptions of Bipolaris cactivora (= Drechslera cactivora) (3,4), although isolates from pitahaya had smaller conidia (30 to 65 μm) than previously reported. Conidial characteristics from a B. cactivora herbarium specimen BPI 431621 (U.S. National Fungus Collections) closely matched (29 (36) 50 × 8 (9) 11 μm, two to four distoseptate) our isolates. ITS (GenBank Accession Nox. HM598677–79) sequences aligned most closely (99.7% homology) with another B. cactivora isolate from China (GU390882), and both ITS and gpd (GenBank Accession Nos. HM598680–82) sequences indicate a close relationship to Bipolaris indica. Wounded or nonwounded mature pitahaya fruit and mature stems were inoculated with either a mycelia plug or a 15-μl 0.3% agar drop containing 105 conidia ml–1. Lesion diameters were measured after 7 days at 25°C, the fungus was reisolated on potato dextrose agar (PDA) and its identity was confirmed. Mean lesion diameters on mature fruit were 6.0 to 10.8 mm, depending on the inoculation method, and sporulation began 6 days after inoculation. On mature plant stems, wound-inoculated treatments formed 1.8 to 3.4 mm lesions, but nonwounded inoculations and controls were negative. Lesions were light tan, circular, and did not sporulate. To our knowledge, this is the first report of fruit rot caused by B. cactivora on pitahaya in Florida. The same pathogen causes stem rot of the Cactaceae in Europe and the United States (2) and a fruit rot on pitahaya in Japan (4). In Florida, it has been reported as causing a leaf spot on Portulaca oleracea (1). Our results indicate that B. cactivora causes flower and fruit rot on pitahaya, but does not seriously affect mature plant stems. The flower rot does not appear to significantly increase incidence but may provide inoculum for the fruit rot. The high incidence of fruit rot affecting commercial operations in Miami-Dade County over the past 2 years requires an effective disease management strategy. References: (1) S. A. Alfieri, Jr. et al. Bull. 14. Index of Plant Diseases in Florida (Revised). Florida Dep. Agric. Consumer Serv., Div. Plant Ind., 1984. (2) R. D. Durbin et al. Phytopathology 45:509, 1955. (3) M. B. Ellis. Page 432 in: Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew, England. 1971. (4) S. Taba et al. J. Gen. Plant Pathol. 73:374, 2007.