Aline Rocha

Genetic Diversity of 'Uba ´' Mango Tree Using ISSR Markers

In this study, the genetic diversity of ‘Ubá’ mango trees cultivated at the Zona da Mata of Minas Gerais State, Brazil, was assessed, to identify whether there is variability in the plants grown in the region, justifying the mass selection as a breeding method. We used 102 accessions. Leaves were collected for extraction of genomic DNA, which was amplified with nine ISSR primers. The data obtained by the analysis of electrophoretic patterns were arranged in a binary matrix, considering 0 for the absence and 1 for the presence of bands. Based on these data, we performed the analysis of genetic dissimilarity and carried out the cluster analysis by the methods of Tocher and graphical dispersion. The most similar accessions are 144 and 150, both coming from Ubá, while the most divergent ones are 29 and 97, from Visconde do Rio Branco. The grouping by the Tocher method separated the accessions into six groups, 94.1% of which were allocated in the first group and showed that there is no separation of accessions depending on the sampling sites. The 3D scatter plot reinforces this conclusion. There is genetic variability among the accessions of ‘Ubá’ mango tree evaluated. Therefore, it is possible to make mass selection in open-pollinated populations.

Diversidade genética entre cultivares de mangueiras, baseada em caracteres de qualidade dos frutos

Genetic diversity among cultivars of mango based on fruit quality traits The mango crop is one of the most significant agribusiness in Brazil. Although there are many cultivars, cultivation has been done primarily with ‘Tommy Atkins’ and there are few studies on characterization and analysis of genetic diversity in different areas of production. Therefore, the objective of this work was to study the genetic diversity of fifteen mango cultivars, eight from Brazil and seven from Florida (USA), produced in the Zona da Mata Mineira region. Fifteen ripe fruits from each cultivar were collected and analyzed chemically and physically . The cultivars that showed more similarities were ‘Kent’ and ‘Palmer’. ‘Extrema’ was not grouped with the others by the UPGMA clustering method. This analysis was also used for the separation of Brazilian and USA cultivars. The principal component analysis of the chemical characteristics did not group the cultivars ‘Extrema’ and ‘Tommy Atkins’ with the others. The physical characteristics showed the same separation obtained by the UPGMA method, except for the cultivar ‘Extrema’ that was grouped with other cultivars. There was correlation between the color of the pulp, hue angle, and total soluble sugar content and between the color of the peel, b* index and percentage of peel and pulp.

Use of biofilm in the postharvest conservation of 'Pedro Sato' guava

This present work aimed to assess the effect of different concentrations of cassava starch, associated or not with prochloraz fungicide, on the postharvest conservation of ‘Pedro Sato’ guavas. Physiologically mature fruits were immersed in a solution of prochloraz (49.5 g/100 liters of water) for 5 min. Fruit treated with distilled water and air dried were used as control. They were immersed in cassava starch suspension at concentrations of 0, 20, 30 and 40 g/L, plus 0.5 mL/L of mineral oil. The fruits were stored at 21.0  1.0 °C and relative humidity of 85  5%, for 12 days, and were examined at every three days. The combination of prochloraz and cassava starch resulted in delayed loss of firmness and yellowness and inhibited the incidence of lesions caused by Colletotrichum gloeosporioides during the 12 days of storage. Fruits treated with 40 g/L of starch, whether containing prochloraz or not, had unpleasant taste and odor, which suggests the occurrence of fermentation. Control fruits, with and without prochloraz, and those treated with starch with no prochloraz, had nearly 100% lesion occurrence within the 12 days. Starch suspension of 30 g/L, containing prochloraz, was the most effective in maintaining fruit quality.

Identification of 'Ubá' mango tree zygotic and nucellar seedlings using ISSR markers

The objective of this work was to evaluate selective mating using the distribution of extreme values, among other mating strategies, on its ability to optimize the phenotypic increment of the characteristic under marker-assisted selection. The multivariate analysis was used to compare the mating strategies, using the Tochers method. The genetic simulation system (Genesys) was used to simulate three genomes (each one with a single characteristic distinguished by the heritability) and the base and initial populations. Each initial population was subjected to marker-assisted selection for 20 consecutive generations. The evaluation of the strategies was based on the estimates of the phenotypic value, in different family sizes, for the three characteristics. In all scenarios, when combining heritability and family sizes, the selective mating was superior to the others in the ability to maximize the phenotypic value. The Tochers method made it possible to differentiate the selective mating from the other strategies through the formation of specific groups consisting of matings that followed the distribution of extreme values. The multivariate analysis confirmed optimum phenotypic increments for the selective mating, for quantitative traits with heritabilities of 0.10; 0.40 and 0.70.

Identificação de plântulas zigóticas e nucelares oriundas de sementes de mangueira 'Ubá' por meio de marcadores ISSR

The objective of this work was to evaluate selective mating using the distribution of extreme values, among other mating strategies, on its ability to optimize the phenotypic increment of the characteristic under marker-assisted selection. The multivariate analysis was used to compare the mating strategies, using the Tochers method. The genetic simulation system (Genesys) was used to simulate three genomes (each one with a single characteristic distinguished by the heritability) and the base and initial populations. Each initial population was subjected to marker-assisted selection for 20 consecutive generations. The evaluation of the strategies was based on the estimates of the phenotypic value, in different family sizes, for the three characteristics. In all scenarios, when combining heritability and family sizes, the selective mating was superior to the others in the ability to maximize the phenotypic value. The Tochers method made it possible to differentiate the selective mating from the other strategies through the formation of specific groups consisting of matings that followed the distribution of extreme values. The multivariate analysis confirmed optimum phenotypic increments for the selective mating, for quantitative traits with heritabilities of 0.10; 0.40 and 0.70.

Manga 'Ubá' tratada com ethephon na pré-colheita

The ‘Uba’ mango generally ripens from November to January , and ripening in the same plant is uneven, requiringselective harvest, which may extend up to a month. We evaluated the effects of different concentrations of ethephonin promoting early uniform ripening and quality attributes of ‘Uba’ mango. In the 17