Uncovering the molecular mechanisms of russet skin formation in Niagara grapevine (Vitis vinifera × Vitis labrusca).

Grape breeding programs are mostly focused on developing new varieties with high production volume, sugar contents, and phenolic compound diversity combined with resistance and tolerance to the main pathogens under culture and adverse environmental conditions. The 'Niagara' variety (Vitis labrusca × Vitis vinifera) is one of the most widely produced and commercialized table grapes in Brazil. In this work, we selected three Niagara somatic variants with contrasting berry phenotypes and performed morphological and transcriptomic analyses of their berries. Histological sections of the berries were also performed to understand anatomical and chemical composition differences of the berry skin between the genotypes. An RNA-Seq pipeline was implemented, followed by global coexpression network modeling. 'Niagara Steck', an intensified russet mutant with the most extreme phenotype, showed the largest difference in expression and showed selection of coexpressed network modules involved in the development of its russet-like characteristics. Enrichment analysis of differently expressed genes and hub network modules revealed differences in transcription regulation, auxin signaling and cell wall and plasmatic membrane biogenesis. Cutin- and suberin-related genes were also differently expressed, supporting the anatomical differences observed with microscopy.

Phytochemical profile of Brazilian grapes (Vitis labrusca and hybrids) grown on different rootstocks.

Important factors may influence the bioactive compounds in grapes, including scion-rootstock interaction. Therefore, the bioactive compounds and antioxidant activity in grape skin and pulp fractions of 'Isabel Precoce', 'BRS Carmem', 'BRS Cora', 'BRS Violeta' and 'IAC 138-22 Máximo' were assessed. These cultivars, from genetic improvement programs in Brazil, have good adaptation to subtropical and tropical climate conditions, and can be widely used by winegrowers aiming at adding value to the grape. All grapevines were grafted onto 'IAC 766' and 'IAC 572' rootstocks under tropical conditions in Brazil. The highest concentration of bioactive compounds was found in skins of 'BRS Violeta', followed by 'IAC 138-22 Máximo', both grafted onto 'IAC 766'. There was a strong correlation between phenolic content and antioxidant properties, since antioxidant activity also decreased in the sequence: 'BRS Violeta' > 'IAC 138-22 Máximo' > 'BRS Cora' > 'BRS Carmem' > 'Isabel Precoce'. Skin from hybrid grapes ('BRS Violeta', 'IAC 138-22 Máximo', 'BRS Cora' and 'BRS Carmem') grafted in both rootstocks contains higher levels of (poly)phenolic compounds and antioxidant activity than 'Isabel Precoce' (V. labrusca). Skin from 'BRS Violeta' grafted onto 'IAC 766' stand out from the others due to their high content of bioactive compounds.

Production, physicochemical quality and antioxidant capacity of 'Niagara Rosada' grape grafted on different rootstocks / Produção, qualidade físico-química e capacidade antioxidante da uva 'Niagara Rosada' sobre diferentes porta-enxertos

The objective of this study is to evaluate the effect of rootstocks on grape production, quality and antioxidant capacity of 'Niagara Rosada' grape in two productive cycles. The work was developed in Jundiaí-SP, Brazil (26° 06' S, 46° 55' W and an average altitude of 745 m). The experimental design was in randomized blocks with subdivided plots, the plots being represented by the rootstocks and the subplots by the production cycles, with four replications, each consisting of 6 plants. The treatments consisted of a combination of 'IAC 313 Tropical', 'IAC 572 Jales', 'IAC 571-6 Jundiaí', 'IAC 766 Campinas' and '106-8 Mgt' as rootstocks and 'Niagara Rosada' as graft, and the production cycles were 2013 and 2014. The number of bunches, production and productivity of the vines, the physical characteristics of bunches, berries and stalks and the physicochemical composition of the must (soluble solids content, titratable acidity, pH and the relation soluble solids/titratable acidity) were evaluated in production cycles of 2013 and 2014). The content of chlorophylls, anthocyanins, carotenoids, flavonoids and total phenolic compounds and the antioxidant activity of grapes were also evaluated in grape berries. The rootstocks did not influence the production and physical quality of 'Niagara Rosada' grapes. As for the chemical characteristics, rootstocks only had an effect on solids content, and 'IAC 766' and '106-8 Mgt' rootstocks promoted higher values of this characteristic. Likewise, the total phenolic compounds and the antioxidant activity of the grapes were not influenced by the studied rootstocks. The vines in 2013 presented higher production and better physical characteristics of the grapes, however, the soluble solids content in this cycle was lower than in 2014.

Objetivou-se avaliar a influência de porta-enxertos na produção da videira, na qualidade e capacidade antioxidante da uva 'Niagara Rosada' em dois ciclos produtivos. O trabalho foi realizado em Jundiaí-SP, Brasil (26° 06' S, 46° 55' W e uma altitude média de 745m). O delineamento experimental foi de blocos causalizados em parcelas subdivididas, as parcelas foram representas pelos porta-enxertos e as subparcelas pelos ciclos de produção, com quatro repetições, constituídas de 6 plantas. Os tratamentos consistiram na combinação entre os porta-enxertos 'IAC 313 Tropical', 'IAC 572 Jales', 'IAC 571-6 Jundiaí', 'IAC 766 Campinas' e '106-8 Mgt' e a variedade copa 'Niagara Rosada', e os ciclos produtivos de 2013 e 2014. O número de cachos, produção e produtividade das videiras, as características físicas de cachos, bagas e engaços e a composição físico-química do mosto (teor de sólidos solúveis, acidez titulável, pH e relação sólidos solúveis/acidez titulável) foram avaliados nos ciclos de produção de 2013 e 2014. Avaliou-se ainda nas bagas das uvas o conteúdo de clorofilas, antocianinas, carotenoides, flavonoides e compostos fenólicos totais e a atividade antioxidante. Os porta-enxertos não influenciaram a produção e a qualidade física da uva 'Niagara Rosada'. Quanto as características químicas houve efeito dos porta-enxertos apenas no teor de sólidos solúveis, sendo que os porta-enxertos 'IAC 766' e '106-8 Mgt' promoveram maiores valores dessa característica. Da mesma forma, os compostos fenólicos totais e a atividade antioxidante das uvas não foram influenciados pelos porta-enxertos estudados. As videiras, em 2013 apresentaram maior produção e melhores características físicas das uvas, no entanto, o teor de sólidos solúveis nesse ciclo foi inferior ao de 2014.

Genetic structure and molecular diversity of Brazilian grapevine germplasm: Management and use in breeding programs.

The management of germplasm banks is complex, especially when many accessions are involved. Microsatellite markers are an efficient tool for assessing the genetic diversity of germplasm collections, optimizing their use in breeding programs. This study genetically characterizes a large collection of 410 grapevine accessions maintained at the Agronomic Institute of Campinas (IAC) (Brazil). The accessions were genotyped with 17 highly polymorphic microsatellite markers. Genetic data were analyzed to determine the genetic structure of the germplasm, quantify its allelic diversity, suggest the composition of a core collection, and discover cases of synonymy, duplication, and misnaming. A total of 304 alleles were obtained, and 334 unique genotypes were identified. The molecular profiles of 145 accessions were confirmed according to the literature and databases, and the molecular profiles of more than 100 genotypes were reported for the first time. The analysis of the genetic structure revealed different levels of stratification. The primary division was between accessions related to Vitis vinifera and V. labrusca, followed by their separation from wild grapevine. A core collection of 120 genotypes captured 100% of all detected alleles. The accessions selected for the core collection may be used in future phenotyping efforts, in genome association studies, and for conservation purposes. Genetic divergence among accessions has practical applications in grape breeding programs, as the choice of relatively divergent parents will maximize the frequency of progeny with superior characteristics. Together, our results can enhance the management of grapevine germplasm and guide the efficient exploitation of genetic diversity to facilitate the development of new grape cultivars for fresh fruits, wine, and rootstock.

Grape juices produced from new hybrid varieties grown on Brazilian rootstocks - Bioactive compounds, organic acids and antioxidant capacity.

The objective of this study was to assess the content of bioactive compounds, organic acids and antioxidant capacity of grape juices from Isabel Precoce, BRS Carmem, BRS Cora and IAC 138-22 Máximo varieties grown on the 'IAC 766' and 'IAC 572' rootstocks under tropical conditions in Brazil. In general, the color attributes of the 'Isabel Precoce' juice were inferior to those of the other juices due to their low anthocyanin content. In contrast, 'IAC 138-22 Máximo' juices showed the highest content of most individual anthocyanins, flavonols, trans-resveratrol and total phenolic compounds, and thus, higher antioxidant capacity. Except for 'BRS Carmem', all the juices presented higher sugar accumulation when 'IAC 766' was used. This rootstock also contributed to the accumulation of t-resveratrol and most of individual anthocyanins in the 'IAC 138-22 Máximo' juices. However, the monomeric anthocyanin content was higher in 'BRS Carmem' juices when 'IAC 572' rootstock was used.

Genetic structure of mangaba (Hancornia speciosa Gomes) populations in the cerrado region of central Brazil / Estrutura genética de subpopulações de mangabeira (Hancornia speciosa Gomes) no cerrado do Brasil central

Mangaba tree (Hancornia speciosa Gomes) is a fruit species with great potential for commercial exploitation, found in most regions of Brazil and highly frequent in the Cerrado biome. Information on the genetic variability in this biome is scarce. This study aimed at characterizing the genetic structure of eight populations found in the states of Goiás, Bahia and Minas Gerais by using RAPD markers. Genetic variability was assessed by the analysis of variance on molecular data. A significant proportion of genetic variance was found among populations, corresponding to 19.6 % of the total variation. The correlation between the matrices of geographic and genetic distances was not significant, indicating that there is no spatial structure of the genetic variability among the populations, for the RAPD marker loci used here. The high variability suggests that a strategy for in situ, as well as ex situ conservation, must be based on sampling a large number of local populations.

A mangabeira (Hancornia speciosa Gomes) é uma espécie frutífera com grande potencial para exploração econômica, encontrada em várias regiões do Brasil, sendo freqüente no bioma Cerrado. Informações sobre a variabilidade genética das populações existentes neste bioma são escassas. Este estudo teve como objetivo caracterizar a estrutura genética de oito populações situadas nos Estados de Goiás, Bahia e Minas Gerais por meio de marcadores RAPD. A estrutura da variabilidade genética foi avaliada utilizando-se a análise de variância de dados moleculares. Uma proporção significativa da variância genética foi encontrada entre populações, correspondendo a 19,6 % da variação total. A correlação entre as matrizes de distâncias geográficas e genéticas não foi significativa, indicando que não existe estruturação espacial da variabilidade genética entre populações, para os locos marcadores RAPD utilizados. A alta variabilidade sugere que estratégias para conservação in situ, bem como ex situ, devem ser baseadas em amostragem de um grande número de populações locais.

Garlic extract improves budbreak of the 'Niagara Rosada' grapevines on sub-tropical regions / Extrato de alho melhora a superação da dormência de videiras 'Niagara Rosada' em regiões subtropicais

In the regions with mild winters, usually the chilling requirements for bud dormancy release of grapevines are not fulfilled, and only the highly toxic products CaCN2 (calcium cyanamide) and H2CN2 (hydrogen cyanamide) are recommended in conventional viticulture for budbreak. The purpose of this study was to verify the effect of garlic extract on budbreak of 'Niagara Rosada' grapevines in two different vineyards. The highest dose of garlic extract (70mL L-1) showed a great potential for budbreak in organic production, presenting similar effects of cyanamides in budbreak. This treatment improved the sprouting percentage, number of clusters, accelerated the beginning of sprouting and reduced the cycle between pruning and harvest.

Nas regiões com invernos amenos, normalmente as exigências de frio para a quebra de dormência de gemas de videiras não são atendidas, e apenas os produtos altamente tóxicos CaCN2 e H2CN2 são recomendados na viticultura convencional para quebra de dormência. A proposta deste estudo foi verificar o efeito do extrato de alho na quebra de dormência de videiras 'Niagara Rosada', em dois diferentes vinhedos. A dose mais elevada de extrato de alho (70mL L-1) demonstrou ter um grande potencial para a quebra de dormência na produção orgânica, apresentando efeitos similares aos das cianamidas, na quebra de dormência. Este tratamento aumentou a porcentagem de brotação e o número de cachos, antecipou o começo da brotação e reduziu o ciclo entre poda e colheita.

Aplicação de reguladores vegetais em uva apirena 'Centennial Seedless' / Growth regulators applied on seedless grape 'Centennial Seedless'

O trabalho objetivou avaliar o efeito de doses crescentes do forchlorfenuron associado ou não ao ácido giberélico sobre componentes físico-químicos da uva 'Centennial Seedless' para consumo in natura. Os tratamentos testados foram ácido giberélico (AG3) (0 e 5mg L-1) associado ao forchlorfenuron (0, 2, 4, 6, 8 e 10mg L-1). As variáveis analisadas foram a massa, o comprimento e a largura dos cachos, das bagas e dos engaços, o teor de sólidos solúveis, o pH, a acidez titulável e a relação sólidos solúveis/acidez titulável (SS/AT). O experimento foi conduzido em vinhedo localizado no município de São Miguel Arcanjo, no sudoeste do Estado de São Paulo, sendo os reguladores vegetais aplicados aos 15 dias após o pleno florescimento, mediante pulverização direcionada ao cacho. A interação entre a dose estimada de 5mg L-1 de forchlorfenuron associada ao AG3 proporcionou os maiores ganhos na massa e na largura das bagas, e as doses estimadas de 4 e 6,5mg L-1 de forchlorfenuron, associadas ao AG3, proporcionaram os menores teores de sólidos solúveis e a relação SS/AT, respectivamente. O tratamento com o uso de AG3 resultou em ganhos no diâmetro dos pedicelos e na massa dos cachos, das bagas e dos engaços, além de incrementar o comprimento e a largura das bagas.

The objective of present research was to evaluate the effects of increasing doses of forchlorfenuron associated, or not, to gibberellic acid on physical and chemical components of the ´Centennial Seedless' grapes. The treatments were gibberellic acid (GA3) (0 and 5mg L-1) associated with forchlorfenuron (0, 2, 4, 6, 8 and 10mg L-1). The variables were mass, width and length of bunches, berries and rachis, total soluble solids, pH, acidity and total ratio soluble solids/titratable acidity (SS/TA). The experiment was conducted in a vineyard located in the municipality of São Miguel Arcanjo, southwest of São Paulo State, and the regulators were applied at 15 days after full bloom by spraying the bunch. The interaction of the estimated dose of 5mg L-1 forchlorfenuron associated with GA3, provided increases on the mass and width of the berries, and the estimated doses of 4 and 6.5mg L-1 of forchlorfenuron associated with GA3, showed the lowest soluble solids and ratio SS/TA, respectively. The treatment with GA3 resulted in gains in the diameter of the pedicels, mass of bunches, berries and rachis, and increasing the length and width of berries.

Avaliação do enraizamento, desenvolvimento de raízes e parte aérea de porta-enxertos de videira em condições de campo / Evaluation of rooting, development of roots and shoot biomass from rootstock of grapevine, in field conditions

Objetivou-se neste trabalho avaliar o enraizamento, a brotação e o desenvolvimento de raízes de diferentes porta-enxertos de videira em condições de campo. Estacas lenhosas dos porta-enxertos '420 A', 'Golia', '5C', '8B', 'RR101-14', 'SO4', '99R', 'Kober 5BB', 'IAC 766', 'IAC 572', 'IAC 571-6', 'Ripária do Traviú' e 'Rupestris du Lot' foram colocadas em canteiro de terra, sem tratamento prévio. O delineamento foi em blocos ao acaso, com cinco repetições e vinte estacas por parcela, com as estacas dispostas em espaçamento de 12 x 5cm. As estacas foram colocadas para enraizar no início de julho e removidas no final de setembro para as avaliações. A porcentagem de estacas enraizadas variou de 79 por cento para 'Ripária do Traviú' a 99 por cento para o 'RR101-14'. Quanto à brotação, o 'Ripária do Traviú' apresentou 47 por cento, 'IAC 571-6', 'IAC 572', '420 A', 'Rupestris du Lot', 'Kober', 'IAC 766', '8B', '5C', apresentaram de 76 a 89 por cento e 'Golia', 'SO4', '99R' e 'RR 101-14' mais de 90 por cento. 'IAC 572' e 'IAC 571-6' apresentaram o menor número de raízes por estaca, no entanto, foram as que apresentaram raízes mais desenvolvidas, seguidas pelo '5C' e 'Rupestris du Lot'. 'Kober 5BB' e 'Ripária do Traviú' apresentaram as raízes menos desenvolvidas. As demais variedades apresentaram valores intermediários. Concluiu-se que, entre todos os porta-enxertos, o 'Ripária do Traviú' apresentou os menores índices de enraizamento e brotação das estacas, nas condições de campo.

The goals of this investigation was to evaluate the rooting, budding and development of roots from different rootstock of grapevine, in field conditions. Ligneous cutting of rootstock '420 A', 'Golia', '5C', '8B', 'RR101-14', 'SO4', '99R', 'Kober 5BB', 'IAC 766', 'IAC 572', 'IAC 571-6', 'Ripária do Traviú' and 'Rupestris du Lot' were planted in soil, without previous preparation. The experimental design was done in randomized blocks, with five repetitions and twenty cutting per plot, planted at distances of 12 x 5cm. The cutting were planted in the beginning of July and removed in the end of September, to be examined. The rooting percentage varied from 79 percent of 'Ripária do Traviú' to 99 percent of 'RR 101-14'. Due to budding, the 'Ripária do Traviú' showed 47 percent; 'IAC 571-6', 'IAC 572', '420A', 'Rupestris du Lot', 'Kober', 'IAC 766', '8B', '5C' showed 76 to 89 percent and 'Golia', 'SO4', '99R' and 'RR 101-14' showed more than 90 percent. 'IAC 572' and 'IAC 571-6' showed the minor root number per cutting, but they showed the most developed roots, followed by '5C' and 'Rupestris du Lot'. 'Kober 5BB' and 'Ripária do Traviú' showed the least developed roots. The other varieties showed intermediate values. It was conclued that, among all rootstocks, 'Ripária do Traviú' presented the lowest indexes of rooting and budding of cutting under field's conditions.