Background: Fruit quality traits have a significant effect on consumer acceptance and subsequently on peach (Prunus persica (L.) Batsch) consumption. Determining the genetic bases of key fruit quality traits is essential for the industry to improve fruit quality and increase consumption. Pedigree-based analysis across multiple peach pedigrees can identify the genomic basis of complex traits for direct implementation in marker-assisted selection. This strategy provides breeders with better-informed decisions and improves selection efficiency and, subsequently, saves resources and time. Results: Phenotypic data of seven F 1 low to medium chill full-sib families were collected over 2 years at two locations and genotyped using the 9 K SNP Illumina array. One major QTL for fruit blush was found on linkage group 4 (LG4) at 40-46 cM that explained from 20 to 32% of the total phenotypic variance and showed three QTL alleles of different effects. For soluble solids concentration (SSC), one QTL was mapped on LG5 at 60-72 cM and explained from 17 to 39% of the phenotypic variance. A major QTL for titratable acidity (TA) co-localized with the major locus for low-acid fruit (D-locus). It was mapped at the proximal end of LG5 and explained 35 to 80% of the phenotypic variance. The new QTL for TA on the distal end of LG5 explained 14 to 22% of the phenotypic variance. This QTL co-localized with the QTL for SSC and affected TA only when the first QTL is homozygous for high acidity (epistasis). Haplotype analyses revealed SNP haplotypes and predictive SNP marker(s) associated with desired QTL alleles. Conclusions: A multi-family-based QTL discovery approach enhanced the ability to discover a new TA QTL at the distal end of LG5 and validated other QTLs which were reported in previous studies. Haplotype characterization of the mapped QTLs distinguishes this work from the previous QTL studies. Identified predictive SNPs and their original sources will facilitate the selection of parents and/or seedlings that have desired QTL alleles. Our findings will help peach breeders develop new predictive, DNA-based molecular marker tests for routine use in marker-assisted breeding.

The strawberry cultivation is an important economic activity in the Rio Grande do Sul State, Brazil, however the number of offered cultivars to the growers is reduced. The yield and quality of strawberry (Fragaria x ananassa Duch.) cultivars Camarosa, Galexia, Earlibrite, Festival, Plarionfre and Sabrosa was evaluated under the climatic conditions of Pelotas, Rio Grande do Sul State. We determined the number, mass, total soluble solids (TSS ºBrix), total titratable acidity (TTA), antocianin level and fresh fruits produced in an experimental unit. We also determined the production of fruits per hectare and per plant. The statistical design used in the experiment was of completely randomized blocks with 6 treatments (cultivars) and 4 replicates where the experimental unit was composed of 8 plants. The harvest began in the first half of August, extending to the second half of December, totalling 20 weeks. Plarionfre, Earlibrite and Festival cultivars showed higher production from the first half of October until the end of the first half of November. Camarosa reached higher productivity, mass of plants and fruit weight. There were no differences between the evaluated cultivars in the levels of TSS, antocianin, ATT and pH during the period of evaluation.

Background Environmental adaptation and expanding harvest seasons are primary goals of most peach [Prunus persica (L.) Batsch] breeding programs. Breeding perennial crops is a challenging task due to their long breeding cycles and large tree size. Pedigree-based analysis using pedigreed families followed by haplotype construction creates a platform for QTL and marker identification, validation, and the use of marker-assisted selection in breeding programs. Results Phenotypic data of seven F1 low to medium chill full-sib families were collected over 2 years at two locations and genotyped using the 9 K SNP Illumina array. Three QTLs were discovered for bloom date (BD) and mapped on linkage group 1 (LG1) (172–182 cM), LG4 (48–54 cM), and LG7 (62–70 cM), explaining 17–54%, 11–55%, and 11–18% of the phenotypic variance, respectively. The QTL for ripening date (RD) and fruit development period (FDP) on LG4 was co-localized at the central part of LG4 (40–46 cM) and explained between 40 and 75% of the phenotypic variance. Haplotype analyses revealed SNP haplotypes and predictive SNP marker(s) associated with desired QTL alleles and the presence of multiple functional alleles with different effects for a single locus for RD and FDP. Conclusions A multiple pedigree-linked families approach validated major QTLs for the three key phenological traits which were reported in previous studies across diverse materials, geographical distributions, and QTL mapping methods. Haplotype characterization of these genomic regions differentiates this study from the previous QTL studies. Our results will provide the peach breeder with the haplotypes for three BD QTLs and one RD/FDP QTL to create predictive DNA-based molecular marker tests to select parents and/or seedlings that have desired QTL alleles and cull unwanted genotypes in early seedling stages.

Mudas de mirtilo apresentam crescimento inicial lento e baixo índice de sobrevivência. Dentre os fatores envolvidos na produção de mudas, a qualidade do substrato é um fator de grande importância. O trabalho foi realizado com o objetivo de avaliar o desenvolvimento de mudas de mirtilo, em diferentes composições de substrato, durante os meses de dezembro de 2005 a março de 2006. Foram utilizadas mudas da cultivar Georgiagem, do grupo highbush, oriundas de multiplicação in vitro. Foram utilizados sete diferentes substratos para a formação das mudas: T1 - Plantmax® (100%); T2 - Plantmax® + perlita (1:1); T3 - solo + composto industrial + perlita (1:1:1); T4 - solo + casca de arroz + terra (1:1:2); T5 - solo + composto industrial + vermiculita (1:1:1); T6 - casca de acácia + terra (1:2); T7 - acícula de pínus + terra - (1:2). Foram avaliados: altura das plantas; acúmulo de matéria seca da parte aérea e raiz, e análise química dos substratos. A composição do substrato influenciou no desenvolvimento das mudas de mirtilo. Os melhores resultados foram observados em substratos com pH ácido. Conclui-se que os substratos acícula de pínus + terra, Plantmax®, Plantmax® + perlita e casca de arroz + terra apresentaram melhores resultados.

Hortic. bras., v34, n. 4, out. -dez. 2016 horticultura horticultura brasileira brasileira O m o r a n g u e i r o ( F r a g a r i a x ananassa) é bastante cultivado no Brasil. No entanto, todas as cultivares utilizadas para a produção de frutas são oriundas principalmente de programas de melhoramento dos Estados Unidos; logo, não existem cultivares desenvolvidas especialmente para as condições de clima e solo brasileiros.O fato destes materiais serem cultivados em um local para o qual eles não foram desenvolvidos faz com que seja necessário avaliá-los, não só quanto à adaptabilidade às condições edafoclimá-ticas e sistema de manejo, mas também quanto à qualidade da fruta para consumo local, pois, além do comportamento produtivo, a qualidade sensorial também pode ser afetada devido a diversos fatores como as interações que ocorrem entre o genótipo e o ambiente (Whitaker, 2011), sistema de cultivo (Camargo et al., 2011), ponto de maturação (Crisosto et al., 2010) e época de colheita (Hasing et al., 2013).Estes estudos são importantes por fornecerem aos produtores e consumidores mais informações sobre a qualidade das frutas, visto que nos últimos anos, a preocupação dos consumidores em relação à qualidade dos alimentos tem crescido bastante.Qualidade de alimento é um conceito complexo e normalmente medido utilizando-se índices objetivos relacionados a características nutricionais, microbiológicas ou físico-químicas, no entanto, quando a qualidade é definida por grau de excelência, nenhum destes índices é adequado (Cardello, 1995), pois qualidade de um alimento é considerada pela maioria dos consumidores como os atributos percebidos pelos sentidos.Entender e identificar os fatores de qualidade percebida pelo consumidor é fundamental quando se pretende não apenas produzir alimentos, mas também comercializá-los ( RESUMONo Brasil as cultivares de morangueiro utilizadas, são oriundas de programas de melhoramento genético de outros países, e apresentam características sensoriais que atendem à demanda do local de origem. Além disto, essas características podem ser variáveis com as condições de clima e solo, bem como, com o sistema de cultivo adotado, sendo de grande importância a avaliação desses materiais no local de cultivo. O objetivo do trabalho foi caracterizar sensorialmente morangos das cultivares Camarosa, Diamante, Aromas, Ventana, Albion, Camino Real, Earlibrite e Festival produzidas em Pelotas-RS. Para tanto, os frutos foram avaliados quanto à aparência, textura e sabor através do Método Descritivo Quantitativo, por uma equipe composta de oito provadores treinados. A cultivar Camino Real mostrou melhor coloração enquanto a 'Earlibrite' se caracterizou pela maior intensidade de brilho e a 'Camarosa' exibiu maior quantidade de defeitos, o que resultou em comprometimento da qualidade visual. A cultivar Albion, seguida da Ventana e da Camino Real apresentou frutos de qualidade superior às demais, além de ter mostrado boas características sensoriais ao serem produzidas na região de Pelotas.Palavras-chave: Fragaria...

RESUMO -O objetivo do trabalho foi verificar a viabilidade e definir um substrato adequado para o enraizamento de microestaquia e o crescimento de mudas de mirtileiro cultivar Georgiagem. Foram avaliados diferentes substratos para a técnica de microestaquia mantida em condições de microambiente úmido, com temperatura e luz controladas. As microestacas foram acondicionadas em caixas de politereftalato de etileno, durante 48 dias. Os substratos turfa de musgo Sphagnum sp. e as misturas turfa + perlita, turfa + perlita + fibra de coco, turfa + perlita + serragem permitiram a obtenção de maior percentual de enraizamento. Termos de indexação: substratos, rejuvenescimento, Vaccinium, microestaquia, Southern highbush. SUBSTRATES FOR ROOTING MICROCUTTING BLUEBERRRY CULTIVAR GEORGIAGEMABSTRACT -The aim this research was check the viability end to determine a suitable substrate for rooting by microcutting technique and blueberry plant growth cultivar Georgiagem. The microcuttings were kept under moist micro-environment conditions at both regulated temperature and light. The microcuttings were kept in to boxes of ethylene polvtereftalate, during 48 days. The substrates Sphagnum sp. peat moss and the mixes of peat + perlite, peat + perlite + coconut fiber and peat + perlite + sawdust allowed higher rooting percentage.

BackgroundEnvironmental adaptation and expanding harvest seasons are primary goals of most peach [Prunus persica (L.) Batsch] breeding programs. Breeding perennial crops is a challenging task due to their long breeding cycles and large tree size. Pedigree-based analysis using pedigreed families followed by haplotype construction creates a platform for QTL and marker identification, validation, and the use of marker-assisted selection in breeding programs.ResultsPhenotypic data of seven F1 low to medium chill full-sib families were collected over two years at two locations and genotyped using the 9K SNP Illumina array. Three QTLs were discovered for bloom date (BD) and mapped on linkage group 1 (LG1) (172 – 182 cM), LG4 (48 – 54 cM), and LG7 (62 – 70 cM), explaining 17-54%, 11-55%, and 11-18% of the phenotypic variance, respectively. The QTL for ripening date (RD) and fruit development period (FDP) on LG4 was co-localized at the central part of LG4 (40 - 46 cM) and explained between 40-75% of the phenotypic variance. Haplotype analyses revealed SNP haplotypes and predictive SNP marker(s) associated with desired QTL alleles and the presence of multiple functional alleles with different effects for a single locus for RD and FDP.ConclusionsA multiple pedigree-linked families approach validated major QTLs for the three key phenological traits which were reported in previous studies across diverse materials, geographical distributions, and QTL mapping methods. Haplotype characterization of these genomic regions differentiates this study from the previous QTL studies. Our results will provide the peach breeder with the haplotypes for three BD QTLs and one RD/FDP QTL for the creation of predictive DNA-based molecular marker tests to select parents and/or seedlings that have desired QTL alleles and cull unwanted genotypes in early seedling stages.

Ten phenological and fruit quality traits were evaluated in seedlings from nine F1 low to medium chill full-sib peach (Prunus persica) families and their parents over 2 years at two locations (Fowler, CA, and College Station, TX) to estimate variance components, genotype by environment interaction (G×E), and phenotypic correlations using restricted maximum likelihood mixed and multivariate models. The removal of nectarine [P. persica var. nucipersica (fruit without fuzz)] and pantao (flat shape fruit) seedlings from the analysis decreased the heritability for the fruit size, blush, tip, and soluble solids concentration (SSC), indicating the importance of taking the effects of the major gene of nectarine/pantao into account when assessing the heritability of traits. A strong correlation coefficient (r = 0.92) found between ripe date (RD) and fruit development period (FDP) and between fruit weight (FW) and fruit diameter (FD), indicates that either measure is equally effective, although the negative correlation between bloom date (BD) and FDP (r = −0.46) implies earlier blooming during cool temperatures tends to extend FDP. FW, FD, blush, and SSC had moderately weak correlations with RD (r = 0.56, 0.53, −0.41, and 0.48) and FDP (r = 0.57, 0.56, −0.50, and 0.39, respectively), which could be explained either by the presence of a strong link between quantitative trait loci of these traits and the ripening date locus or the pleiotropic effect of ripening date on many quantitative fruit characters. The traits RD, FDP, and titratable acidity (TA) had the highest broad-sense heritability (H2) and lowest G×E. FW, tip, and shape showed the lowest H2, the highest of G×E variance to the genetic F (G×E variance/total genotypic variance), and high G×E, whereas the other traits showed moderate G×E. For the traits that had a higher G×E interaction, selection for or against these traits should be done at the production location. A moderate narrow-sense heritability (h2) was estimated for BD, blush, fruit tip, and shape. FW and FD showed low to moderate h2 while H2 was high, whereas RD, FDP, SSC, and TA showed low h2 and high H2 estimates, indicating important nonadditive effects for these traits.