Valmor João Bianchi

Microsatellite markers for identification of Prunus spp. rootstocks

Cultivar characterization for fruit trees certification requires fast, efficient and reliable techniques. Microsatellite markers (SSR) were used in the molecular characterization of 29 Prunus spp. rootstocks. The DNA from the rootstocks was analyzed using five pre-selected SSR primers (UDP96-005, UDP96-008, UDP96-013, UDP96-18 and UDP98-414) and revealed 81 alleles, which allowed each genotype to be identified. The UDP96-005 marker generated the most information, i.e., 23 well-distributed, polymorphic alleles among all genotypes. The 21 polymorphisms produced by UDP96-013 occurred mainly as a result of high degree of variability among genotypes of the Prunophora subgenus. In the dendrogram, the five markers allowed the 29 rootstocks to be grouped into subgroups corresponding to the subgenus they belong to, either Prunophora or Amygdalus. Suitable cophenetic correlation coefficient (r=0.82) and good bootstrapping fitting value among the Prunophora subgroup cultivars were obtained. SSR markers proved to be efficient and reliable for the molecular characterization of Prunus spp. rootostocks.

RAPDs na caracterização genético-molecular e no estudo da variabilidade genética de cultivares de ameixeira

Molecular markers have been used thoroughly in many fruit crops species for fingerprinting analysis during the vegetal material certification process, and as an auxiliary tool in breeding programs to access genetic variability among genotypes. The plum is an important crop in Southern Brazil. The present paper aims to contribute for the genetic-molecular characterization of 17 plum cultivars, which were analyzed with 12 RAPD markers that produced 187 polymorphisms. The OP A20 marker was the most polymorphic, producing 26 different profiles. The cluster analysis was represented by a dendrogram using the UPGMA method, and showed a clear cultivar separation in to three groups corresponding to the species, Prunus salicina, Prunus domestica and Prunus cerasifera, respectively. A high degree of polymorphism was detected by the RAPD markers in the plum. This confirms the potential of the techanique of fingerprinting analysis and its usefulness in the estimate of the genetic variability among plum cultivars.

Prunus transcription factors: breeding perspectives.

Many plant processes depend on differential gene expression, which is generally controlled by complex proteins called transcription factors (TFs). In peach, 1533 TFs have been identified, accounting for about 5.5% of the 27,852 protein-coding genes. These TFs are the reference for the rest of the Prunus species. TF studies in Prunus have been performed on the gene expression analysis of different agronomic traits, including control of the flowering process, fruit quality, and biotic and abiotic stress resistance. These studies, using quantitative RT-PCR, have mainly been performed in peach, and to a lesser extent in other species, including almond, apricot, black cherry, Fuji cherry, Japanese apricot, plum, and sour and sweet cherry. Other tools have also been used in TF studies, including cDNA-AFLP, LC-ESI-MS, RNA, and DNA blotting or mapping. More recently, new tools assayed include microarray and high-throughput DNA sequencing (DNA-Seq) and RNA sequencing (RNA-Seq). New functional genomics opportunities include genome resequencing and the well-known synteny among Prunus genomes and transcriptomes. These new functional studies should be applied in breeding programs in the development of molecular markers. With the genome sequences available, some strategies that have been used in model systems (such as SNP genotyping assays and genotyping-by-sequencing) may be applicable in the functional analysis of Prunus TFs as well. In addition, the knowledge of the gene functions and position in the peach reference genome of the TFs represents an additional advantage. These facts could greatly facilitate the isolation of genes via QTL (quantitative trait loci) map-based cloning in the different Prunus species, following the association of these TFs with the identified QTLs using the peach reference genome.

Enraizamento in vitro do morangueiro (Fragaria x ananassa Duchesne) em diferentes concentrações do meio MS

The present work was carried out in the Tissue Culture Laboratory EMBRAPA/CPACT, Pelotas-RS, with the objective of verifying the behaviour in vitro of two cultivars of strawberry on different MS medium concentration. Strawberry explants, Hofla and Tangi cultivars coming from in vitro culture were tested on MS medium in the full, 3/4 and 1/2 strength suplemented with 30g/l sucrose, 100mg/l myo-inositol and 0.005mg/l benzylanimopurine (BA). Flasks (250ml) containing 40ml of medium culture with five explants per flasks were used. Cultures were maintained in a growth room at 25°C with a photoperiod of 16 h at 1.5 Klux for 32 days. Results indicated that the reduction in MS salts improved rooting explant by increasing the number of roots of the Tangi cultivar. A large root length was obtained with the Hofla cultivar in the 3/4 and 1/2 MS concentration. It was not observed any difference in the development of the plantlets among the cultivars due to the reduction in MS salts.

Enraizamento de estacas do porta-enxerto de marmeleiro (Cydonia oblonga Mill.) cv. EMC, em diferentes substratos, concentrações de ácido indolbutírico e enxertia de raiz

Com este trabalho, objetivou-se testar tecnicas para o enraizamento de microestacas lenhosas de marmeleiro cv. EMC por meio de diferentes substratos, concentracoes de acido indolbutirico (AIB) e a enxertia de raiz. Foram realizados dois experimentos; no experimento 1 testou-se concentracoes de AIB (0, 1000, 2000 e 3000 mg.L-1) e no experimento 2 enxertia de raiz (com e sem enxertia de raiz). Para ambos os experimentos as estacas foram acondicionadas em tres substratos (vermiculita, Plantmaxâ e vermiculita + Plantmaxâ, em proporcao de volume de 1:1) e avaliado o numero e comprimento de raizes e brotos por estacas, percentual de estacas enraizadas e, percentual de sobrevivencia a campo. No experimento 1, verificou-se resposta linear positiva para numero medio de raizes e negativo para numero e comprimento de brotacoes e sobrevivencia a campo, enquanto que nas variaveis comprimento medio de raizes e porcentagem de enraizamento, observou-se comportamento polinomial quadratico, com melhor resposta obtida com 1354 e 2119 mg.L-1 de AIB, respectivamente. No experimento 2, verificou-se que a utilizacao de vermiculita + Plantmaxâ apresentou maior numero de raizes por estaca, quando utilizada enxertia de raiz, porem menor comprimento de brotos. A campo, a melhor resposta foi obtida nas plantas sem enxertia de raiz e oriundas do substrato vermiculita, 93,75%.

ENRAIZAMENTO DE ESTACAS LENHOSAS DE CULTIVARES DE MARMELEIRO (Cydonia oblonga) TRATADAS COM FLOROGLUCINOL

The quince belongs from the family Rosaceae. Now, it has been used as rootstock tree door-graft because it induce dwarf plants. The floroglucinol is a phenolic compost, which effects is by increased the auxine and that tends to induce and to increase hardwoody cuttings. The present work was carried out in a greenhouse with intermittent mist writh the objective to determine the best quince cultivars in relation to its capacity of rooting hardwoody cuttings, and the best floroglucinol concentration for the root induction. The cultivars Pineapple, Meliform, Prolonged, Radaelli, Portugal, Inta and MC were used. They were submitted to three treatments of different floroglucinol concentrations (zero, 1500 and 3000 mg.L-1). The cuttings with 12 cm and ½ leaf in the superior part were conditioned in plastic boxes contends medium vermiculita. The experimental design used random blocks in the factorial arrangement (3 x 7), with 3 repetition and 5 cuttings for replication (15 cuttings for treatments). The analyzed variables were determination of the percentage of rooting, number of roots and percentage of cuttings shottings. It was observed that, independently of the tested concentration, the floroglucinol, did not induce the rooting of hardwoody cuttings of the cultivars tested. Cultivar MC presented better percentage of rooting, number of roots and percentage of shottings.

Fluorescência da clorofila a em plantas de pessegueiro da cultivar maciel enxertada sobre diferentes porta-enxertos

The objective of this study was to evaluate characteristics of chlorophyll fluorescence in peach trees cv. Maciel grafted on six rootstocks. The analysis of the chlorophyll a fluorescence, the chlorophyll content and length of the leaves began after the winter period and were repeated until approximately 150 days, totaling six samples. The early ontogeny of the leaves was characterized by some higher fluorescence parameters. High rainfall, which occurred between 61 and 112 days of the beginning of the experiment, was the environmental factor that caused the greatest change in the parameters of the JIP Test, especially those related to photosystem I. The chlorophyll content was not influenced by the effect of associations cup x rootstock. Fall in the PITOTAL were in the period of highest rainfall, behavior that was independent of the rootstock, except for plants grafted on rootstock Rubira, who had minor damage to the photosynthetic apparatus. In general, rootstocks studied in combination with cv. Maciel did not affect the absorption and utilization of light energy by photosynthetic system.

Rooting and acclimatization of the Japanese plum tree, cv. América

Rooting and acclimatization are limiting steps in plant micropropagation, especially in woody plant species. This study aimed to evaluate the IAA and IBA effect on the in vitro rooting and acclimatization of micropropagated shoots of Japanese plum (Prunus salicina Lindl.) cv. America. Shoots from 3 to 4 cm long were inoculated in MS medium with half salt and vitamin concentrations (MS/2) added with IAA and IBA (0, 0.25, 0.5, 0.75 and 1 mg L-1). After a 20-day period in in vitro cultivation, the shoots were evaluated, and then transferred to a greenhouse, and evaluated after 30 days. At the end of the in vitro cultivation period, no significant interactions were observed for number of roots per shoot and rooting percentage, but a significant effect was recorded for auxin type only, for which shoots grown in media added with IBA showed high values - 0.87 and 41.95%, respectively. A linear increase response from 1.45 to 5.75 cm was verified for root length of shoots cultivated in IBA medium; however, no significant effect was observed, and a 0.86 cm average root length per shoot grown in medium added with IAA was found. After 30 days of acclimatization period, the largest survival percentage was obtained from shoots cultivated in medium with 1 mg L-1 of IBA and IAA (88% and 92%, respectively). Although, IBA provided the highest in vitro rooting, most of the surviving shoots were those originated in IAA-added medium, probably because IBA promoted longer fibrous roots, less appropriate for transplant and soil fixation, as they are easily damaged. It was concluded that in vitro rooting with the addition of the highest IAA concentration (1 mg L-1) provided the greatest plant survival during the acclimatization period of the Japanese plum cv. America.

Teores de carboidratos em estacas lenhosas de mirtileiro

O objetivo do trabalho foi avaliar as alteracoes no teor de carboidratos em estacas lenhosas de mirtileiro das cultivares Delite, Powder Blue e Selecao 19. Foram analisados os teores de amido e de acucares soluveis a partir de ramos coletados em quatro epocas diferentes (03/06, 04/07, 24/07 e 11/08/2008) em um primeiro experimento e, posteriormente, avaliou-se o teor de carboidratos em estacas, coletadas nas mesmas epocas citadas, submetidas a condicoes de enraizamento. Verificou-se que a cv. Powder Blue possui maior reserva amilacea que a cv. Delite e Selecao 19. Estacas lenhosas de mirtileiro com baixos teores de amido, quando submetidas ao enraizamento, apresentam ressintese de amido. No fim do periodo de inverno, ocorre um aumento na concentracao de amido nos ramos lenhosos de mirtileiro. Maior teor de amido nos ramos durante o periodo de inverno esta associado a maior taxa de enraizamento.

Diversidade genética entre acessos de espinheira-santa (Maytenus ilicifolia Mart. ex Reis.) coletados no estado do Rio Grande do Sul, Brasil

Maytenus ilicifolia Mart. ex Reis., popularmente conhecida como espinheira-santa, e especie autoctone pertencente a familia Celastraceae, usada para tratamento de ulceras gastricas e gastrites. Devido a importância medicinal, houve aumento no extrativismo das populacoes naturais, tornando-a uma especie prioritaria para a conservacao, a fim de evitar a erosao genetica. Buscou-se com este trabalho analisar a diversidade genetica de 20 acessos de M. ilicifolia coletados em diferentes localidades no Rio Grande do Sul. Utilizando marcadores moleculares do tipo AFLP, foram testadas oito combinacoes de primers, que geraram 455 bandas eletroforeticas, 100% polimorficas. As combinacoes de primers E-ACC/M-CAA, E-ACG/M-CTA, E-ACG/M-CTC apresentaram o maior numero de bandas eletroforeticas, 71 cada, totalizando 46,80% do polimorfismo total. Os valores de similaridade genetica calculada pelo coeficiente simple matching foram utilizados para gerar o dendrograma de similaridade pelo metodo UPGMA. Foi obtido alto coeficiente de correlacao cofenetica (r=0,94), demonstrando elevada representatividade dos dados de similaridade genetica no dendrograma. Pela AMOVA verificou-se que 89,33% da diversidade total ocorreram entre individuos dentro das populacoes. A caracterizacao molecular de acessos de Maytenus ilicifolia por meio de AFLP foi eficiente para identificar diversidade genetica. Atraves da analise de similaridade genetica o banco de germoplasma poderia ser composto com os acessos que apresentaram menor similaridade e maior numero de alelos, permitindo com que estes fornecessem ampla cobertura do genoma que compoem Maytenus ilicifolia. Os acessos que ficaram agrupados em mesmo cluster e com numero reduzido de alelos podem ser descartados deste banco. A diversidade genetica intrapopulacional identificada por esse marcador foi muito maior do que aquela entre populacoes.