Maria do Socorro Padilha de Oliveira

Seleção de progênies de maracujazeiro-amarelo (Passiflora edulis f. flavicarpa) quanto à qualidade de frutos

Para garantir a sustentabilidade da cultura do maracujazeiro, na Amazonia, e imprescindivel realizar pesquisas que busquem o desenvolvimento de cultivares tolerantes as principais doencas e que apresentem frutos com boas caracteristicas agroindustriais. Este trabalho teve por objetivo avaliar frutos de progenies de maracujazeiro-amarelo, CPATU-casca-fina (CCF), atraves de caracteristicas fisicas e fisico-quimicas, buscando obtencao de plantas com caracteristicas desejaveis para industria de suco concentrado e fruto in natura. O estudo foi conduzido em 20 progenies de polinizacao livre oriundas de uma populacao formada pela mistura de sementes de plantas selecionadas no segundo ciclo de selecao massal. Colheram-se dez frutos por planta para serem analisados, com base nas seguintes caracteristicas: peso medio dos frutos; comprimento do fruto; espessura de casca; rendimento de suco; numero de sementes por fruto; teor de solidos soluveis totais (SST); acidez total titulavel (ATT); pH e relacao STT/ATT. Os dados obtidos foram analisados atraves de estatistica simples, envolvendo media, desvio-padrao e coeficiente de variacao. As progenies CPATU-casca-fina apresentaram variacao para a maioria das caracteristicas. Os frutos das progenies CCF-001, CCF-074, CCF-212, CCF-395 e CCF-430 apresentam caracteristicas desejaveis para o mercado in natura, enquanto os das progenies CCF-192, CCF-281, CCF-391 e CCF-505 tem caracteristicas importantes para a industria de suco concentrado.

Diversidade genética entre acessos de açaizeiro baseada em marcadores RAPD

One characterized the genetic diversity among accessions of assai palm using RAPD markers. One hundred and sixteen accessions conserved in the Embrapa Eastern Amazon germplasm collection, in Belem, PA, were analyzed using 28 primers. The data of the binary matrix were used to estimate the genetic dissimilarities using the arithmetical complement of Dice similarity coefficient and also for the bootstrap analysis. The genetic dissimilarities were represented in a dendrogram generated by the UPGMA method. The primers revealed 263 polymorphic RAPD loci presented wide genetic diversity among the accessions, varying from 0,06 to 0,67, being two accessions of the Chaves, PA the most divergent. But, some accessions of the same origin presented low dissimilarities. The dendrogram allowed the formation of eight groups delimited by the genetic mean dissimilarity (dgm: 0,40): two formed by a single accession; two constituted by two accessions and the others for several sub-groups with accessions of different origin. The ideal number of bands for estimating the genetic diversity among 116 accessions was 180. Therefore, the number of bands used in this study was efficient to characterize with precision the genetic relationship among the accessions of assai palm. The accessions divergent should be useful in the formation of nuclear collections and genetic breeding.

REPETIBILIDADE DE CARACTERES DO CACHO DE AÇAIZEIRO NAS CONDIÇÕES DE BELÉM-PA

Was considered the repeatibility coefficient in characters of raceme in acai palm (Euterpe oleracea Mart.) at Belem-PA with the intention of determining their capacity to express the genetic variability of that fruit bowl. For that were picked four racemes by plant, all presenting complete maturation, in 30 genotypes belonging to the Collection of Germplasm of Acai palm of Oriental Amazonian Embrapa, where six characters were evaluated: weight of the raceme (PTC), weight of fruits per raceme (PFC), number of fruits per raceme (NFC), rachilles number per raceme (NRC), weigh medium of the fruit (PMF) and revenue of fruits ber raceme (RFC). The analysis of the repeatibility, of the number of necessary measurements and of the coefficient determination for each character was obtained through the method of the variance analysis using the model with two variation factors. It was verified that all the characters presented significant differences among genotypes, with the number of fruits, rachilles number and medium weight of the fruit being at the level of 1% of probability. However, the largest repeatibility coefficient was registered for medium weight of the fruit, while the others presented inexpressive values. That variable also had the largest determination coefficient. Meanwhile to the number of replications desirable for that character should be almost the triple of used in this study. The fact of the repeatibility coefficient expresses the maximum value of heritability can be concluded that PMF could be used as a selection parameter in less rigorous improvement methods.

Biologia da polinização da palmeira tucumã (Astrocaryum vulgare Mart.) em Belém, Pará, Brasil

Estudaram-se alguns aspectos da biologia da polinizacao da palmeira tucuma em uma area experimental da Embrapa Amazonia Oriental, em Belem, PA. Foram coletados dados de fenologia, morfologia floral, duracao da floracao, viabilidade polinica e visitantes florais em dez plantas, no periodo de janeiro a dezembro/1997. Trata-se de uma palmeira arborea, multicaule, monoica, que possui inflorescencia envolvida por uma bractea lenhosa coberta por espinhos e centenas de flores unissexuais, sesseis. A flor feminina e ladeada por duas masculinas formando a triade, localizando-se na base das raquilas; creme e medindo de 5 a 10mm compr.; do tipo campanular, com petalas aderidas ao estigma. As flores masculinas ocorrem em maior quantidade e medem de 2 a 4mm compr. Eventos de floracao e de frutificacao foram registrados em todo o periodo, com picos de marco a julho e de dezembro a marco, respectivamente. A abertura da bractea e exposicao da inflorescencia ocorreu, principalmente, no inicio da manha e da noite, periodos em que todas as flores femininas iniciam a antese, com o estigma apresentando secrecao pegajosa, permanecendo receptivas por 24 a 36h. As flores masculinas tambem apresentaram antese simultânea e noturna, ficando viaveis por 24 a 36h, permanecendo aderidas as raquilas por varios dias. A viabilidade polinica foi alta, tanto em botoes em pre-antese como em flores abertas. As recompensas florais foram o polen em abundância e a secrecao estigmatica. Varias partes da inflorescencia, principalmente as flores, emitiram forte odor. Os visitantes florais foram insetos, com predominância de besouros e abelhas. Portanto, a palmeira tucuma e uma especie protoginica, com polen e forte odor como atrativos primarios e polinizacao predominantemente cantarofila.

Estimativas de parâmetros genéticos e ganhos de seleção em progênies de polinização aberta de açaizeiro

The present work aimed to study the genetic variability, estimate the genetic and phenotypic parameters and to conduct the prediction of genetic values of individuals of irrigated acai tree in the state of Para. The objective was the selection and genetic improvement of the production of fruits, using the REML/BLUP procedure applied in the progenies for the characters height of the first cluster, total cluster mass, total fruit mass, number of clusters, mean cluster weight, average length of the leaf rachis, average number of rachillas, number of tillers and average mass of one hundred fruits. Fifty progenies were evaluated in two 5 x 5 lattice design with two replications and linear plots- of five plants each, in a 5 m x 5 m spacing. The software Selegen- Reml/Blup was used for the genetic analyses and identification of the best individuals to compose the population for seed production (short-term program) and of improvement (long-term program). The estimation of genotipic correlation was high between total fruit mass and number of cluster and average among total fruit mass and average cluster mass and number of rachillas. The estimates of the genetic parameters obtained in the present study show excellent selective potential of the population and sufficient genetic variability for the genetic improvement of the population in short and long terms. Considerable genetic gain of 45.33% relative to the average of the experiment can be obtained with the election of the 20 best individuals for the character total production of fruits.

CULTURA IN VITRO DE EMBRIÕES ZIGÓTICOS DE AÇAIZEIRO

This work had as objective to establish protocol for the production of seedlings in vitro from of the conversion of assai palm zygotic embryos (Euterpe oleracea Mart.). The mature zygotic embryos obtained of seeds of mature fruits were excised under aseptic conditions, and cultivated in rehearsal tubes with 10 mL of a MS medium modified by the presence of 0,17 g.L-1 of NaH2PO4, with agar 0,6%, 0,25% activated charcoal and 3% sucrose. Different combinations of NAA were tested (0,54; 2,68 and 5,37 mM) and BAP (0,44; 1,11; 1,55 and 2,22 mM) and a treatment without growth regulator. On the average, the constituted treatments of ANA and BAP were superiors the to a treatment without growth regulator to all the parameters. The concentrations of 0,54 and 2,68 mM of NAA promoted, on the average, larger formation of normal seedlings when compared with 5,37 mM NAA. The presence of 2,68 mM NAA plus 1,11; 1,55 and 2,22 mM BAP was induced largest shoot length. Significant differences were not verified between NAA and BAP concentrations for the number of roots/seedlings. The obtained results allowed verifying that an addition of NAA and BAP in the culture medium was necessary to the conversion of mature zygotic embryos in both vigorous and normal seedlings.

Seleção simultânea em progênies de açaizeiro irrigado para produção e peso do fruto

Para obtencao de materiais superiores, e necessario que o genotipo selecionado reuna, simultaneamente, uma serie de atributos favoraveis que satisfacam as exigencias dos consumidores, produtores e processadores. Foram analisadas 50 progenies de acaizeiro conduzidas em dois delineamentos tipo latice, com duas repeticoes e cinco plantas por parcela, por um periodo de tres safras, para as caracteristicas de producao e peso de cem de frutos. O objetivo deste trabalho foi estimar parâmetros geneticos e fenotipicos e realizar a predicao de valores geneticos dos individuos e progenies de acaizeiro irrigado no Estado do Para, visando a selecao e ao melhoramento genetico simultâneo para as caracteristicas citadas, empregando a metodologia REML/BLUP. Foram empregados na selecao e na estimativa dos ganhos preditos, os indices com base na media de postos (ranks) e niveis independentes de eliminacao, empregando uma intensidade de selecao de 20 %. Foi obtido ganho genetico de 20,76 % em relacao a media do experimento com a selecao dos 20 melhores individuos para producao de frutos. Acima de cinco medicoes ou safras na avaliacao de progenies de acaizeiro para producao de frutos, pouco acrescentara em termos de eficiencia seletiva, sendo entao injustificado seu uso. O indice com base na media de postos (rank) revelou-se o mais eficiente em selecionar, simultaneamente, progenies superiores para producao e menor peso de frutos, sendo recomendado seu uso em programa de melhoramento genetico do acaizeiro.

Divergência genética entre acessos de açaizeiro fundamentada em descritores morfoagronômicos

The objective of this research was to estimate the genetic divergence among accessions of the assai palm, sampled in the germplasm collection of Embrapa Amazonia Oriental based on morphoagronomic traits, at Belem, PA. The 22 morphoagronomic traits were evaluated in 87 accessions, from 1995 to 2001. Among the 22 traits, seven were relative to the plant, three to the flowering, three to the fruit, and nine to the fruit production. The traits were analyzed using univariate and multivariate analysis. The estimates of the dissimilarities were obtained by the average Euclidian distance with standardized data, and the groupings by UPGMA and Tocher methods. The accessions presented high variation index in the majority of the characters. Genetic distances among accession pair varied from 0.09 to 1.87, with average of 1.39. The method UPGMA divided the accessions into five groups, while the Tocher method formed 24 groupings. The five accessions indicated as more divergent must be used in breeding programs aiming at the obtention of superior genotypes.

Somatic embryogenesis from zygotic embryos of Euterpe oleracea Mart.

O objetivo do presente trabalho foi estudar as diferentes respostas morfogeneticas de embrioes zigoticos de acaizeiro (Euterpe oleracea Mart.) submetidos a varias condicoes de cultura in vitro. Os experimentos foram conduzidos em laboratorio, com material vegetal coletado de plantas de acai da Embrapa Amazonia Oriental, Belem-PA, Brasil. Foi possivel verificar a expressao de um modelo de embriogenese somatica direto, repetitivo e assincronizado em embrioes zigoticos maduros cultivados em meio primario MS, suplementado com 339,36 mM de 2,4-diclorofenoxiacetico (2,4-D), e transferidos para meio secundario MS na presenca de 0,537 mM de acido 1-naftalenoacetico (ANA) e 12,30 mM de 2-isopenteniladenina (2iP). A conversao de embrioes somaticos em plântulas foi alcancada aos 210 dias da inoculacao com a transferencia das culturas para um terceiro meio com a concentracao de sais e sacarose reduzida pela metade e ausencia de reguladores de crescimento.

Influência da posição de semeadura na germinação, vigor e crescimento de plântulas de bacabinha (Oenocarpus mapora Karsten - Aecaceae)

Oenocarpus mapora Karsten it is a type of palm tree that is native in Amazonia. The fruit is used for manufacture of juice, ice creams and creams. With the objective to verify the effect of the sowing position on the germination, vigor and seedlings length, the present experiment was accomplished, being tested four sowing positions with three replicates with 25 seeds per parcels and installed in a completely randomized design. The results showed that the germination of Oenocarpus mapora, seeds was not affected by the sowing position, showing by values above to 92%, however, the when seeds were placed to germinate with the germination pore gone back to the surface, they germinated in smaller time. The initial development of the seedling was influenced by the sowing position.