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Euterpe precatoria (Acai-do-Amazonas) produces fruits of which the fresh pulp is consumed. It is almost exclusively collected by extractivist farmers, because no selected genotypes are available for the establishment of plantations. For the domestication and breeding of the species, mating system studies are needed for strategy formulation. This study evaluated the mating system of a natural population of E. precatoria. Thirteen progenies were genotyped with 13 microsatellite loci by capillary electrophoresis in an automated DNA sequencer. Estimates of single-locus and multilocus outcrossing rates were 1.0, and paternity correlation was low (r^p(m)>= 0.293). Euterpe precatoria families consist mainly of half-sibs and the reproductive strategy of the species is allogamy.

Euterpe precatoriais a palm tree belonging to the Arecaceae family, occurring in Western and Central Brazilian Amazonia. Its fruit, which is very appreciated in the Amazon region, produces pulp that is consumed in fresh form. Its production is carried out almost exclusively by extractive farmers. In order to establish adequate strategies to sustain this genetic resource, we need knowledge about the diversity and genetic structure in natural populations. This study aimed to evaluate the influence of geographic distance on genetic structure in the main extractive populations ofE. precatoriain the Brazilian Amazon. Leaves from 377 plants were collected in 19 populations located in 16 municipalities in the State of Amazonas and three in the State of Rondônia. Twelve microsatellite loci were used to genotype the plants. The diversity and genetic structure among populations were estimated. The average number of alleles per locus was 5.97. The observed heterozygosity means (HO) were higher than expected (HE) at the population level (HO= 0.72,HE= 0.66) and fixation index (f= -0.100) was negative. TheFSTvalue (0.1820) and the AMOVA results (Φ= 0.1796) showed population structure. The populations were clustered into three groups (K= 3) in the Bayesian analysis. The Discriminant Analysis of Principal Components (DAPC) confirmed eight clusters, with the populations close to those identified by the Bayesian analysis. The geographic differentiation was confirmed by the groupings obtained in the Structure analysis and the DACP function. Information related to phenotypic, genetic and environmental characterization of populations is important to guide conservation and management strategies and the formulation of public species management policies in Amazonia.

Made available in DSpace on 2019-10-03T18:20:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-11-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fundacao de Amparo a Pesquisa do Estado do Amazonas Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Project PROPALMA Euterpe precatoria, known as acai do Amazonas, is a regionally important palm of the Amazon rainforest for the fruit production through extractive agriculture. Little information is available with regard to genetic diversity, gene flow, and spatial genetic structure (SGS) of acai populations, which are essential for the use, management, and conservation of genetic resources of the species. This research aimed to assess the genetic diversity, inbreeding level, SGS, and gene flow in four ontogenetic stages of a natural E. precatoria population in the Brazilian Amazon, based on 18 microsatellite loci. The study was carried out in a natural population dispersed in an area of about 10 ha. Leaf tissues of 248 plants were mapped and sampled and classified into four ontogenetic stages: reproductive (59), immature (70), young (60), and seedling (59). Genetic diversity indices were high for all ontogenetic stages. The fixation index (F) for all ontogenetic stages was not significantly different from zero, indicating the absence of inbreeding. A significant SGS was found for all ontogenetic stages (68-110 m), indicating seed dispersal over short distances. Paternity analysis detected pollen immigration of 39.1%, a selfing rate of 4.2%, and a mean pollen dispersal distance within the population of 531 m. The results indicate substantial allele input in the population via pollen immigration, contributing to the maintenance of the genetic diversity of the population. However, within a population, the renewal with new progenies selected from seed plants spaced at least 110 m apart is important to avoid collecting seeds from related plants. Univ Fed Amazonas, Inst Ciencias Exatas & Tecnol, Itacoatiara, AM, Brazil Univ Sao Paulo, ESALQ, Dept Genet, Piracicaba, SP, Brazil Inst Florestal Sao Paulo, Secao Melhoramento & Conservacao Genet Florestal, Sao Paulo, SP, Brazil Univ Fed Amazonas, Fac Ciencias Agr, Manaus, AM, Brazil Embrapa Amazonia Ocidental, Manaus, AM, Brazil Univ Estadual Paulista, Inst Pesquisa Bioenergia, Rio Claro, SP, Brazil Univ Sao Paulo, ESALQ, Dept Ciencias Florestais, Piracicaba, SP, Brazil Univ Estadual Paulista, Inst Pesquisa Bioenergia, Rio Claro, SP, Brazil FAPESP: 2014/10947-8 Fundacao de Amparo a Pesquisa do Estado do Amazonas: 062.00669/2015 Project PROPALMA: 01.10.0343.00

Euterpe precatoria, known as açaí do Amazonas, is a regionally important palm of the Amazon rainforest for the fruit production through extractive agriculture. Little information is available with regard to genetic diversity, gene flow, and spatial genetic structure (SGS) of açaí populations, which are essential for the use, management, and conservation of genetic resources of the species. This research aimed to assess the genetic diversity, inbreeding level, SGS, and gene flow in four ontogenetic stages of a natural E. precatoria population in the Brazilian Amazon, based on 18 microsatellite loci. The study was carried out in a natural population dispersed in an area of about 10 ha. Leaf tissues of 248 plants were mapped and sampled and classified into four ontogenetic stages: reproductive (59), immature (70), young (60), and seedling (59). Genetic diversity indices were high for all ontogenetic stages. The fixation index (F) for all ontogenetic stages was not significantly different from zero, indicating the absence of inbreeding. A significant SGS was found for all ontogenetic stages (68–110 m), indicating seed dispersal over short distances. Paternity analysis detected pollen immigration of 39.1%, a selfing rate of 4.2%, and a mean pollen dispersal distance within the population of 531 m. The results indicate substantial allele input in the population via pollen immigration, contributing to the maintenance of the genetic diversity of the population. However, within a population, the renewal with new progenies selected from seed plants spaced at least 110 m apart is important to avoid collecting seeds from related plants.

Heart of palm harvesting and exploitation has reduced the natural reserves of açaí and juçara; hence, the peach palm is an excellent option as source of heart of palm that can reduce the pressure on these two species. The peach palm has high tillering and no post-harvest oxidation. An experiment in a randomized block design with 72 progenies of peach palm, 36 replications and a single tree plot was performed for five years at the experimental field of Embrapa in the Western Amazon. Genetic parameters were estimated using two mixed models, one based on progeny means and the second on joint information from crops. A repeatability analysis, genotype selection, and progeny selection were performed; the Mulamba and Mock selection index was determined; and Tocher’s clustering method was applied. The repeatability analysis revealed the existence of genetic variability, low repeatability, which ranged from 0.3307 to 0.6698 for five years. The analysis performed through the progeny means showed a heritability that varied from 51% to 23% for in all variables; the clustering revealed two groups. The progeny selection should be the main selection strategy, and crosses of superior progenies of different groups should be emphasized. RESUMO. A coleta de palmito via extrativismo vem reduzindo as reservas naturais de açaí e juçara, sendo o palmito de pupunha uma excelente opção para obtenção de palmito plantado, pois além de diminuir a pressão da exploração extrativista sobre essas duas espécies, possui alto grau de perfilhamento e não apresenta oxidação pós-colheita. Foram testadas 72 progênies de pupunheira, em cinco anos, no campo experimental da Embrapa Amazônia Ocidental, em delineamento blocos casualizados com 36 repetições e uma planta por parcela. Os parâmetros genéticos foram estimados através de modelos mistos (REML/BLUP), foram também realizadas análises de repetibilidade, seleção de progênies, seleção de indivíduos por meio de BLUP individual, índice de seleção Mulamba-Rank e agrupamento de otimização de Tocher. As análises realizadas revelaram a existência de variabilidade genética, baixa repetibilidade, variando de 0,3307 até 0,6698 para cinco anos e herdabilidades variando de 51% a 23% para seleção de progênies nas variáveis analisadas, o agrupamento revelou dois grupos distintos. A seleção de progênies deve ser a principal estratégia de seleção e cruzamentos entre progênies superiores de grupos diferentes devem ser enfatizados.

Background Astrocaryum aculeatum is a palm tree species native to the tropical regions of South America, exploited commercially by local farmers for the pulp extracted from its fruits. The objective of this research was to compare the genetic diversity between adult plants and seedlings from open-pollinated seeds, quantify the pollen flow and dispersal, the spatial genetic structure, and the effective size of a population that has been continuously harvested for its fruits. The study was carried out in a natural population of A. aculeatum distributed over approximately 8 ha in the State of Amazonas (Brazil), separated by 400 m from the closest neighboring population. In total, 112 potential pollen donors, 12 mother plants and 120 offspring were mapped and genotyped. Results Genetic diversity was high for parents and the offspring. The fixation indexes for adults (F = -0.035) and offspring (F = -0.060) were negative and not significant. A significant spatial genetic structure was detected for the adult plants (up to the distance of 45 m) indicating short-distance seed dispersal. Paternity analysis detected 9.2 % of pollen immigration and the average distance of pollination within the population was 81 m. The average effective pollination neighborhood area between plants was 1.51 ha. Conclusions Our results indicate that substantial introduction of new alleles has occurred in the population through pollen immigration, contributing to the maintenance of genetic diversity. Conservation efforts aimed at maintaining the gene pool of the current population or establishing new populations should utilize offspring from mother plants selected to be spaced by at least 50 m to prevent collecting seeds from relatives.

A germinação rápida e uniforme das sementes, seguida por pronta emergência das plântulas são características altamente desejáveis na formação de mudas. O objetivo deste trabalho foi avaliar o efeito da procedência das sementes, da frequência de troca de água para a hidratação e de choques de temperatura sobre a germinação e a produção de plântulas de tucumã-do-amazonas (Astrocaryum aculeatum). Os frutos foram obtidos em três locais do Estado do Amazonas: Mercado de Manaus e região de Maués e do Tarumã-Açu. Após limpeza e secagem dos pirênios e extração das sementes, essas foram submetidas à embebição por 15 dias com troca de água: uma e duas vezes ao dia. Após a embebição, foram aplicados os seguintes tratamentos: testemunha sem imersão em H2O; imersão em H2O a 50 e 10ºC por 5 minutos; imersão em H2O a 50ºC por 5 minutos, seguida por 10ºC por mais 5 minutos; imersão em H2O a 10ºC por 5 minutos, seguida por 50ºC por mais 5 minutos. Os tratamentos foram avaliados por meio de pré-germinação, emergência de plântulas no viveiro e produção de mudas. O experimento foi conduzido no delineamento inteiramente ao acaso, com os tratamentos distribuídos em arranjo fatorial 3 x 2 x 5 (locais de procedência x frequências de troca de água x tratamentos de temperatura), em quatro repetições e cinco sementes por parcela. A frequência de troca de água de embebição da semente e a exposição a choques de temperaturas não tem efeito sobre o desempenho germinativo. A procedência de sementes de tucumã-do-amazonas tem efeito na germinação e na produção de mudas. Rapid, uniform seed germination followed by prompt seedling emergence are highly desirable characteristics in seedling production. The aim of this study was to evaluate the effect of seed origin, frequency with which hydration water was changed and thermal shocks on germination and production of tucumã-do-amazonas (Astrocaryum aculeatum) seedlings. Fruits were obtained from three locations in the state of Amazonas: Manaus market, and in Maués and Tarumã-açú. After cleaning and drying the endocarps and removing them, the seeds were soaked for 15 days, changing the water once or twice a day. After soaking, the following treatments were applied: control without immersion in H2O, immersion for 5 minutes in H2O at 50ºC or 10ºC; immersion for 5 minutes in H2O at 50ºC, followed by a further 5 minutes at 10ºC; immersion for 5 minutes in H2O at 10ºC, followed by a further 5 minutes at 50ºC. Treatments were evaluated by pre-germination, seedling emergence in the nursery and seedling production. The experiment was conducted in totally randomized design with treatments arranged in a factorial 3 x 2 x 5 (places of origin x water exchange frequency x temperature treatments) in four replications of five seeds per plot. Germination performance was not affected by the water exchange frequency, nor by exposure to thermal shocks. The origin of tucumã-do-amazonas has effect over the germination and seedling production.

The Amazonian Tucumã palm (Astrocaryum aculeatum) produces edible fruit, traditionally consumed in indigenous communities and increasingly in urban centers. The species is incipiently domesticated and little studied, despite its growing economic importance for smallholder farmers and gatherers. Studies on the mating system are required for the conservation and use of the species' genetic resources. Our objective was to estimate mating system parameters of the Tucumã palm using microsatellite markers. Plants of 11 progenies of a spontaneous population were genotyped with eight microsatellite loci and the mating system parameters estimated. The population outcrossing rate was estimated at 0.978, and ranged from 0.774 to 1at the family level. The estimates of the correlation of paternity (0.176 and 0.205) suggest a low probability of full-sibs within progenies. Tucumã palm is a predominantly allogamous species and the open-pollinated progenies consist predominantly of half-sibs. A palmeira Astrocaryum aculeatum produz frutos comestíveis, utilizados na alimentação por populações indígenas, tradicionais e urbanas. Esta espécie é incipientemente domesticada e pouco estudada apesar de sua importância econômica para pequenos produtores e extrativistas. Estudos do sistema reprodutivo são necessários para conservação e uso dos recursos genéticos da espécie. O objetivo foi estimar parâmetros do sistema reprodutivo do tucumã-do-Amazonas usando marcadores microssatélites. Plantas de 11 progênies de uma população espontânea foram genotipadas com oito locos de microssatélites e os parâmetros do sistema de cruzamento estimados. A estimativa da taxa de cruzamento populacional foi de 0,978, enquanto ao nível de família variou de 0,774 a 1,283. Os valores da correlação de paternidade, 0,176 e 0,205, indicam baixa probabilidade da ocorrência de irmãos completos dentro das progênies. O tucumã-do-Amazonas é predominantemente alógama e as progênies de polinização aberta são constituídas predominantemente por meio-irmãos.

Application of organic fertilizers and charcoal increase nutrient stocks in the rooting zone of crops, reduce nutrient leaching and thus improve crop production on acid and highly weathered tropical soils. In a field trial near Manaus (Brazil) 15 different amendment combinations based on equal amounts of carbon (C) applied through chicken manure (CM), compost, charcoal, and forest litter were tested during four cropping cycles with rice (Oryza sativa L.) and sorghum (Sorghum bicolor L.) in five replicates. CM amendments resulted in the highest (P

O matrinxã (Brycon cephalus - Gunther, 1869), é uma espécie de peixe nativa da bacia Amazônica que tem despertado grande interesse entre pesquisadores e piscicultores de todo o Brasil. A crescente demanda pelo cultivo desta espécie em ambiente controlado se deve, principalmente, à sua pronta adaptação ao cativeiro e à aceitação de alimentos artificiais, tanto de origem vegetal quanto animal, ao lado do seu elevado valor comercial. Contudo, para ser um empreendimento comercial bem sucedido, o alimento a ser fornecido a esta espécie deve atender a suas necessidades em proteína e permitir elevados ganhos de peso em períodos curtos. O experimento foi conduzido na estação de aqüicultura da Embrapa Amazônia Ocidental. Foram testados cinco níveis de proteína bruta (16, 19, 22, 25 e 28%) em dietas isocalóricas (EB = 390 kcal/100g) em um delineamento experimental inteiramente casualizado com três repetições para cada tratamento. Os resultados obtidos após 210 dias de estudo mostraram que a dieta contendo 28 % de proteína bruta promoveu o maior ganho de peso, melhor conversão alimentar e mais alto crescimento corporal entre os níveis testados, indicando que este nível protéico atendeu satisfatoriamente às necessidades de proteína para esta espécie, nas condições deste experimento. Matrinxã (Brycon cephalus - Gunther, 1869) a native fish species from the Amazon basin, has been causing a great deal of interest among researchers and fish culturists all over Brazil. The rising demand for the culture of this species in controlled environment is mainly due, to its ready adaptation to captivity, the acceptance of manufactured feed made with either animal or plant ingredients, along with its high commercial value. However, for a successful commercial enterprise, feed must meet protein requirements of the fish to allow high weight gain in a short period. The experiment was carried out at Embrapa Amazônia Ocidental aquaculture station. Five crude protein concentration (16, 19, 22, 25 and 28 %) in isocaloric (EB = 390 kcal/100g) diets were tested in a fully randomized experimental design with three replicas. Results obtained at the end of 210 days of study showed that diets containing 28 % crude protein promoted the highest weight gain, growth and best feed conversion among tested diets, indicating that the protein requirements for this species can be satisfactorily achieved under experimental conditions.

Astrocaryum jauari is a non-domesticated palm that is exploited by poachers. Our objective was to investigate the organization of the genetic diversity and structure of three A. jauari populations. The study was carried out in the state of Amazonas, between the municipalities of Coari and Manaus. Nine microsatellite loci were used for the genetic analyses. High genetic variation was found, with a mean number of alleles per locus varying from 3.9 to 4.4. The average observed heterozygosity, varying from 0.71 to 0.78, was higher than expected. No spatial genetic structure was detected, since only one cluster was observed. Our results indicate a possible dispersion strategy and suggest that conservation measures of this species should focus mainly on the populations found at the end of the main river (Solimões) where most of the plant material originating from the headwaters of the tributaries of this river is concentrated. © 2014 Brazilian Society of Plant Breeding. All rights reserved.

Multistrata agroforestry systems with tree crops comprise a variety of land use systems ranging from plantations of coffee, cacao or tea with shade trees to highly diversified homegardens and multi-storey tree gardens. Research on plant-soil interactions has concentrated on the former. Tree crop-based land use systems are more efficient in maintaining soil fertility than annual cropping systems. Certain tree crop plantations have remained productive for many decades, whereas homegardens have existed in the same place for centuries. However, cases of fertility decline under tree crops, including multistrata agroforestry systems, have also been reported, and research on the causal factors (both socioeconomic and biophysical) is needed. Plantation establishment is a critical phase, during which the tree crops require inputs but do not provide economic outputs. In larger plantations, tree crops are often established together with a leguminous cover crop, whereas in smallholder agriculture, the initial association with food crops and short-lived cash crops can have both socioeconomic and biological advantages. Fertilizers applied to, and financed by, such crops can help to `recapitalize' soil fertility and improve the development conditions of the young tree crops. Favorable effects on soil fertility and crop nutrition have been observed in associations of tree crops with N2-fixing legume trees, especially under N-deficient conditions. Depending on site conditions, the substitution of legume `service' trees with fast-growing timber trees may lead to problems of competition for nutrients and water, which may be alleviated through appropriate planting designs. The reduction of nutrient leaching and the recycling of subsoil nutrients are ways to increase the availability of nutrients in multistrata systems, and at the same time, reduce negative environmental impacts. These processes are optimized through fuller occupation of the soil volume by roots, allowing a limited amount of competition between associated species. The analysis of temporal and spatial patterns of water and nutrient availability within a system helps to optimize the use of soil resources, e.g., by showing where more plants can be added or fertilizer rates reduced. Important research topics in multistrata agroforestry include plantation establishment, plant arrangement and management for maximum complementarity of resource use in space and time, and the optimization of soil biological processes, such as soil organic matter build-up and the stabilization and improvement of soil structure by roots, fauna and microflora.

UNLABELLED: • PREMISE OF THE STUDY: Microsatellite loci were developed for tucuma of Amazonas (Astrocaryum aculeatum), and cross-species amplification was performed in six other Arecaceae, to investigate genetic diversity and population structure and to provide support for natural populations management. • METHODS AND RESULTS: Fourteen microsatellite loci were isolated from a microsatellite-enriched genomic library and used to characterize two wild populations of tucuma of Amazonas (Manaus and Manicore cities). The investigated loci displayed high polymorphism for both A. aculeatum populations, with a mean observed heterozygosity of 0.498. Amplification rates ranging from 50% to 93% were found for four Astrocaryum species and two additional species of Arecaceae. • CONCLUSIONS: The information derived from the microsatellite markers developed here provides significant gains in conserved allelic richness and supports the implementation of several molecular breeding strategies for the Amazonian tucuma.