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The characterization and construction of genetic diversity panels provide valuable information for developing germplasm conservation strategies and applying advanced breeding techniques. Thus, we performed analysis of diversity and genetic structure in Cocos nucifera L. with a collection of dwarf and giant accessions belonging to the International Coconut Genebank for Latin America in the Caribbean. The collection comprises six dwarf accessions (represented by 36 individuals) and six giants (represented by 48 individuals). The analysis of clustering and DAPC performed from a set of 4,044 SNP markers showed the existence of three clusters, one of which was formed exclusively by all dwarf coconut accessions. The giant accessions were separated into two distinct clusters, one formed by accessions from regions bathed by the Pacific Ocean (Southeast Asia and Oceania) and another formed by accessions from regions bathed by the Atlantic Ocean (Brazilian coastline and West Africa). The analysis allowed us to observe that the cluster formed by the accessions of dwarf coconut is closer genetically to the cluster formed by the accessions of giant coconut from the Pacific than the others from the Atlantic. Both groups presented similar genetic diversity (GD) values, 0.25 and 0.26, respectively. The inbreeding coefficient (F) revealed the presence of greater heterozygosity than expected in the dwarf coconut accessions and the inbreeding in the giant accessions. Consequently, we provide important information for maintaining those accessions in the germplasm bank and for future implementation of genomic-wide association studies (GWAS) and genomic selection (GS) with the evaluated accessions.

Dwarf coconut tree is the main variety for commercial use in Brazil, which ranks fourth in world coconut production. However, the genotypes used still have limitations and genetic variability is required. The aim of this study was to estimate the genetic variability in dwarf coconut accessions preserved at the Germplasm Bank of Brazil at different harvesting times and using agronomic descriptors of plant and fruits. The accessions Brazilian Green Dwarf-Jiqui, Cameroon Red Dwarf, Malayan Red Dwarf, Brazilian Red Dwarf-Gramame, Brazilian Yellow Dwarf-Gramame, and Malayan Yellow Dwarf were assessed by means of 30 descriptors Variance analysis was performed and the genetic diversity was quantified by using the Mahalanobis’ generalized distance and expressed by means of UPGMA clusters, Tocher optimization, and canonical variables. The maximum likelihood analysis was used to estimate the components of variance with the data of each plant in a sample of 11 descriptors of great importance for the genetic improvement of the coconut tree. A phenotypic divergence was found among the accessions using the UPGMA clusters, Tocher optimization and graphic dispersion obtained with canonical variables. The use of the maximum likelihood analysis confirms the existence of genetic variability in the accessions for the descriptors fruit polar and equatorial diameter, nut polar diameter, total fruit weight, and epicarp thickness, which presented a heritability varying from 0.17 to 0.39. There is a possibility of genetic gains with the selection of these traits for use of accessions in breeding programs. O coqueiro anão é a principal variedade para uso comercial no Brasil, que ocupa atualmente a quarta posição na produção mundial. No entanto, os genótipos utilizados no país ainda apresentam limitações e há necessidade de variabilidade genética. Este trabalho teve por objetivo estimar a variabilidade genética em acessos de coqueiro-anão conservados no Banco de Germoplasma existente no Brasil, em diferentes épocas de colheita, utilizando descritores agronômicos de planta e frutos. Os acessos anão-verde-do-Brasil-de-Jiqui; anão-vermelho-de-Camarões; anão-vermelho-da-Malásia; anão-vermelho-de-Gramame; anão-amarelo-de-Gramame e anão-amarelo-da-Malásia foram avaliados por meio de 30 descritores. Análise de variância foi realizada e a diversidade genética foi quantificada utilizando a distância generalizada de Mahalanobis e expressa por meio de agrupamentos UPGMA, otimização de Tocher e variáveis canônicas. A análise de máxima verossimilhança foi utilizada para estimar os componentes de variância com os dados de cada planta em uma amostra de 11 descritores de maior importância para o melhoramento genético do coqueiro. Foi encontrada divergência fenotípica entre os acessos usando os agrupamentos UPGMA, Tocher e a dispersão gráfica obtida com variáveis canônicas. O emprego da análise de máxima verossimilhança confirma a existência de variabilidade genética nos acessos para os descritores diâmetro polar e equatorial do fruto, diâmetro polar da noz, peso total do fruto e espessura de epicarpo que apresentaram herdabilidade variando de 0,17 a 0,39. Há possibilidade de ganhos genéticos com a seleção desses caracteres para uso dos acessos em programas de melhoramento genético.

The dwarf coconut is widely used in the coconut hybrids production (tall × dwarf) because it presents higher precocity and higher productivity of the number of fruits in relation to the other varieties. However, these hybrids originated from Intervarietal crossing, produce fruits with low market acceptance for water quality. Intravarietal crosses (dwarf × dwarf) could act as an alternative, but little is known about the diversity within and between the dwarf sub-varieties, which can lead to a misdirection to breeding programs. In this study, we report the level of genetic variability between dwarf coconut accessions belonging to three sub-varieties (green, yellow and red), as well as the analysis of population structure. We used the RAD-sequencing methodology for analyzing 39 genotypes belonging to dwarf coconut populations collected in different producing regions of Brazil. Our results show that the SNP markers increased the power of detection of genetic variability, facilitating the decision making regarding future crosses in order to explore the heterosis in dwarf coconut breeding programs. Inter-sub-varietal crosses of dwarf coconut are highly promising to reduce the time and optimize the process of obtaining new cultivars for water production requiring field assessments to confirm its agronomic potential.

In the chemical and nutritional analyses of pumpkin, the size of bulk sample recommended by the method of reference, makes the process time consuming and difficult to execute. The purpose of the present study was to evaluate different sampling methods to indicate the most suitable one to replace reference method to determine the levels of total carotenoids, total soluble solids, and moisture in pumpkin. A completely randomized design was used with four treatments and 18 replications. The proposed methods consisted basically in changing the way of taking bulk samples from the fruits: cylinders method, quartile method, and the slice method. Samples obtained by proposed methods were analyzed for moisture content, total carotenoids and total soluble solids. Results obtained by each proposed method were compared against the method of reference. Cylinders method showed the best results and was the easiest to be carried out, consuming only about 1/10 of the time required in relation to the method of reference. The cylinder method was rapid, efficient, reliable and exhibited the greatest suitability for replacing the reference method.

A abobora (Cucurbita moschata Duch) e uma olericola de grande aceitacao em todo o Brasil, especialmente na regiao Nordeste. E bastante utilizada na alimentacao diaria do nordestino, onde e conhecida por Jerimum, para elaboracao de diversos pratos e doces, que podem ser caseiros ou industrializados. Durante o processo de coccao, ha perda de nutrientes e alteracao na qualidade do alimento a ser consumido. O trabalho foi desenvolvido com o objetivo de avaliar as alteracoes ocorridas em aboboras crioulas apos a coccao. Os 115 frutos avaliados foram oriundos do programa de melhoramento de abobora da Embrapa Tabuleiros Costeiros (CPATC), colhidos em outubro de 2013, no Campo Experimental Pedro Arle, localizado no municipio de Frei Paulo, Sergipe. As analises foram realizadas na Sala de Pos-colheita do CPATC, em Aracaju. Os pedacos, pesando cerca de 200g foram fervidos em 1L de agua, onde permaneceram por cinco minutos. Antes e apos a coccao, todas as amostras foram avaliadas quanto ao peso da massa fresca, firmeza e teor de solidos soluveis (SS). Foi realizado o teste de Tukey para comparacao de medias, ao nivel de 5% de significância, utilizando-se o programa estatistico SAS. Nao ocorreu perda de massa fresca significativa, que variou de 142,28g (antes) a 138,27 g (apos a coccao). Entretanto, o teor de SS diminuiu significativamente de 11,68 para 11,08oBrix, e a firmeza, de 12,75 a 5,69N. As caracteristicas avaliadas neste trabalho, associadas a outras de importância nutricional e comercial, sao importantes informacoes ao programa de melhoramento da especie.

Due to the great economic importance of coconut palm in Brazil and the development of a coconut breeding program intended to produce intravarietal hybrids, the present work aimed to ease the production of hybrids with the same morphological heritage. DNA was extracted from leaf samples of 13 dwarf coconut populations from Brazil, and PCR amplification was performed using 21 previously selected microsatellites. Furthermore, this study selected nine microsatellite markers with the potential to identify Green Dwarf x Yellow Dwarf hybrids and 16 microsatellites with the potential to identify Red Dwarf x Yellow Dwarf hybrids. In conclusion, SSR marker based on DNA Fingerprinting allowed the accurate identification of legitimate intravarietal hybrids since, for those crosses, the methodology of identification based on seedling color is not a viable alternative.

The tall coconut (Cocos nucifera L.) has great socioeconomic importance in Brazil and was first introduced on the coast of the north-eastern region, where it has been exploited in a semi-extractivist manner. The goal of this study was to quantify the genetic divergence between accessions introduced and preserved at the International Coconut Genebank for Latin America and the Caribbean, estimate the efficiency of descriptors used in the discrimination of the accessions, and indicate the essential descriptors for the activities of characterisation and evaluation. The accessions used were: Polynesia Tall; Tonga Tall; West African Tall; Rennel Tall; Rotuma Tall; Vanuatu Tall; Malayan Tall and Brazilian Tall Praia-do-Forte. Thirty-five quantitative descriptors recommended for the species were used. Genetic divergence was estimated by the Mahalanobis’s generalised distance and the cluster analysis was performed using the unweighted pair group method with arithmetic mean (UPGMA). The relative importance of the descriptors was measured according to Singh and Jolliffe’s methods, and the variables were selected taking into consideration the matching information in the two methods, eliminating those that were discarded in the two procedures. The agronomic characteristics indicated that the first canonical variable explained 90.25% of total variance. The most efficient descriptors for detecting the genetic divergence were: fruit equatorial circumference; nut polar and equatorial circumference; quantity of liquid endosperm; total fruit weight; nut weight; stem height; girth of stem at 1,5m height; number of leaflets; and number of bunches. The most dissimilar accessions according to the agronomic characteristics were Rotuma Tall and West African Tall, which can be primarily indicated as genitors for the formation of segregating populations in breeding programmes. RESUMO O coqueiro-gigante (Cocos nucifera L.) tem grande importância socioeconômica no Brasil e foi primeiramente introduzido no litoral da região Nordeste, onde é explorado de forma semi-extrativista. O objetivo desse trabalho foi quantificar a divergência genética entre os acessos introduzidos e conservados no Banco Internacional de Germoplasma de Coco para América Latina e Caribe, verificar a eficiência dos descritores utilizados na discriminação dos acessos e indicar os essenciais para etapas de caracterização e avaliação. Foram avaliados os acessos: Gigante-da-Polinésia; Gigante-de-Tonga; Gigante-do-Oeste-Africano; Gigante-de-Rennel; Gigante-de-Rotuma; Gigante-de-Vanuatu; Gigante-da-Malásia e Gigante-da-Praia-do-Forte. Utilizou-se 35 descritores quantitativos recomendados para a espécie. A divergência genética foi estimada pela distância generalizada de Mahalanobis e o agrupamento foi realizado pelo método UPGMA. A importância relativa dos descritores foi mensurada de acordo com os métodos de Singh e Jolliffe e as variáveis foram selecionadas levando-se em consideração as informações coincidentes nos dois métodos, eliminando-se aqueles que foram descartados em ambos os procedimentos. Utilizando as características agronômicas detectou-se que a primeira variável canônica explicou 90,25% da variância total. Os descritores mais eficientes para detecção da divergência genética foram: circunferência equatorial do fruto, circunferência polar e equatorial da noz, volume do endosperma, peso total do fruto e noz, altura de estipe, circunferência do estipe a 150 cm do solo, número de folíolos e número de cachos por planta. Os acessos mais dissimilares pelas características agronômicas foram o Gigante-de-Rotuma e Gigante-do-Oeste-Africano, os quais podem ser prioritariamente indicados como genitores para a formação de populações segregantes em programas de melhoramento.

Seed size and its physiology are a barrier for the exchange of coconut genetics resources and the tissue culture techniques can assist the germplasm bank enrichment. The aim of this study was to evaluate the effect of transport and storage procedures of zygotic embryos to promote the exchange of coconut accessions. Mature zygotic embryo from Cameroon red dwarf (CRD), Malayan yellow dwarf (MYD) and Malayan red dwarf (MRD) were used. The following treatments were evaluated: T1-storage of endosperm disc in plastic bags at 10±2°C for 5 days; T2 - 8 days; T3 - 12 days; T4 - embryo excised and inoculated in micro tube with Y3 culture medium with no sucrose for 2 days and T5 - five embryos inoculated in Y3 culture medium without sucrose in Petri dish for 2 days. T5 treatment resulted in low bacterial contamination. RESUMO: O tamanho da semente e sua fisiologia são barreiras para o intercambio de recursos genéticos de coqueiro e técnicas de cultura de tecidos podem auxiliar o enriquecimento de bancos de germoplasma. O objetivo deste estudo foi avaliar o efeito dos procedimentos de transporte e armazenamento de embriões zigóticos para o intercâmcio de acessos de coco. Foram utilizados embriões zigóticos maduros das variedades de coco anão vermelho dos Camarões (AVC), amarelo da Malásia (AAM) e vermelho da Malásia (AVM). Os seguintes tratamentos foram avaliados: T1- de armazenamento de disco endosperma em sacos de plástico a 10±2°C durante cinco dias; T2 - oito dias; T3 - doze dias; T4 - embrião inoculado em microtubo com meio Y3 sem sacarose por dois dias e; T5 - cinco embriões inoculados em placa de Petri com meio de cultura Y3 sem sacarose por dois dias. O tratamento T5 resultou em baixa contaminação bacteriana baixa.

O objetivo deste trabalho foi determinar a concentração de manitol para a germinação e crescimento mínimo in vitro do coqueiro (Cocos nucifera). Os seguintes acessos foram utilizados: Anão-vermelho-do brasil-de-gramame (BRDG), Anão-amarelo-da-malásia (MYD), Gigante-do-brasil-praia-do-forte (BRA), Gigante-da-polinésia (PYT) e Gigante-de-rennel (RIT). Os embriões foram colocados em meio de cultura Y3 a diferentes concentrações de manitol (0, 0,1, 0,2, 0,3 e 0,4 mol L-1). Verificou-se inibição do crescimento da parte aérea na presença de 0,1, 0,2 e 0,3 mol L-1, para MYD e BRDG, e de 0,1 e 0,2 mol L-1, para PYT, BRA e RIT. O uso do manitol é uma estratégia promissora para a conservação por crescimento mínimo.

Coconuts (Cocos nucifera L.) are tropical palm trees that are classified into Tall and Dwarf types based on height, and both types are diploid (2n = 2x = 32 chromosomes). The reproduction mode is autogamous for Dwarf types and allogamous for Tall types. One hypothesis for the origin of the Dwarf coconut suggests that it is a Tall variant that resulted from either mutation or inbreeding, and differences in genome size between the two types would support this hypothesis. In this study, we estimated the genome sizes of 14 coconut accessions (eight Tall and six Dwarf types) using flow cytometry. Nuclei were extracted from leaf discs and stained with propidium iodide, and Pisum sativum (2C = 9.07 pg DNA) was used as an internal standard. Histograms with good resolution and low coefficients of variation (2.5 to 3.2%) were obtained. The 2C DNA content ranged from 5.72 to 5.48 pg for Tall accessions and from 5.58 to 5.52 pg for Dwarf accessions. The mean genome sizes for Tall and Dwarf specimens were 5.59 and 5.55 pg, respectively. Among all accessions, Rennel Island Tall had the highest mean DNA content (5.72 pg), whereas West African Tall had the lowest (5.48 pg). The mean coconut genome size (2C = 5.57 pg, corresponding to 2723.73 Mbp/haploid set) was classified as small. Only small differences in genome size existed among the coconut accessions, suggesting that the Dwarf type did not evolve from the Tall type. Coconuts (Cocos nucifera L.) are tropical palm trees that are classified into Tall and Dwarf types based on height, and both types are diploid (2n = 2x = 32 chromosomes). The reproduction mode is autogamous for Dwarf types and allogamous for Tall types. One hypothesis for the origin of the Dwarf coconut suggests that it is a Tall variant that resulted from either mutation or inbreeding, and differences in genome size between the two types would support this hypothesis. In this study, we estimated the genome sizes of 14 coconut accessions (eight Tall and six Dwarf types) using flow cytometry. Nuclei were extracted from leaf discs and stained with propidium iodide, and Pisum sativum (2C = 9.07 pg DNA) was used as an internal standard. Histograms with good resolution and low coefficients of variation (2.5 to 3.2%) were obtained. The 2C DNA content ranged from 5.72 to 5.48 pg for Tall accessions and from 5.58 to 5.52 pg for Dwarf accessions. The mean genome sizes for Tall and Dwarf specimens were 5.59 and 5.55 pg, respectively. Among all accessions, Rennel Island Tall had the highest mean DNA content (5.72 pg), whereas West African Tall had the lowest (5.48 pg). The mean coconut genome size (2C = 5.57 pg, corresponding to 2723.73 Mbp/haploid set) was classified as small. Only small differences in genome size existed among the coconut accessions, suggesting that the Dwarf type did not evolve from the Tall type.

Landrace pumpkins occur in nature and their potential as source of pro-vitamin A may be investigated in order to be used in conventional plant breeding or biofortification programs, aiming to increase the total carotenoids and β-carotene contents. The objective of the study was to determine the total carotenoid, α-carotene, β-carotene and its isomers and contents in two landrace samples (A and B) of raw pumpkins (Cucurbita moschata) to verify its seed production potential. High Performance Liquid Chromatography and UV/Visible spectrophotometry were used to determine α-carotene, β-carotene and its isomers, and total carotenoid contents, respectively. All analyses were carried out in triplicate. The results showed mean total carotenoid contents of 404.98 in sample A, and 234.21 μg/g in sample B. The α-carotene contents varied from 67.06 to 72.99 μg/g in samples A and B, respectively. All E-β-carotene was the most abundant isomer found varying from 244.22 to 141.95 μg/g in samples A and B, respectively. The 9 and 13-Z-β-carotene isomers were still found in low concentrations in both analyzed landrace samples. The content of β-carotene in raw sample A showed to be promising for the production of seeds for cultivation and consumption.

The present work is a partial report for the introduction of eleven accessions of dwarf coconut and one accession of giant coconut tree into the International Coconut Genebank for Latin America and the Caribbean (ICG-LAC), a partnership between Embrapa Coastal Tablelands (CPATC) and Bioversity International, coordinated by Coconut Genetic Resources Network (COGENT). These accessions, originated from the International Coconut Genebank for Asia, India and Oceania (ICG-AIO), situated at Ivory Coast, were introduced in Brazil through zygotic embryos in November 2008. The mature fruits and endosperm cylinders with embryos were submitted at Ivory Coast to a phytosanitary treatment process according to international technical recommendations for safe movement of vegetal germplasm. At the Laboratory of Plant Tissue Culture of CPATC, the embryos were excised, surface sterilized and inoculated in Y3 culture medium. The first evaluation occurred after nine days of inoculation, and it was verified that 1.38% of the embryos were contaminated by fungi and 15.30% by bacteria. After 12 months of inoculation variation of in vitro development was observed within and among accessions and a high percentage of non-germinated and oxidated embryos. The normal germination percentage varied from 3.33% for ‘Niu Leka Dwarf’ to 33.3% for ‘Malayan Green Dwarf’ accessions. The non-germinated embryos percentage varied from 18.47% for ‘Tahitian Red Dwarf’ to 47.72% for ‘Sri Lanka Green Dwarf’ accessions. After 12 months, the contamination was higher for ‘Niu Leka Dwarf’ (70%). The percentage of non-germinated and oxidated embryos varied from 18.47% (‘Tahitian Red Dwarf’) to 47.72% (‘Sri Lanka Green Dwarf’). The great number of collected cylinders with exposed embryos (not protected by endosperm) and cracked endosperm, in addition to the long storage time (7 to 11 days) from collection to inoculation, favored bacterial proliferation. The non uniform stage of fruits/embryos maturation contributed to high variation of in vitro development.

Watermelon genetic resources used to set the watermelon breeding program at the Embrapa’s SemiArid Research Center are described as well as breeding objectives, program and methodologies. A germplasm flow chart shows the strategy used in the germplasm management of the Watermelon Germplasm Bank and in the breeding program. Selection for disease resistance and for plant and fruit characteristics of diploid and tetraploid lines are described and some relevant results are presented. Several diploid and triploid hybrid combinations, resistant to powdery mildew were evaluated. Some of these hybrid combinations presented good prospects as experimental hybrids to be tested in the field by farmers. New breeding tools to produce new generations of hybrids well adapted for the internal and external markets are discussed.

O trabalho foi conduzido na Estação Experimental, da Embrapa Semi - Árido, em Juazeiro (BA), de agosto a dezembro de 1993. Objetivou-se avaliar, por meio de técnicas de análise multivariada, o grau de similaridade genética entre 40 acessos de abóbora, coletados em três áreas distintas da região Nordeste. O delineamento experimental utilizado foi blocos ao acaso com três repetições e parcela útil composta por oito plantas. Avaliou-se o comprimento médio do internódio do pecíolo e do limbo; diâmetro médio do caule; largura média do limbo foliar; número médio de dias para antese da primeira flor masculina e da primeira flor feminina; localização do nó da primeira flor masculina e da primeira flor feminina; peso médio, comprimento, diâmetro maior e diâmetro menor do fruto, espessura do epicarpo e da polpa, diâmetro da cavidade interna do fruto; teor de sólidos solúveis, teor de matéria seca, número médio de sementes por fruto, comprimento médio de semente, peso médio de 100 sementes, número médio de sementes por grama. Os dados foram submetidos à análise por variáveis canônicas e análise de agrupamento pelo método de Tocher, adotando a distância generalizada de Mahalanobis (D²ii'). Verificou-se que 65% dos acessos formaram um único grupo. Os resultados das dispersões com base nas quatro primeiras variáveis canônicas (71% da variabilidade total) não possibilitaram um vínculo entre a divergência genética e a origem ecogeográfica dos acessos. Estes resultados mostraram-se concordantes com os obtidos pela técnica de agrupamento. Os caracteres mais importantes no tocante à variabilidade foram hierarquicamente: comprimento médio da semente, diâmetro maior do fruto, comprimento médio do fruto, nó de surgimento da primeira flor masculina, diâmetro médio do caule, número médio de dias para o aparecimento da primeira flor feminina, comprimento médio do internódio, peso médio do fruto, sólidos solúveis e número médio de sementes por grama. Os acessos B4, B5, P31 e P34 podem ser utilizados em programas de melhoramento que visem alto teor de sólidos solúveis (ao redor de 12,50%) e de matéria seca (acima de 15%) e frutos pequenos (inferior a 3 kg).

Avaliaram-se dezessete clones de capim-elefante (Pennisetum purpureum Schum.) num delineamento em blocos ao acaso, no esquema de parcelas subdivididas, com 4 repetições, de fevereiro de 1995 a dezembro de 1997, totalizando 12 cortes (medidas repetidas no tempo), no município de Campos dos Goytacazes, RJ. Objetivou-se obter estimativas de parâmetros genéticos e de coeficientes de repetibilidade das variáveis produção de matéria seca (PMS), altura média das plantas (ALT), diâmetro médio do colmo (DC) e número de perfilhos por metro linear (NP). Os valores de coeficiente de determinação genotípica (H2) variaram amplamente, desde 33,49% para PMS até 84,34% para ALT. Devem ser realizadas, pelo menos, nove, cinco, três e duas medições considerando as características PMS, ALT, DC e NP, respectivamente, para predizer o valor real dos genótipos, com base no coeficiente de determinação preestabelecido de 80%

O objetivo deste trabalho foi avaliar a adaptabilidade e a estabilidade da produtividade de grãos de 20 genótipos de feijão-caupi de porte semi-ereto, utilizando o modelo de efeitos aditivos principais e interação multiplicativa. Os ensaios foram conduzidos em 16 ambientes da Região Nordeste do Brasil. Os efeitos de genótipos, ambientes e da interação genótipo x ambiente, e os três primeiros eixos da análise de componentes principais (ACP) foram significativos. Os dois primeiros eixos da ACP explicaram juntos 55,11% da soma de quadrados da interação, correspondendo a 83,20% do padrão da interação genótipo x ambiente. As linhagens TE-97-321G-4, EVX-92-49E e EVX-63-10E apresentaram alta adaptabilidade, mas somente a última foi altamente previsível. A cultivar BRS Guariba e as linhagens EVX-92-49E e TE97-321G-4 expressam melhor potencial genético em ambientes de alta produtividade. The objective of this work was to evaluate the adaptability and the stability of the grain yield of 20 semierect cowpea genotypes, using the additive main effect and multiplicative interaction model. The trials were carried out in 16 environments of the Northeast Region of Brazil. The genotypes, environments and genotype x environment interaction, as well as the first three axes of the principal components analysis (PCA) were significant. The first two axes of the PCA explained 55.11% of the sum of squares of the genotype x environment interaction, corresponding to 83.20% of the pattern of genotype x environment interaction. TE97-321G-4, EVX-92-49E and EVX-63-10E lines were highly adaptable, but only the last one was highly predictable. BRS Guariba cultivar as well as EVX-92-49E and TE97-321G-4 lines best express their genetic potential in environments of high yield.

The aim of this study was to evaluate the storage potential of the pollen grains of Brazil Green Dwarf (BGD), Brazilian Tall (BRA) and Cameroon Red Dwarf (CRD) coconut accessions under different storage conditions. Representative plants of BGD, BRA and CRD accessions were selected from the Coconut Active Germplasm Bank of Embrapa Coastal Tablelands. The pollen grains were collected, placed in cryotubes and maintained under the following storage conditions: T1, refrigerator (-4°C); T2, freezer (-20°C); T3, ultra- freezer (- 80°C) and T4, liquid nitrogen (-196°C). The pollen grain viability was determined by staining with 1% acetic carmine and in vitro germination in a Lora culture medium at 30 and 60 days after the storage. Storage under refrigerator (-4°C), freezer (-80°C) and liquid nitrogen (-196°C) conditions promoted a better pollen grain viability of the Brazilian Tall coconut accession. Storage under freezer (-20°C) and liquid nitrogen (-196°C) conditions promoted a better pollen grain viability of the Cameroon Red Dwarf coconut accession. Storage under freezer (-20°C and -80°C) and liquid nitrogen (-196°C) conditions promoted a better pollen grain viability of the Brazil Green Dwarf coconut accession. The pollen grain viability of the Brazilian Tall coconut accession is stable after 30 and 60 days of storage.

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