Firmino José do Nascimento Filho

Divergência genética entre clones de guaranazeiro

As tecnicas multivariadas, para estimar a diversidade genetica de um grupo de progenitores, tem sido utilizadas com frequencia pelos melhoristas de plantas. Os progenitores sao utilizados em cruzamentos biparentais ou multiplos, para formacao de populacoes segregantes que tenham maior probabilidade de recuperacao de genotipos superiores. Este trabalho foi realizado com o objetivo de identificar clones de guaranazeiro produtivos e divergentes que possam ser utilizados em um programa de cruzamentos para obter hibridos com alto valor heterotico e materiais para propagacao vegetativa. Foram avaliados 148 clones de guaranazeiro atualmente em uso no programa de melhoramento genetico da Embrapa-Centro de Pesquisa Agroflorestal da Amazonia Ocidental. Utilizou-se, para estimativa da divergencia genetica, a analise de agrupamento, em que a medida de dissimilaridade utilizada foi a distância euclidiana media padronizada e os metodos de agrupamento de otimizacao de Tocher e do vizinho mais proximo para construcao do dendrograma entre grupos de clones. Houve a formacao de sete grupos divergentes de clones. Concluiu-se que a divergencia genetica entre os clones nao e grande, pois dois grupos foram formados com dois clones e tres grupos foram formados somente com um unico clone. Os clones CMU384 e CMU801 foram os mais proximos geneticamente e podem ser utilizados na formacao de uma populacao com desenvolvimento vegetativo uniforme para uso em plantios comerciais.

Repetibilidade da produção de sementes em clones de guaraná

The aim of this work was to evaluate the seed yield repeatability of 27 guarana clones. Ten assays were carried out for clone evaluation using a completely randomized block design, with two replicates and three plants per plot with a 5x5 m spacing. The seed yield was measured during four years (1998, 1999, 2000 and 2001) after the beginning of the production phase, two years after planting. Four methods were used for repeatability coefficient estimation: analysis of variance (ANOVA), principal components analysis based on correlation matrix (CPCOR), principal components analysis based on phenotypical variance and covariance matrix (CPCOV), and structural analysis based on correlation matrix (AECOR). Minimum observations number and determination coefficient were also evaluated. The repeatability coefficient estimates based on these four years, in all ten environments, were relatively low - 0.2618 (AECOR), 0.3064 (CPCOR), 0.3183 (ANOVA) and 0.5308 (CPCOV) - and varied according to method and environment. At least four years of evaluation are necessary for obtaining the real genotypical value of the clones for an 80% determination coefficient.

Adaptabilidade e estabilidade de clones de guaraná

The objective of this work was to determine parameters of adaptability and phenotypic stability of guarana clones (Paullinia cupana) in the state of Amazonas, Brazil. Ten trials were carried out in three counties, where 27 preselected guarana clones were evaluated in a four-year period. A randomized complete block design with two replicates were used, with plots formed by three plants spaced at 5x5 m. Four methods of adaptability and stability were evaluated. The nonparametric method of Lin & Binns modified showed satisfactory results and discriminated the clones performance both in favorable and unfavorable environments, and according to their stability levels. The CMU871 had good adaptability and high phenotypic stability. The CMU619 and CMU609 had specific adaptability to favorable and unfavorable environments, respectively.

Enraizamento de estacas de cultivares de guaranazeiro com adubação de plantas matrizes

The objective of this work was to evaluate the effect of plant fertilization on the rooting of guarana cuttings. The experimental design was completely randomized in a 6x2 factorial arrangement, with five cultivars and one genotype of guarana, with or without fertilization. The experimental unit contained ten cuttings with four replicates. The fertilization was applied after pruning (January), after fruiting (April), and before the beginning of flowering (May). For rooting, the cuttings were kept in incubators at 50% irradiance and under intermittent mist. After 120 days in the incubator, the following characteristics were evaluated: rooted and dead cuttings; cutting length; and volume and dry weight of roots. Plant fertilization increased rooting in 11.15%, and reduced cutting mortality in 11.05%. The fertilization promoted a greater rooting in the cultivars BRS-Maues, BRS-CG882 and in the genotype CMU 381. Irrespective of the cultivar, the fertilization increases the number, volume and weight of root dry matter; however, it has no influence on root length.

Guarana—Paullinia cupana Kunth var. sorbilis (Mart.) Ducke

Abstract Guarana (Paullinia cupana Kunth var. sorbilis (Mart.) Ducke, Sapindaceae) is a native Brazilian species of considerable economic and social importance; it is a rainforest perennial climbing shrub that was domesticated in the Amazon due to its caffeine-rich seeds. Brazil is the only producer of guarana in the world, satisfying both domestic and international demand. Over the last few decades, the area planted with guarana has expanded beyond Amazonia and guarana is now planted in the states of Amazonas, Acre, Para, Rondonia, Bahia, and Mato Grosso. The guarana breeding program coordinate by Embrapa Western Amazon (Embrapa’s Western Amazonia unit) began in 1976 and after almost 39 years of very successful research, released 19 clonal cultivars between 1999 and 2015. The objective of this chapter is to summarize current knowledge and advances on the guarana breeding program.

Associação entre características da parte aérea e do sistema radicular em mudas de guaranazeiro por correlações canônicas

This study aimed to quantify the degree of association between variables of shoots and roots system of seedlings cloned from guarana, using canonical correlations, in order to improve the procedure of selection of seedlings to ensure increased survival percentage of seedlings after planting. Two groups of variables suitable for final planting seedlings in 36 guarana clones. The experimental design was a randomized complete block with five replications and 10 plants per plot, under nursery conditions. We used the canonical correlation analysis. The group of variables of shoot is not independent of variable group of root system. Through selection based on variables from the air, you can improve the root system, mainly through the greater length of the branch (CRA). Can practice the selection of clones of guarana for increased root weight without the need to destroy the seedlings carrying only measurements of the length of the branches.

Produção e distribuição de fitomassa no guaranazeiro (Paullinia cupana H.B.K. var. sorbilis (Mart.) Ducke)

Apesar da importância economica do guaranazeiro (Paullinia cupana H.B.K. var. sorbilis (Mart.) Ducke) em algumas regioes do Brasil, existem poucas informacoes sobre sua caracterizacao fenologica. Assim, realizou-se um estudo cujo objetivo foi de quantificar a producao de fitomassa e sua distribuicao, em uma populacao de guaranazeiros, originadas de propagacao sexuada. Foram avaliadas cinco plantas adultas, que lancaram mais de 100 ramos por planta ano-1, dos quais apenas 50 % produziram frutos. As plantas lancaram entre 445 e 1294 inflorescencias por ano, porem, de 67 % a 98 % produziram apenas um fruto. A producao de materia seca total foi estimada em 15,8 kg por planta ao ano, o que corresponde 6350 kg ha ano-1. Nas plantas, o maior acumulo de materia seca apresentou a seguinte ordem: folhas>ramos>sementes>raquis>casca dos frutos+arilo> peciolos.

Fertilization and cover crop effects on soil nitrogen and plant nutrition in a young guarana plantation

Fruit tree production is gaining an increasing importance in the central Amazon and elsewhere in the humid tropics, but very little is known about the nutrient dynamics in the soil-plant system. The present study quantified the effects of fertilization and cover cropping with a legume (Pueraria phaseoloides (Roxb.) Benth.) on soil nitrogen (N) dynamics and plant nutrition in a young guarana plantation (Paullinia cupana Kunth. (H.B. and K.) var. sorbilis (Mart.) Ducke) on a highly weathered Xanthic Ferralsol. Large subsoil nitrate (NO3-) accumulation at 0.3-3 m below the guarana plantation indicated N leaching from the topsoil. The NO3- contents to a depth of 2 m were 2.4 times greater between the trees than underneath unfertilized trees (P 0.05). Even without a legume intercrop, large amounts of NO3- were found in the subsoil between unfertilized trees. Subsoil NO3- between the trees could be utilized, however, by fertilized guarana. This can be explained by a more vigorous growth of fertilized trees which had a larger nutrient demand and exploited a larger soil volume. With a legume cover crop, however, more mineral N was available at the topsoil which was leached into the subsoil and consequently accumulated at 0.3-3 m depth. Fertilizer additions of P and K were needed to increase subsoil NO3- use between trees.