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Local varieties of cowpea are promising for breeding programs, as they harbor an important source of genetic variability. The objective of this study was to estimate the genetic variability among cowpea genotypes based on morphological and agronomic descriptors. The experiment was carried out in a randomized complete block design with three replications in the experimental field at Universidade Federal do Acre, in Rio Branco, Acre, Brazil. The experimental unit consisted of six lines of 5.0 m, with a spacing of 0.80 m x 0.50 m, with the four central lines used in the evaluations of 21 characters. The treatments consisted of seven local cowpea genotypes. The Mahalanobis generalized distances (D2) were calculated and used in the Tocher and UPGMA clusters. Principal component analysis, relative contribution of traits and analysis of variance were also performed. Manteiguinha and Mudubim de Rama were the most dissimilar genotypes, while Ceará Mercado and Baiano were the most similar. The main component of greater explanation illustrated the separation of genotypes into two groups, with the union between Manteiguinha and Manteigão forming one group and the other genotypes forming the other group. The traits grain yield, number of grains per pod and grain mass of fifty pods were the main determinants in the quantification of genetic divergence. The combination of the Manteiguinha with Mudubim de Rama genotypes is the most suitable for obtaining promising segregating populations.

The use of agricultural residues for the production of alternative substrate is essential to reduce seedling production costs, as well as to reduce the environmental impacts resulting from the use of commercial substrates. Thus, the objective of this study was to evaluate the morphological and physiological performance of Passiflora edulis fruit seedlings as a function of alternative Theobroma grandiflorum bark substrates. The experiment was carried out in a screened nursery with sombrite of 50%, with a randomized block design with three replications and five plants per plot. The treatments consisted of the combination of ground and crushed cupuaçu bark in percentages of 20%, 40%, 60% and 80%. Liquid photosynthesis, stomatal conductance, internal CO2 concentration, transpiration, plant height, stem diameter, main root length, number of leaves, dry and fresh shoot and root weight and Dickson Quality Index were evaluated. The morphological and physiological performance of passion fruit plants was influenced by the cupuaçu bark concentration. Substrates containing 20 to 40% cupuaçu bark resulted in better seedlings, as they promoted increased net photosynthesis, gas exchange, leaf number, higher root growth and development, and larger stem diameter and shoot height. Consequently, the Dickson quality index showed excellent values, which shows an improvement in the biometric and physiological characteristics of the passion fruit seedlings produced with substrates based on cupuaçu bark.

Increasing corn grain production without devastating new forest areas is a viable alternative to controlling deforestation. However, increasing plant density in the area may alter plant morphophysiological and productive traits. The objective of this study was to characterize relationships between physiological, morphological and yield traits of corn plants, as well as the cause, effect and relationship of the traits on grain yield. The experiment was carried out in randomized complete block design with four replications. The corn hybrids (2B655PW, AG7088PRO3 and P4285YHR) were grown with row spacing of 40 cm, 60 cm, 80 cm, 95 cm. The evaluated traits physiological were: net photosynthesis (PN), stomatal conductance (Gs), intercellular concentration of CO2 (Ci), leaf transpiration (E), water use efficiency (WUE) and carboxylation efficiency (CE). The morphological were: plant height (PH) and ear insertion height (EIH), stem diameter (SD), and leaf area (LA) and the productive traits were the total number of ear per hectare (NE), number of grains per ear (NGE), grain mass per ear (GME), 100 grain weight (100GW) and grain yield (GY). The characteristics of maize hybrids cultivated in environment with reduced spacing (40cm, 60cm, 80cm, 95cm) of the 2016/2017 crop were investigated through the multicollinearity path analysis. The physiological, morphological and productive traits are considered sources of variation of cause and effect of corn yield in reduced spaced. This traits are essential for observations in maize breeding programs to obtain high yielding varieties in reduced spacing. In conclusion, the physiological (PN, CE, WUE, Ci, Gs), morphological (EIH, SD, LA) and productive (NE, GME) traits provide gains in maize grain yield via indirect selection when the crop is subjected to 40 cm row spacing.

Muitos processos que estruturam o solo são realizados por invertebrados edáficos, sendo os insetos o principal grupo. A ordem Coleoptera é a maior dentro da classe Insecta, tendo a família Scarabaeidae uma das mais representativas e importantes. O objetivo deste trabalho foi conhecer a fauna de Scarabaeidae edáficos em um remanescente florestal no município de Plácido de Castro, AC. O estudo foi realizado entre agosto de 2014 a agosto de 2015, utilizando 22 armadilhas pitfalls (copos plásticos de 500 mL) dispostas em dois transectos, distanciadas cinco metros entre si, com espaçamento de 10 m entre armadilhas. Em cada armadilha foi adicionada uma solução de formaldeído (1%) e gotas de detergente neutro, com coletas quinzenais. No laboratório de Entomologia da Embrapa Acre os insetos foram triados e identificados com auxílio de literatura apropriada. Foram capturados 218 espécimes, representados por quatro tribos, sete gêneros e 15 espécies. A tribo Coprini foi a mais representativa, com nove espécies capturadas, sendo sete correspondendo ao gênero Canthidium. Pelo número de espécies capturadas e nichos alimentares conclui-se que o remanescente florestal estudado apresenta baixo grau de antropização. Many processes that structure the soil are carried out by edaphic invertebrates, with insects being the main group. The order Coleoptera is the largest within the class Insecta, with the family Scarabaeidae one of the most representative and important. The aim of this work was to know the edaphic fauna of Scarabaeidae in a forest remnant in the municipality of Plácido de Castro, Acre state, Brazil. The study was realized between August 2014 to August 2015, using 22 pitfall traps (500 mL plastic cups) arranged in two transects, five meters apart, with 10 m spacing between traps. In each trap was added a solution of formaldehyde (1%) and neutral detergent drops, with biweekly samplings. In the Embrapa Acre?s Entomology Laboratory the insects were tried and identified with the aid of appropriate literature. Twenty-one specimens, represented by four tribes, seven genera and 15 species were captured. The Coprini tribe was the most representative, with nine species captured, of which seven corresponded to the genus Canthidium. By the number of species captured and food niches, it can be concluded that the studied forest remnant presents a low degree of anthropization. Made available in DSpace on 2020-01-03T18:16:51Z (GMT). No. of bitstreams: 1 26940.pdf: 73011 bytes, checksum: da87b5f96b4ded24b51ec2c18b83d8bb (MD5) Previous issue date: 2019

A seringueira (Hevea brasiliensis) é uma planta popularmente conhecida por ser a principal fonte de borracha natural. Assim, é fundamental que este recurso genético esteja devidamente avaliado e caracterizado. O objetivo desse trabalho foi caracterizar por meio de marcadores microssatélites a diversidade genética de acessos do banco de germoplasma de seringueira da Embrapa Amazônia Ocidental, Embrapa Amazônia Oriental e Embrapa Cerrados. Foram amostrados 318 acessos, pertencentes às espécies Hevea brasiliensis, Hevea pauciflora, Hevea rigidifolia e híbridos interespecíficos. Foram testados 10 marcadores microssatélites. Os produtos amplificados foram genotipados em sequenciador automático. As estimativas genéticas estimadas foram: heterozigosidade esperada (HE) e observada (HO), número de alelos por loco e conteúdo de informação polimórfica (PIC). Os dados genéticos foram utilizados para verificar a estruturação dos genótipos, agrupamento pelo método de Neighbor-Joining, dispersão por coordenadas principais e formação de uma coleção nuclear. Os dez locos microssatélites revelaram 348 alelos. As médias de HE, HO e PIC foram de 0,86, 0,63 e 0,86, respectivamente. Os marcadores microssatélites de H. brasiliensis foram potencialmente transferíveis para H. pauciflora e H. rigidifolia. As distâncias genéticas entre o acesso de Hevea spp. variaram de 0,16 a 0,94. A coleção nuclear formada por 59 genótipos representou 85% da diversidade alélica total. Conclui-se que o polimorfismo foi alto entre os genótipos avaliados. As espécies de Hevea compartilham homologias em regiões flanqueadoras de microssatélites. As distâncias genéticas demonstraram alta variabilidade entre os acessos amostrados. A coleção nuclear constituiu-se de 19% do número total de acessos. The rubber tree (Hevea brasiliensis) is a plant popularly known for being the main source of natural rubber. It is therefore essential that this genetic resource is properly evaluated and characterized. The objective of this work was to evaluate by microsatellite markers the genetic diversity of accesses of the rubber germplasm bank of Embrapa Amazônia Ocidental, Embrapa Amazonia Oriental and Embrapa Cerrados. It was used 318 accessions, belonging to the species Hevea brasiliensis, Hevea pauciflora, Hevea rigidifolia and interspecific hybrids. Ten microsatellite markers were tested. The amplified products were genotyped in an automated sequencer. The estimated genetic estimates were: expected heterozygosity (HE) and observed (HO), number of alleles per locus and content of polymorphic information (PIC). Genetic data were used to verify the structure of the genotypes, grouping by the Neighbor-Joining method, dispersion by main coordinates and formation of a nuclear collection. The ten microsatellite loci revealed 348 alleles. The mean values of HE, HO and PIC were 0.86, 0.63 and 0.86, respectively. The microsatellites markers of H. brasiliensis were potentially transferable to H. pauciflora and H. rigidifolia. The genetic distances between the access of Hevea spp. ranged from 0.16 to 0.94. The nuclear collection of 59 genotypes represented 85% of the total allelic diversity. It was concluded that the polymorphism was high among the evaluated genotypes. Hevea species share homologies in microsatellite flanking regions. The genetic distances showed high variability among the accessions sampled. The nuclear collection constituted 19% of the total number of accesses. Made available in DSpace on 2018-05-04T00:44:48Z (GMT). No. of bitstreams: 1 26609.pdf: 3467420 bytes, checksum: 619510684dc554ee866323762f71e4b8 (MD5) Previous issue date: 2018-05-03 Dissertação (Mestrado em Ciências e Inovação Tecnológica) - Programa de Pós-graduação em Ciência, Inovação e Tecnologia para a Amazônia, Universidade Federal do Acre, Rio Branco. Orientador: Tatiana de Campos.