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Item Phytosociology of weeds on Cerrado Mineiro coffee growing farms(Sociedade Brasileira da Ciência das Plantas Daninhas, 2022-09-30) Rodrigues, Rafael J. A.; Carvalho, Gladyston R.; Gonçalves, Adenilson H.; Carvalho, João Paulo F.; Alcântara, Elifas N. de; Resende, Laís S.Background Phytosociological surveys of weeds in agricultural regions, such as the coffee growing Cerrado Mineiro Denomination, are essential for understanding the predominant species in a cultivation area. Objective This study aimed to determine the predominant weed species in coffee crops in Cerrado Mineiro through phytosociological surveys during two periods of the year. Methods 26 coffee farms in 12 municipalities within the Cerrado Mineiro Denomination of Origin of were visited. The inventory square method was used for the phytosociological surveys. In each area, 40 m2 was evaluated and divided into two study periods (summer and winter). Calculations of the variables were performed using the following data: frequency, density, abundance, importance value index, similarity coefficient, rarefaction curve, Shannon index, and hierarchical grouping analysis using Jaccard’s similarity. Results In the summer (rainy period), 54 species from 16 families were found, with Poaceae, Asteraceae, and Amaranthaceae predominating. In winter (dry season), 56 species from 16 families were found, predominantly Asteraceae, Poaceae, and Brassicaceae. There was a predominance of 17 and 16 species, with similarity levels (Jaccard) of 45.58% and 40.78% for summer and winter, respectively. Conclusions The weed community in the Cerrado Mineiro coffee plantation is dominated by two main families, Poacaeae and Asteraceae, with Eleusine indica (summer) and Conyza spp. (winter) being the species with the highest importance values.Item Variability of photosynthetic performance among improved genotypes of Coffea canephora(Universidade Federal de Viçosa, 2025-05-09) Colodetti, Tafarel Victor; Tomaz, Marcelo Antonio; Rodrigues, Wagner Nunes; Christo, Bruno Fardim; Martins, Lima Deleon; Cavatte, Paulo CezarThis study evaluated the variability of photosynthetic performance of 27 improved genotypes of Conilon coffee, cultivated in the Southern of the Espírito Santo State. The photosynthetic performance was based on the measurement of gas exchange rates and chlorophyll in the period most favorable to the photosynthetic activity and in different stages of the reproductive cycle: flowering, fruit initiation, grain formation and fruit maturation; being expressed as the average (weighted by the number of days) along the phenological stages of the third reproductive cycle of the plants. It was possible to verify the existence of sufficient variability to differentiate the photosynthetic performance among the 27 genotypes throughout the reproductive cycle, even starting from a group of already improved genotypes. Among the physiological parameters, the rate of carbon assimilation, stomatal conductance and the transpiration rate stood out as parameters for the study of variability, mainly due to their contributions to the clustering of genotypes. The genotype 108 is highlighted due to its high photosynthetic rate, associated with higher relative content of chlorophyll, as well as reasonable water use efficiency. The genotypes 205, 206 and 305 stood out in terms of water use and carbon assimilation.Item Reproducibility of the RAPD marker and its efficiency in coffee tree genotype grouping analysis(Crop Breeding and Applied Biotechnology, 2002) Sakiyama, Ney Sussumu; Teixeira-Cabral, Terezinha Aparecida; Zambolim, Laércio; Pereira, Antonio Alves; Barros, Everaldo Gonçalves; Sakiyama, Cássia Camargo HargerThe genetic diversity of Coffea arabic L. cultivars is relatively narrow and its assessment and increase is important for breeding. Fifty two arbitrary primers were used to evaluate the reproducibility and the influence of the number of RAPD (Random Amplified Polymorphic DNA) markers on the estimation of genetic distances among 40 genotypes of Coffea spp. The average number of polymorphic bands was 6.69 per primer among all genotypes, and 1.27 among arabica coffee genotypes. RAPD markers were efficient in estimating the genetic distances among the genotypes. The increase in RAPD loci number during grouping analysis did not affect the major groups’ composition; however, it affected the composition of subgroups. Marker reproducibility was 76.88% and replicated data was recommended for distinguishing genotypes with the same genetic background.Item Adaptation to climate change in coffee production systems in Tolima(Instituto de Florestas da Universidade Federal Rural do Rio de Janeiro, 2019) Canal-Daza, Diana; Andrade-Castañeda, HernánIt was estimated the climate change adaptation of the main coffee production systems in Líbano, Tolima, Colombia, using diversity indicators. Three production systems were selected: agroforestry systems (AFS) with Cordia alliodora, AFS with plantain and in monoculture, with four replications, locating five sampling units to collect and identify the ant genera as diversity and adaptation indicators. The richness index of Margalef detected between systems (1.3 vs 0.6 vs 0.6 for AFS with C. alliodora, monoculure and AFS with plantain, respectively). The genera Cephalotes, Dorymyrmex, Hypoponera, Pachycondyla, Octostruma and Proceratium, which require abundant biomass and litter, were registered just in AFS with C. alliodora, coinciding with the depth of this layer. The AFS with C. alliodora present advantages due they improve conditions for the conservation of several groups of ants, which are indicators of diversity and climate change adaptation.Item Mirmecofauna asociada a cafetales bajo sombra en Quipile, Cundinamarca, Colombia(Universidad Nacional de Colombia, 2018) Gamba, Ricardo MartínezLa abundancia y variedad de microhábitats en los cultivos de café bajo sombra favorecen las poblaciones de hormigas. En cuatro fincas de la vereda Guadalupe alto del municipio de Quipile, Cundinamarca (Colombia) se determinaron la diversidad, la composición y los gremios de hormigas asociadas con el cultivo de café (Coffea arábiga) bajo sombra de Inga sp., Tabebuia rosea, Musa sp. y Citrus sp. Los muestreos se realizaron utilizando trampas de ‘caída y captura manual’ en épocas seca y de lluvia. En total, se registraron 82 morfoespecies distribuidas en 30 géneros y nueve subfamilias. Las eficiencias de muestreo variaron entre 78 y 82% con los estimadores CHAO2 e ICE; además, se encontró una baja similitud (< 60%) entre las fincas y entre los estratos suelo y tronco de árbol. Se identificaron especies exclusivas en las fincas como Heteroponera microps, Heteroponera inca, Odontomachus erytrocephalus y se registran por primera vez para Cundinamarca el género Proceratium y la especie Neoponera chyseri que incrementa la gran riqueza de especies de hormigas conocidas. Por otro lado, se encontró un total de nueve gremios presentes en todas las fincas del estudio y fueron reportados género como Azteca, Crematogaster, Linephitema, Pheidole y Solenopsis catalogados como potenciales controladores biológicos, lo que evidencia una forma de equilibrios ecosistémicos benéficos para el café bajo sombra en la zona.Item Hormigas asociadas a nectarios extraflorales de árboles de dos especies de Inga en cafetales de Cauca, Colombia(Universidad Nacional de Colombia, 2016) Sinisterra, Rosa Maria; Gallego-Ropero, María Cristina; Armbrecht, IngeEn dos fincas cafeteras localizadas en la vereda Villanueva, municipio de Popayán; Colombia, se identificó la comunidad de hormigas presentes en los nectarios extraflorales de árboles de guamo (Inga edulis e I. densiflora) utilizados como sombra en cafetales, y sobre la hojarasca del suelo. Las recolecciones se realizaron con cebos, extracción de hojarasca con sacos mini-Winkler y captura manual. Se encontraron 43 especies, distribuidas en 17 géneros y siete subfamilias. Los resultados mostraron que las especies de hormigas que habitan en los árboles son diferentes a las que habitan en la hojarasca, pero gracias a sus hábitos forrajeros algunas especies se desplazan de un estrato al otro. Se concluye que los árboles de sombrío como el guamo son importantes tanto para el mantenimiento de las interacciones mutualistas hormiga–planta, como para la conservación de la diversi dad; además, la presencia de árboles puede contribuir indirectamente a la prestación de servicios ecosistémicos fitosanitarios, ya que algunas especies de hormigas de los géneros Crematogaster y Camponotus pueden servir como potenciales agentes de control biológico para insectos plaga.