Coffee Science_v.17, 2022
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Item Effect of flight operative height and genotypes on conilon coffee spraying using an unmanned aerial vehicle(Universidade Federal de Lavras, 2022-06-09) Vitória, Edney Leandro da; Oliveira, Ronaldo Furtado de; Crause, Deborah Hoffmam; Ribeiro, Luis Felipe OliveiraThis study analyzed the effect of operational flight height and conilon coffee genotypes in the deposition and uniformity of destruction in the plant’s can-opy. The spray were conducted using a unmanned aerial vehicle in a conilon coffee plantation. The experiment was carried out with a randomized block design and treatments arranged in a factorial scheme, with three operational flight heights in relation to the coffee canopy and three genotypes of conilon coffee (Coffea canephora). The parameters evaluated were volume median diameter (VMD), density of drops and coverage (%). The interaction between flight height variables and canopy’s range was significant for the data on VMD variables, droplet density and coverage. According to the results, spray performance at an average height of 3.0 m is better than at 2.0 and 4.0 m. At 4.0 m, we observed a decrease in these variables, and this can be explained by a possible drift caused by the wind intensity and direction at higher heights. The coverage on the genotype A1 leaves was higher when compared to the other genotypes, although flight operational height was significantly different only in this genotype, 8.1% at 4.0 m, we observed at this height the lowest coverage values.Item Identifying Coffea genotypes tolerant to water deficit(Universidade Federal de Lavras, 2022-06-09) Molina, Diana; Rivera, Ruben MedinaApproximately 26% of the coffee grown in Colombia is located in areas presenting water deficit, with some of these areas also presenting high solar brightness. This combination reduces coffee production, thus affecting the income of 31% of the country’s coffee-growing families. To identify accessions of the Colombian Coffee Collection (CCC) that are tolerant to water deficit, 65 genotypes were evaluated in screenhouse conditions at the National Coffee Research Center (Cenicafé), located in Manizales, Caldas, Colombia. Seedlings of each genotype were transplanted to polyethylene bags, each filled with 10 kg sandy loam Andisol soil. Two moisture treatments were applied as follows: (1) soil at field capacity (60% moisture) and (2) water deficit conditions, with soil at 50% field capacity (30% moisture). After five months, total dry biomass was determined, considered as the sum of the dry biomass of leaves, stems, and roots. The Student’s t test for independent samples was used to analyze resulting values at a level of significance of 5%. Reducing irrigation under water deficit conditions usually delays accession growth, which is reflected in decreased biomass. However, the total dry biomass of nine Ethiopian introductions of Coffea arabica (CCC238, CCC254, CCC284, CCC372, CCC474, CCC536, CCC537, CCC555, CCC1147), six diploid accessions (CCC1030, EA.20, EA.209, EA.227, EA.229, EA.287), and three interspecific hybrids of Caturra x Coffea canephora (25, 640, 702) in water deficit conditions did not differ sta-tistically from the total dry biomass obtained in treatments with irrigation at field capacity. Because these introductions present adaptation mechanisms to water deficit, they retain their leaves without reducing their leaf area or total dry biomass and should accordingly be considered as candidates for evaluation in dry regions to determine their tolerance to water deficit based on effects on production or biomass.Item Genetic variability of conilon coffee population from cultivar ‘ES8152’ based on morphoagronomic variables(Universidade Federal de Lavras, 2022-06-09) Senra, João Felipe de Brites; Silva, Josimar Aleixo da; Ferrão, Maria Amélia Gava; Esposti, Marlon Dutra Degli; Milheiros, Idalina Sturião; Fassarella, Kamila MachadoThis study aimed to analyze the genetic variability of Coffea canephora population with 190 genotypes from cultivar ‘ES8152’, based on morphoagronomic characteristics and vegetation index, to identify the most important characteristics for genetic divergence and compare them with commercial clones. The experiment was installed, in 2019, at the Bananal do Norte Experimental Farm/INCAPER, Cachoeiro de Itapemirim, ES, Brazil. The experiment was carried out in Federer’s augmented block design with three blocks, four common treatments (commercial clones A1, LB1, V8 and V12) and 190 regular treatments, genotypes from the seed production field of the conilon coffee cultivar ‘ES8152’. At 24 months of age 14 morphoagronomic characteristics and vegetation index were evaluated. Descriptive analysis of the data, the estimation of the Standardized Euclidean Distance (ED) followed by the group-ing by the methods of Tocher, UPGMA and principal coordinates, in addition to the relative importance of the characters estimated by the Singh meth-odology were performed. The most distant genotypes were 62 and 83 (ED=2.620) and the closest were 42 and 160 (ED=0.208). Genotype 83 stood out as the most distant among the others. The optimization and hierarchical groupings allowed the identification of genotypes 15, 81, 107 and 184 as similar to commercial clones. The discard analysis of variables recommended the elimination of the vegetation index and average internode length of the next diversity analysis. Principal coordinate analysis found phenotypic similarity of the genotypes 30, 81, 115, 141 and 163 with the clone V12, of the genotype 119 with the clone A1 and genotype 17 with clone LB1. The study, of morphoagronomic characters, allowed to detection the genetic diversity existing in the materials evaluated, indicating those with phenotypic similarity with the commercial clones, being possible the early identification of promising genotypes, agronomically superior, to start a breeding program for clonal selection, recurrent selection and controlled crosses to maximize heterosis.