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Item Comparison of fructification efficiency between reciprocal crosses in Coffea canephora(Universidad Nacional de Colombia, 2023-10-09) Ferrão, Maria Amélia Gava; Fonseca, Aymbiré Francisco Almeida da; Ferrão, Romário Gava; Volpi, Paulo Sérgio; Verdin Filho, Abrão Carlos; Rocha, Rodrigo Barros; Riva-Souza, Elaine ManelliThis study aimed to assess and compare the behavior of superior genotypes of Coffea canephora in terms of fruiting capacity using directed hybridizations in a full diallel design with reciprocals.Hybridizations were performed using 12 possible combinations between genotypes 02, 03, 23 and 83 from the Incaper breeding program. High estimates of the genotypic coefficient of determination in terms of the total number of pinheads per cross (TNP) and fruit set (FS) indicated variability of genetic nature. FS averaged 52,27%, ranging from 31,32% to 82,09%, with the higher rates relating to clone 23 as the male parent. Differences were found between reciprocal crosses in the combinations with genotype 23, which emerged as the donor plant with the best fruiting rate, but poor receiving ability. Clone 83 prevailed as the best receiving plant and the least effective donor. In the comparison of these two genotypes, antagonism was observed in their behavior when they were used as pollen-donor plants (male parents) and pollen-receiver plants (female parents), highlighting their possible maternal effect. Crosses involving clones 02 and 03 showed no differences when used reciprocally. The estimates of genotypic correlations were negative for the four associations involving the FS characteristic, being of greater magnitude with TNP.Item Grain yield of coffee plants fertilized with different doses of 20-00-20 NPK formulation under rainfed conditions(Universidade Federal Rural do Semi-Árido, 2021-07-12) Torres, Josemar Dávila; Espindula, Marcelo Curitiba; Araújo, Larissa Fatarelli Bento De; Marcolan, Alaerto Luiz; Rocha, Rodrigo BarrosLittle is known about the management of high-yield clonal Coffea canephora in the Amazonian Region, mainly for nutritional aspects and cultivation system efficiency. This study aimed to evaluate the influence of different nitrogen and potassium fertilization rates on coffee grain yield and fertilizer use efficiency of C. canephora trees. An experiment was performed at an experimental field of the Embrapa Rondônia in Porto Velho (RO), Brazil. It was carried out in a split-plot scheme with six doses of 20-00-20 NPK formulation (0; 250; 500; 1,000; 2,000; and 3,000 kg ha-1) and three years of evaluation (2014, 2015, and 2016). An interaction between fertilizer dose and crop year was observed. Fertilizer doses showed an exponential behavior, with maximum yields of 51, 114, and 79 bags ha-1 at 3,000 kg ha-1 in the crop years of 2014, 2015, and 2016, respectively. Such a behavior impacted average and accumulated yields in the three harvest seasons. As for crop year effect within each fertilizer dose, the highest yield was reached in the second harvest after pruning for renewal of orthotropic stems. Moreover, fertilizer use efficiency by plants decreased exponentially, with the highest value at the lowest dose. Increasing doses of 20-00-20 formulation promoted an exponential increase in grain yield but decreased its use efficiency by C. canephora plants. This management also stimulated a strong biannual production.Item In vitro pollination and fluorescence microscopy for characterization of gametophytic selfincompatibility of Coffea canephora Pierre ex A. Froehner(Crop Breeding and Applied Biotechnology, 2021-11-20) Souza, Carolina Augusto de; Rocha, Rodrigo Barros; Santos, Maurício Reginaldo Alves dos; Lopes, Tatiane Almeida; Teixeira, Alexsandro Lara; Espindula, Marcelo CuritibaThe objectives of this study were to optimize in vitro pollination and fluorescence microscopy procedures to characterize the gametophytic selfincompatibility of Coffea canephora genotypes. For that purpose, 115 in vitro pollinations were carried out among 30 parent plants of the Conilon (17) and Robusta (13) botanical varieties. Tester plants of compatibility groups I, II, and III were used as pollen grain donors. On the day of anthesis, pollen grains of the donor genotypes were transferred in vitro to one of the sides of the bifid stigma of each receptor flower. After 30 hours, the development of the pollen tubes was evaluated in fluorescence microscopy. Eleven genotypes (37%) were classified in compatibility Group I, thirteen (43%) in Group II, and six (20%) in Group III. In vitro pollination allowed reduction in the time necessary to diagnose compatibility, without exhibiting contamination caused by the presence of pollen grains of non-donor plants.Item Evaluation of a prototype of soil thermal solarizer for control of gall nematode in the production of coffee seedlings(Universidade Federal de Lavras, 2023-02-23) Uchôa, Francisco Paiva; Vieira Junior, José Roberto; Fernandes, Cléberson de Freitas; Rocha, Rodrigo Barros; Espíndula, Marcelo Curitiba; Rudnick, Vaneide Araújo de Sousa; Silva, Dvany Mamedes da; Freire, Tamiris Chaves; Sangi, Simone Carvalho; Mariobo, Solange Aparecida RodriguesIn coffee crops at Rondônia State of Brazil, there is an increase in phytonematode epidemics.Since most local coffe nurseries at Rondônia use soil as substrate for seedling production, this work aimed to test the minimum exposure time at 60 ºC to control of root-knot nematodes Meloidogyne incognita in soil by means of solar heating, using a solarizer, in an adapted version for better heating perfomance. The used solarizer prototype was built of a wooden box covered with metal sheets, thermal blankets, painted black, with aluminum pipes of 0.5 cm in diameter at the bottom of the box that circulates the water heated by the collector box. The soil was inoculated with a suspension of 1000 eggs + J2 of M. incognita per liter and placed in equipment with a capacity of 150 liters. Exposure times at a minimum temperature of 60 °C were evaluated, with 14 treatments: C1 (non-inoculated and not autoclaved), C2 (inoculated), C3 (non-inoculated and autoclaved) T0’, T15’, T30’, T45’, T60’, T180’, T360’, T720’, T1440’, T2880’ and T4320’ . The temperature was measured every 15 minutes using a skewer-type digital thermometer. The soil was removed according to the exposure time, and placed in 8-liter pots, in which clone 125 and BRS 2357 coffee seedlings, susceptible to M. incognita , were transplanted and growing in a greenhouse for 180 days. The experimental design used was DIC, with 6 replications, each seedling as na experimental unit. Reproduction factor (FR), number of eggs per plant (NOGR) and number of galls per gram of root (NGGR) were evaluated. The FR, NOGR and NGGR variables reduced with exposure time. All treatments showed an effect to control the population of M. incognita in infected soils, with 100% efficacy of pathogen eradication from the T45’ treatment, 60 minutes of exposure is recommended for the production of Coffea canephora seedlings. Taken together, thir work showed the high potential of thr solorizer to contribute in the root-knot nematode control to seedling production.Item Resistance of Coffea canephora as a sustainable tool for Meloidogyne incognita control(Universidade Federal de Lavras, 2022-12-29) Silva, Dvany Mamedes da; Vieira Júnior, José Roberto; Rocha, Rodrigo Barros; Espindula, Marcelo Curitiba; Rudnick, Vaneide Araújo de Sousa; Fernandes, Cléberson de Freitas; Uchôa, Francisco Paiva; Bastos, Jéssica Silva Felix; Freire, Tamiris Chaves; Sangi, Simone Carvalho; Fonseca, Aline Souza daMany factors can affect coffee production, such as the root-knot nematode, a soil pathogen that can kill plants up to two years old. In infested areas, the cultivation of resistant genotypes is an economical and ecologically appropriate alternative. The present study aims to evaluate the resistance of Coffea canephora clones to Meloidogyne incognita. Evaluations were carried out in a greenhouse at Embrapa Rondônia (Porto Velho -RO) between September 2019 and November 2020. Genotypes were inoculated with M. incognita in four experiments with six replications with a completely randomized design. Root dry weight (RDW), the number of galls (NG) and the reproduction factor (RF) were evaluated. Eighty-six coffee clones were evaluated, with 50 clones showing resistance to Meloidogyne incognita and 36 clones showing susceptibility. Clones classified as resistant had an average reproduction factor of 0.33 with a range of 0.00 to 0.95, while clones classified as susceptible had an average reproduction factor of 3.48 with an amplitude ranging from 1.02 to 14.46. The number of galls was also higher in susceptible clones than in resistant clones. Considering the ten most cultivated clones, the genotypes GJ8, GJ25, P50, SK80, AS2, P42 and LB10 were classified as resistant, and the genotypes GJ3, GJ5 and SK41 were classified as susceptible. Taken together, the results identify resistant C. canephora clones as an important and sustainable tool for controlling M. incógnita.Item New model of clonal garden for the production of robusta coffee plantlets(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2022-09-12) Espindula, Marcelo Curitiba; Araújo, Larissa Fatarelli Bento de; Diocleciano, João Maria; Rocha, Rodrigo Barros; Dias, Jairo Rafael Machado; Verdin Filho, Abraão CarlosThe objective of this work was to evaluate the production of cuttings of Coffea canephora genotypes, in a new system for training mother plants called “vertical clonal garden”. The proposed new system consists of training coffee plants with only one shoot and without bending the main shoot, so that the secondary orthotropic shoots, from which the clonal cuttings will be taken, are formed across the length of the stem in the vertical direction. The capacity for the production of cuttings of ten hybrid genotypes of coffee plants was evaluated over ten production cycles. The 'BRS 2314', 'BRS 3213', and 'BRS 3210' genotypes showed cutting production per cut of 425,000 cuttings per hectare, considered above the obtained average. The 'BRS 3193', 'BRS 2336', 'BRS 3220', and 'BRS 3137' genotypes were the least productive. Coffee plants trained in the “vertical clonal garden” system can produce about 425,000 cuttings per hectare per harvest period or about 1.275 million cuttings per hectare per year, over three harvest periods, with a greater ease in crop management and treatments.Item Expression of self-incompatibility in Coffea canephora genotypes grown in the western Amazon(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2022-12-05) Depolo, Rodrigo Prado; Rocha, Rodrigo Barros; Souza, Carolina Augusto de; Santos, Maurício Reginaldo Alves dos; Espindula, Marcelo Curitiba; Teixeira, Alexsandro LaraThe objective of this work was to characterize the expression of gametophytic self-incompatibility in a Coffea canephora breeding population, to assist in the management and development of new cultivars. For that purpose, 550 in vitro pollinations were carried out among 62 parent plants, of which 27 were from the conilon botanical variety and 35 from the robusta. Thirty-two genotypes compatible with all previously known testers were identified, suggesting the existence of new compatibility groups. From these results, hybridizations were carried out in a complete diallel design with reciprocal crosses to characterize new test plants. Based on the compatibility response with the test plants, the genotypes were clustered into the six following groups: group I, 11 (17.74%) genotypes; group II, 13 (20.97%); group III, 6 (9.68%); group IV, 9 (14.52%); group V, 8 (12.90%); and group VI, 15 (24.19%). The genotypes of the botanical variety robusta show a higher frequency of plants in compatibility group VI and a greater genetic variability, whereas those of the conilon variety have a higher frequency of plants in compatibility group II. The identification of new compatibility groups assists in new management practices that seek to increase the efficiency of pollination by favoring, through natural means, fully compatible crosses.Item Factor analysis for plant and production variables in Coffea canephorain the Western Amazon(Universidade Federal de Lavras, 2022-06-09) Silva, Gabi Nunes; Barroso, Laís Mayara Azevedo; Cruz, Cosme Damião; Rocha, Rodrigo Barros; Ferreira, Fábio MedeirosThe evaluation of morphological characters related to the hulled coffee yield subsidizes the selection of Coffea canephora plants that combine a set of favorable traits. However, the greater the number of traits considered, the more difficult the selection process becomes. In this context, multivariate analyzes can be useful to overcome this problem. The aim of this study was to identify, in a set of agronomic traits of Coffea canephora, the determining factors of biological phenomena and use these factors to recognize patterns of diversity and similarity from biological complexes of interest to the breeder. To this, eleven morphological descriptors were evaluated of 130 clones of the botanical varieties Conilon and Robusta and intervarietal hybrids over two crop years in the experimental field of Embrapa, in the municipality of Ouro Preto do Oeste, state of Rondônia (RO). To group the traits, the multivariate technique of Factor Analysis was used. The effect of genotype x year interaction was significant for the eleven traits analyzed. Based on the scree plot, three factors were established. Factors were interpreted as architecture, vigor and grains with a satisfactory percentage of explained variability. The inter-pretation of the factors highlighted the importance of the Conilon variety to improve the architecture of the Robusta botanical variety. These results show that it is possible to use factor scores to identify varieties and traits that favor higher production of hulled coffee.Item Classification of Coffea canephora clones in botanical varieties by discriminant analysis of the k-nearest neighbors(Universidade Federal de Viçosa, 2021-11-08) Souza, Marciléia Santos; Ferreira, Fábio Medeiros; Rocha, Rodrigo Barros; Lopes, Maria Teresa Gomes; Oliveira, Leilane Nicolino LamarãoA strategy for genetic improvement of coffee Coffea canephora plants is to aggregate through artificial crossings the characteristics of the Conilon botanical variety, such as shorter height and drought resistance, with the higher average grain size and resistance to pests and diseases of the Robusta variety. Efficiently separating the clones into these two groups with the aid of appropriate analytical procedures makes field tasks easier for professionals and, thus, allows the systematic production of intervarietal hybrids. This study verifies if the non-parametric discriminant analyzes of the k-nearest neighbors (k-NN) and k-average neighbors (k-AN) would be able to correctly classify 130 coffee clones in their botanical varieties previously designated as Conilon, Robusta and Intervarietal Hybrids populations from ten quantitative agronomic characteristics, including the processed coffee beans yield, considering the existing population genetic divergence. These characteristics were found to be good discriminatory variables and the discriminant analyzes k-NN and k-AN, based on the principle of similarity by neighborhood, classified the clones with high hit rates. The k-AN discriminant analysis was able to better discriminate intervarietal hybrids from the group clones Conilon. The results correctly reflected the genetic diversity between the botanical varieties and intervarietal hybrids of Coffea canephora, allowing us to conclude that these classification methods can assist breeders in the main task of discriminating Conilon from Robusta clones.Item Yield of robusta coffee in different spatial arrangements(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2021-12-10) Espindula, Marcelo Curitiba; Tavella, Leonardo Barreto; Schmidt, Raquel; Rocha, Rodrigo Barros; Dias, Jairo Rafael Machado; Bravin, Maísa Pinto; Partelli, Fábio LuizThe objective of this work was to determine the contribution of the number of stems to the composition of individual plant yield, and to individual and overall robusta coffee (Coffea canephora) yield at different planting densities, using a fixed number of stems per plant. The experiment was carried out in two phases. The first phase was performed from 2011 to 2015, in the municipality of Ouro Preto do Oeste, in the state of Rondônia (RO), Brazil, to evaluate different numbers of stems per plant (1, 2, 3, 4, 5, and 6). The second phase was conducted from 2013 to 2018, in the municipality of Alta Floresta D’Oeste, RO, to evaluate plant densities (at 1,666, 1,904, 2,222, 2,666, and 3,333 plants ha-1), with an initial density of four stems per plant in all treatments. The increase of number of stems per plant promotes a quadratic response to the average and cumulated yield of coffee plants, and the maximum yield is attained with four stems per plant. The number of stems should not exceed four, to avoid their tipping during years of high production. Plant density of 3,333 plants per hectare, with 4 stems per plant and 1 m spacing, promotes the reduction of individual plant yield; however, it results in higher overall crop yield.