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Item Sample size estimation of fruit maturation for Arabica’s coffee(Instituto Agronômico (IAC), 2025-01-31) Botega, Gustavo Pucci; Abrahão, Juliana Costa de Rezende; Botelho, Thiago Tavares; Botelho, Cesar Elias; Salvador, Guilherme Soares; Gonçalves, Flávia Maria AvelarThis study aimed at establishing the ideal sample size for evaluating the maturation cycle in Coffea arabica, and investigating the errors associated with different sample sizes, in addition to verifying the possibility of using the clustering method to separate genotypes according to the maturation stage. Two experiments were analyzed: one with F2:3 progenies using visual maturation assessment through fruit counting, and another with cultivars using image processing for maturation assessment. To determine the ideal sample size for this trait, we used the estimation of the errors associated with maturation, using the bootstrap technique. Subsequently, the K-means algorithm was tested as an alternative for clustering genotypes into maturation classes. The application of the bootstrap technique in order to estimate the error associated with maturation revealed that the adoption of a 450-mL sample size resulted in an associated error of approximately 5%, indicating that it is an adequate size for character assessment. The implementation of K-means as a clustering tool offers a promising perspective for Arabica coffee plant breeding programs. A more comprehensive analysis, which not only assesses the proportion of ripe fruits, but also considers the distribution of different maturation stages, provides a more accurate understanding of the maturation process. This allows a more precise identification of genotypes with the most suitable performance for different growing conditions, as well as enabling adjustments in harvest management and post-harvest processing, optimizing coffee quality.Item Potential of new Coffea arabica cultivars for renewal of Meloidogyne paranaensis infested crop(Instituto Agronômico (IAC), 2025-06-09) Luz, Silvana Ramlow Otto Teixeira da; Teixeira, Lívia Pimenta; Salgado, Sonia Maria de Lima; Andrade, Vinícius Teixeira; Marques, Elizabeth Rosemeire; Botelho, Cesar Elias; Fatobene, Bárbhara Joana dos Reis; Carvalho, Gladyston RodriguesMeloidogyne paranaensis is one of the most damaging species of root-knot nematode to coffee trees. The development of resistant cultivars is crucial to the continuity of cultivation in infested areas. Thus, the aims of this study were to assess the performance of F6:7 progenies derived from the Amphillo germplasm in an infested area and to validate the new Coffea arabica MGS Vereda and MGS Guaiçara cultivars. The Catuaí Amarelo IAC 62 cultivar was used as the susceptible standard, and IPR 100 as the resistance standard. The experiment was conducted in 2018 using a randomized complete block design with four replications and 15 plants per plot. Resistance related and agronomic traits were assessed over four years. The lowest population of M. paranaensis was observed in progenies 88, 44B, and 105 from MGS Guaiçara, MGS Vereda, and IPR 100 cultivars, respectively. The progenies with the lowest population of M. paranaensis, although resistant, were not productive. The new MGS Vereda cultivar stood out in terms of yield and early fruit ripening, with the highest proportion of cherry fruit at harvest and a low incidence of peaberry grain. The results suggest MGS Vereda cultivar’s potential for the renewal of coffee cultivations occurs in a rainfed system according to the environmental conditions of the experiment.