Eficiência da seleção de progênies de café F4 pela metodologia de modelos mistos (REML/BLUP)

Abstract

ResumoObjetivou-se verificar a eficiência da seleção de cafeeiros em geração F 4 para características agronômicas e resistência a doenças mediante o emprego da metodologia de modelos mistos de Henderson. O experimento foi instalado na Fazenda Experimental da EPAMIG, em Machado, MG, sendo utilizadas progênies F 4 derivadas do cruzamento entre cultivares do grupo Icatu com Catuaí Amarelo IAC 62 e IAC 17 e com as progênies IAC 5002 e IAC 5010. O delineamento experimental utilizado foi o látice com quatro repetições e as avaliações foram realizadas ao longo de dois anos (2010 e 2011). Foram avaliadas as seguintes características: produção (litros planta -1 ), reação à ferrugem, vigor vegetativo e reação à cercosporiose. Foram utilizados o procedimento REML/BLUP para estimar os parâmetros genéticos, o índice de seleção de Mulamba e Mock a fim de verificar os ganhos para múltiplos caracteres, a acurácia e eficiência, calculadas a partir do diferente número de medições e, ainda, o agrupamento multivariado de progênies pelo método de Tocher. Verificou-se, a partir da análise dos parâmetros genéticos, um maior sucesso na seleção entre famílias para todas as características avaliadas. A adoção de quatro colheitas poderá elevar a acurácia a 80% na seleção de indivíduos para as características produção, reação à ferrugem e vigor vegetativo. A seleção das 12 melhores progênies para caracteres múltiplos pelo índice de Mulamba e Mock proporcionaria um ganho médio de 70,4%.Palavras-chave: Coffea arabica, seleção precoce, Icatu, melhoramento genético. Selection efficiency of F 4 coffee progenies by mixed model methodology (REML/BLUP) AbstractThe aim of this paper was to evaluate the selection efficiency in the F 4 generation of coffee for agronomic traits and disease resistance through the use of mixed model methodology of Henderson. The experiment was carried out in Machado (MG) Brazil, using F 4 progenies from a cross between cultivars of Icatu group with Catuaí Amarelo IAC 62 and IAC 17 and with the progenies IAC 5002 and IAC 5010. The experimental design was a square lattice with four replications and the evaluations were taken during two years (2010 and 2011). The traits evaluated were: production (L plant -1 ), reaction to rust, vegetative vigor and reaction to Cercospora. We used the REML/BLUP procedure to estimate genetic parameters, the Mulamba & Mock selection index to verify the gains for multiple characters, the accurary and efficiency and also the multivariate clustering progenies through the Tocher method. The analysis of genetic parameters using mixed models was successful for selecting families for all characteristics under consideration. The adoption of four crop harvests may increase to 80% the accuracy in selecting individuals for production characteristics, reaction to rust and vegetative vigor. The selection of the 12 best progenies for multiple characters by Mulamba and Mock index provided an average gain of 70.4%.

Selection of Coffee Progenies With Large Beans Resistant to Rust and Cercospora Leaf Spot

“…Bernardo (2010) noted that information on statistical variability is fundamental to understanding population genetics. A recent prediction methodology to characterize populations of perennial species is the restricted maximum likelihood/best linear unbiased prediction (REML/BLUP) (BALZARINI, 2001;PEREIRA et al, 2013). Data analysis in coffee experiments has benefited from using REML/ BLUP because coffee is a perennial crop with For cercospora leaf spot, severity was calculated according to the formula:…”

Simultaneous selection for cowpea (Vigna unguiculata L.) genotypes with adaptability and yield stability using mixed models

“…Lastly, it generates results within the range of the trait measured, which can be directly interpreted as breeding values (Verardi et al, 2009;Freitas et al, 2013). The HMRPGV method has been used in perennial and semi-perennial crops, such as coffee (Pereira et al, 2013;Rodrigues et al, 2013;Carias et al, 2014), eucalyptus (Rosado et al, 2012), cashew (Maia et al, 2009), and passion fruit (Santos et al, 2015a). Its use in annual crops is still in its early stages, although an increasing number of studies have proved its effectiveness in crops such as cowpea (Torres et al, 2015) and rice (Regitano Neto et al, 2013).…”

Yield, maturation cycle, and estimates of genetic parameters of Robusta coffee genotypes under irrigation in the Cerrado

“…Fonseca et al (2004) cited that four successive harvests would be sufficient for selection of robusta coffee genotypes for yield with an accuracy of 80%, a value also considered quite satisfactory by Resende (2009), for whom selective accuracy between 0.7 and 0.9 is considered high. Pereira et al (2013) obtained estimated accuracy of 0.84 in three harvests in an experiment with four repetitions in two years. In the experiment described here, the accuracy obtained in three harvests was approximately 75%, and estimated at 79% with four harvests, very close to the values obtained by the authors cited.…”

“…Thus, the standard analytical procedure that has been recommended for studies in quantitative genetics and also for selection in perennial plants is the mixed model methodology. This approach allows accurate and unbiased prediction of the genetic values even under imbalance, and it also facilitates simultaneous use of information on the individual and the family and of measures repeated over time, providing more accurate estimates of the components of genetic variation and of individual genetic values (Pereira et al 2013).…”