Coffea canephora breeding: estimated and achieved gains from selection in the Western Amazon, Brazil

Abstract

Gain from selection is an important criterion in quantifying the efficiency of breeding programs. This study quantified the selection gain estimated under experimental conditions and realized gain achieved in the field, seeking to interpret the efficiency of the Coffea canephora selection. For that purpose, we considered experiments that began in 2004 with directed hybridizations to obtain new hybrid progenies. From a breeding population composed of 288 hybrid individuals, 12 genotypes were selected in experimental conditions from 2005 to 2012, with amplitude in the estimated gains from 127.70 to−19.19%. Those genotypes were evaluated from 2012 to 2018 in clonal tests in four environments of the Western Amazon. The environment that exhibited the greatest correlation between the predicted genetic values and the realized genetic gain observed in the field was the environment of Ouro Preto do Oeste, RO (0.67), the location in which the plants were selected, followed by the environments of Alta FlorestaD´Oeste, RO (0.44), Rio Branco, AC (0.43), and Porto Velho, RO (0.37).Experimental conditions showed that the effect due to dominance deviations was approximately three times greater than the additive effect. Nine clones exhibited higher genetic gains in the experimental conditions and at field, and two clones exhibited lower estimated gains and lower field performance.The clone G17-P7 exhibited high genetic gain under experimental conditions and low field performance. The selection in experimental conditions was positively correlated with plant performance in the field (r=0.55), which allows reduction of the original breeding population to a set of more promising clones to be grown in multiple environments, optimizing time and resources.

Factor analysis for plant and production variables in Coffea canephora in the Western Amazon

“…The separation of Conilon and Robusta varieties in relation to scores associated with the architecture (Figures 2a and 2b) is related with the characteristics of these botanical varieties, since Robusta genotypes are taller and more vigorous plants, with larger leaves and fruits than Conilon genotypes (Rocha et al, 2021), which justifies the distribution of Robusta in quadrants I and IV (Figure 2a) and in quadrant II (Figure 2b).…”

“…The two botanical varieties of Coffea canephora are Conilon, which is more drought tolerant but has greater susceptibility to diseases, and Robusta, which are taller and more vigorous plants, with larger leaves and fruits, and has greater resistance to pests and diseases, but is less drought tolerant (Rocha et al, 2021). In Rondônia, in the Western Amazon, both botanical varieties are cultivated.…”

Resistance of Coffea canephora as a sustainable tool for Meloidogyne incognita control

“…The botanical variety Robusta is characterized by erect growth, larger leaf size, a higher average sieve, late maturation, less tolerance of water deficits, and greater resistance to diseases and pests. The botanical variety Conilon is characterized by shrub growth, early maturation, elongated leaves, greater tolerance to drought, and greater susceptibility to pests and diseases (Rocha et al, 2021).…”

“…Given the occurrence of M. incognita in coffee plantations in the state of Rondônia, the identification of genotypes that are resistant and adapted to infested areas is of great importance for associated crop management (Santos et al, 2017). The genetic improvement provides science that contributes to the adaptation and increased production of crops (Ferrão et al, 2021, Rocha et al, 2021, Grenier et al, 2015. In infested areas, the use of resistant cultivars is an economically viable and environmentally appropriate tactic for nematode control.…”

Genetic gains for obtaining improved progenies of oil palm in Colombia

“…The success of breeding programs depends on genetic variability; in practice, the utility of genetic gain through selection allows for better breeding criteria for selecting genetically superior individuals (Gomes Junior et al 2021). In evaluating, selecting, and developing individuals who show genetic superiority in agronomic traits, estimating genetic gains becomes essential for the industry's success for different crops (Pavlotzky and Murillo 2014;Rocha et al 2021).…”