A. R. Ramalho

Componentes primários e secundários do rendimento de óleo de pinhão-manso

The definition of the most suitable plant selection criteria is especially important for Jatropha curcas L. as subsidies the genetic progress estimates and the ideotype characterization, described in terms of the traits that are thought to enhance genetic yield potential. The objective of this study was to estimate the direct and indirect effects of seven vegetative traits and four seed quality traits on J. curcas oil yield. The traits grain yield and the weight of the nuts showed direct and positive effect on the oil yield. The tree volume showed the major indirect and positive effect on the main variable through grain yield. The development of J. curcas with higher oil yield in the evaluated population has to consider the selection of plants with higher yield and tree volume, maintaining the variability of the grain quality traits.

Eficiência da seleção para incremento do teor de óleo do pinhão-manso

The objective of this work was to estimate the genetic parameters of physic nut (Jatropha curcas) grain quality traits and to quantify the genetic progress with selection. Seed oil content, and seed, kernel, and shell weights of 120 plants, randomly selected in a commercial planting, were evaluated at 36 and 48 months. Genetic progress was quantified by the evaluation of direct gains and by the use of selection indexes. The genotype x measurement interaction was significant for all evaluated traits; therefore, there are genotypes with different behavior in the two cropping seasons. The genetic parameters indicated a higher proportion of genotypic variation in the expression of the evaluated traits, and a trend of the genotypes to maintain their genetic superiority over time was observed. The genotype-ideotype selection index resulted in higher genetic gains and promoted a more balanced alteration in the trait means. The direct selection for kernel weight results in genetic gains similar to those obtained with the use of the selection indexes.

Aumento da produção de grãos de pinhão-manso pela aplicação de benziladenina

The objective of this work was to quantify the flowering and grain production of physic nut (Jatropha curcas) in response to application of benzyladenine directly on closed inflorescences. The experiment was carried out in field, with plants at productive age and high-crop density. The following variables were considered: number of female and male flowers per inflorescence, number of inflorescences and bunches per plant, number of fruit per bunch, percentage of fruit abortion, and grain yield per plant. The application of the plant regulator enhanced the number of female flowers per plant, increasing the number of fruit per bunch in 170%. Despite the lower fruit setting of treated plants, the application of benzyladenine increased grain yield in 92%.

Progresso genético da produtividade de café beneficiado com a seleção de clones de cafeeiro 'Conilon'

A especie Coffea canephora Pierre ex Froehner possui ampla distribuicao geografica, com ocorrencia em regioes tropicais de diversos continentes. Aproximadamente 30% da producao brasileira de cafe e proveniente do cultivo dessa especie, sendo que o Estado de Rondonia se destaca como seu segundo maior produtor. Este trabalho teve como objetivo estimar os parâmetros geneticos com a selecao de clones de C. canephora, da variedade botânica ´Conilon’, visando caracterizar a variabilidade genetica e estimar o progresso genetico da produtividade de cafe beneficiado. A analise de variância da producao de cafe beneficiado evidenciou que a fonte de variacao “clones” foi significativa nas safras avaliadas, de acordo com o teste F a 1% de significância. A predominância do componente genetico na expressao dessa caracteristica, associado a uma boa precisao experimental, indica a possibilidade de obtencao de ganhos com a selecao de plantas. O progresso genetico da producao de cafe beneficiado com o plantio dos clones selecionados foi de 57,85%, que equivale a um aumento na media em quatro anos de 44,75 sacas ha-1, para 70,64 sacas ha-1. Alem do incremento na produtividade de graos, os clones de ciclo intermediario selecionados favorecem a concentracao da colheita e a reducao dos custos operacionais.

Yield, maturation, and beverage quality of arabica coffee progenies under selection in Rondonia state, Brazil

In this paper, we studied coffee bean yield, maturation, and other characteristics of special progenies of Arabica coffee (Coffea arabica L.) grown under high temperatures in a low altitude region in the state of Rondonia, Brazil. We evaluated 29 progenies developed by the Instituto Agronomico de Campinas ? IAC, namely, 24 F2BC2 progenies of Obata (C. arabica with introgressions of C. canephora) x (C. eugenioides 4n x C. arabica), three F3 progenies of Catuai x Glaucia, and two H419 lines. Seven cultivars were used as controls. A randomized block design was used with three replications, spacing of 3.0 × 1.0 m, and ten plants per plot. All the crop seasons showed a significant difference for the hulled coffee yield trait. In combined analysis, significant difference was detected among progenies, among controls, and in the progeny vs control contrast. In the average of the four harvests, hulled coffee yield was 29.30 bags ha-1. The F2 progeny Obata x (Catuai x EUG DP x MN) C.1594 stood out from the others with a mean yield of 47.37 bags ha-1. The cultivars received beverage scores from 40 to 62, ?rioysh? to ?hard? beverage classification, while the progenies had scores from 40 to 80, ?rio? to ?barely soft? beverage classification. In regard to the maturation cycle, eleven progenies were late (April), eleven intermediate (March), and seven early (February). For continuity of advancement of generations, 104 plants were selected, derived from 22 progenies with the best productive performance, late maturation cycle, and good beverage quality.