Diversity among genotypes of conilon coffee selected in Espírito Santo state / Diversidade entre genótipos de café conilon selecionados no estado do Espírito Santo

The use of multivariate techniques for factor analysis is an efficient alternative for coffee breeding programs. This study aimed to evaluate the genetic diversity of 60 genotypes of conilon coffee based on agronomic performance in the northern state of Espírito Santo and to estimate the relative contribution of different agronomic characteristics towards the diversity of the species. The data were collected in an experiment conducted on the Experimental Farm of Bananal do Norte (Instituto Capixaba de Pesquisa, Assistência Técnica e Extenção Rural ­ INCAPER) in the southern state of Espírito Santo, and 12 agronomic characteristics were evaluated over four sequential harvests (4 years). Significant differences between the genotypes were observed for all of the characteristics, indicating the possibility of exploiting the high genetic variability to classify the genotypes into different groups based on their similarities. Of the agronomic characteristics, the duration of the ripening cycle was the variable that contributed the most to the variability among the 60 genotypes, with a relative contribution of 70.02%.

A utilização de técnicas multivariadas de análise de fatores é uma alternativa eficiente utilizada no melhoramento genético do cafeeiro. O presente trabalho objetivou avaliar a divergência genética de 60 clones de café conilon, selecionados pelo seu desempenho no norte do Estado do Espírito Santo, e estimar a contribuição relativa de diferentes características agronômicas para a diversidade da espécie. Os dados foram coletados em experimento conduzido na Fazenda Experimental Bananal do Norte (INCAPER), considerando 12 características agronômicas, avaliadas através de médias de quatro safras. Diferenças significativas entre os genótipos foram observadas para todas as características avaliadas, indicando a possibilidade de exploração da alta variabilidade genética para a classificação dos genótipos em diferentes grupos homogêneos, baseado em suas similaridades. Dentre as características agronômicas, a duração do ciclo de maturação foi a variável que mais contribuiu para a variabilidade entre os 60 genótipos, com contribuição relativa de 70,02%.

Tolerance of arabica coffee cultivars for aluminum in nutritive solution

This work aimed to evaluate the Coffea arabica cultivars for aluminum toxicity tolerance, in modified Hoagland solution. A completely randomized design with five repetitions in a factorial 4 x 4 (cultivar x combinations of aluminum) was used. After 44 days of the sowing, were transferred ten seedlings each cultivar germinated in the absence of Al3+ to solution without Al3+, and ten for solution with Al3+; ten seedlings each cultivar germinated in presence of Al3+ to solution without Al3+, and ten for solution with Al3+. In the treatment with aluminum, the element was added to the nutritive solution in the concentration of 0.83 mmol L-1 as Al2(SO4)3.16H2O. The cultivars Catuaí Amarelo IAC 62 and Iapar 59 were tolerant to the aluminum; cultivar Oeiras presented intermediate tolerance, while cultivar Obatã IAC 1669-20 was sensitive. The tolerance of the coffee cultivars to the aluminum during the initial development of the seedlings did not depend on the presence of aluminum in the germination phase.