Entity

Time filter

Source Type


Febles G.,Institute Ciencia Animal | Torres V.,Institute Ciencia Animal | Banos R.,Institute Pastos y Forrajes | Ruiz T.E.,Institute Pastos y Forrajes | And 2 more authors.
Cuban Journal of Agricultural Science | Year: 2011

An experiment was designed to know the impact index. The application of this technique admits combinations of species within each edaphoclimatic region. The impact index depends on the indicators of higher preponderance that appear in the analysis of the principal components and corresponding with them. The result generates values that, according to their number hierarchy, express the highest or the lowest effect of each indicator per region. The data came from farms for seed production, located in specific regions of the Cienfuegos, Villa Clara, Sancti Spíritus, Camagüey, Granma and Guantánamo provinces. The species were: Panicum maximum, Andropogon gayanus, Brachiaria decumbens, Brachiaria brizantha, Chloris gayana and Cenchrus ciliaris. The results showed the preponderance of the factors: total rainfall and rainfall in the rainy season; maximum, medium, and minimum temperatures; effective depth; amount of rocks; and light hours. The indicators of the first component had the highest impact index in Guantánamo, followed by Granma and Camagüey. They showed lower value in Cienfuegos, with more negative figures. In the first impact index, 45.4 % of the indicators of higher preponderance were found in the analysis of the principal components. Andropogon gayanus reached the highest values in Guantánamo, Granma and Camagüey, being followed by Panicum maximum, Cenchrus ciliaris and Brachiaria brizantha, respectively. This result showed a closer relationship between the species in the regions under study. It is concluded that the mathematical methods used were potentiated by the determination of the impact index. The importance of the methodology is discussed, as well as the study of the localities and the possible effect of the impact index on the interaction genotype-environment. Source


Febles G.,Institute Ciencia Animal | Torres V.,Institute Ciencia Animal | Banos R.,Institute Pastos y Forrajes | Ruiz T.E.,Institute Pastos y Forrajes | And 2 more authors.
Cuban Journal of Agricultural Science | Year: 2011

The trial was conducted to develop a strategy for determining the production of tropical prairie seeds with greater accuracy, through the combination of edaphoclimatic indicators and multivariate analysis of principal components and conglomerates. The data were collected from farms with seeds sown in specific regions of Cienfuegos, Villa Clara, Sancti Spiritus, Camagüey, Granma and Guantanamo. The species were Panicum maximum, Andropogon gayanus, Brachiaria decumbens, Brachiaria brizantha, Chloris gayana, and Cenchrus ciliaris. The results showed the preponderance of the variables: total rainfall and rainfall in the rainy season; maximum, minimum and mean temperature; soil depth, rocks, phosphorus, and drainage. The method of conglomerates produced four groups: Cienfuegos; Guantánamo, Villa Clara and Camagüey; S. Spiritus; and Granma. These variables accounted for 88.8 % of the variability in the analysis of conglomerates. The mathematical analysis showed that there was no relevance for the yield, which varied between 147.8 and 240 kg/ha. This may indicate that the species performance does not vary, in a relevant form, between regions. It was concluded that the combined method was useful to study the influence of the composite of edaphoclimatic factors, species, and regions of the country. Source

Discover hidden collaborations