Morphological and agronomical characterization of cassava Clones cultivated on the Roraima State, Brazil

Abstract

The objective of this study was to evaluate the production components and to morphologically characterize the cassava clones cultivated on the Roraima State, Brazil. The research was carried out during the period of 1999 to June 2000, in the experimental area of the CCA-UFRR, in Boa Vista. The experiment was set up in a randomized block design, with three repetitions, in split plot, in which the clones were in the blocks and the harvest periods in the split plot. The spacing 1.0 x 0.5 m was used. The blocks were composed by three lines of 10 m, with 1.0 m border on each end leaving one line on each side of the blocks as side border. The evaluations were made at seven and thirteen months after planting. For the evaluation, the useful block was divided into four equal parts of 2.0 m in lenght and two parts taken at random for the evaluations at each data collection period. All the clones were different from each other. The clone MX-09 was the only one to present leaves with five lobes. The root diameter was a better parameter to distinguish the clones than
the root length. The greatest productivities were obtained with clones MX-01, MX-04, and MX-10, corresponding to 3.5 times the average productivity of the State of Roraima.