Initial development and sample dimensioning of rubber tree clones

Abstract

The current success of rubber cultivation is related to the use of clones adapted to different edaphoclimatic regions. Hence, it is important to evaluate variables that are correlated with yield. However, a common problem is choosing the plot dimensions where these variables will be measured. In view of the above, the objective of this work was to evaluate the initial development of two rubber tree clones and to determine the ideal sample unit size to characterize trunk circumference, tree height and bark thickness. The variables circumference at breast height (CBH), total height (Ht) and bark thickness (BT) were measured in seven plots of 680.4 m², in addition to determining the plot size to satisfactorily sample each of the variables measured in each clone, 52 months after planting. At 52 months, clone RRIM 937 showed better development than RRIM600 in relation to the analyzed variables. The ideal sample unit size is different for the variables in the following order: trunk circumference> total height> bark thickness. The measurement of plots with 15 trees is adequate to represent the variability of the analyzed variables, considering the acceptable error of 10%.