Collection of hevea materials from Rondonia territory in Brazil a preliminary study

Abstract

Seven characteristics were studied in 27 selected wild mother trees at Ouro Preto, Rondônia Territory: yield, circumference, bark thickness, total number of latex vessels, density of latex vessels per 5 mm per ring, and average distance between consecutive latex vessel rings. All the trees were also evaluated for the degree of incidence of South American Leaf Blight (SALB). Great variability was observed among the individual selected rubber trees growing under similar environmental conditions. Linear correlations among the quantitative characteristics were estimated. Positive correlations were found between yield and circumference, bark thickness, total number of latex vessel rings and density of latex vessels per 5 mm per ring. Low relationship was found between yield and diameter of the latex vessels and between yield and average distance between consecutive latex vessel rings. Regression analysis of yield and the values of the quantitative characters showed the regression coefficient to be highly significant to circumference, bark thickness, total number of latex vessel rings and density of latex vessels per 5 mm per ring.