Correlation and heritability analysis in breeding of camu-camu [Myrciaria dubia (Kunth) McVaugh]

Abstract

Between 2002 and 2011 in Peru and Brazil, there have been made studies of correlation and heritability in search of tools for genetic improvement of camu-camu. This work is intended to systematize successful information aiming at the consolidation of criteria for the selection of higher plants. The author evaluated basic collections, progenies and clones existing in experimental centers belonging to INIA (Instituto Nacional de Innovación Agraria), IIAP (Instituto de Investigaciones de la Amazonia Peruana) and INPA (Instituto Nacional de Pesquisas da Amazonia). The length of petiole (LP) has an intermediate heritability (in the broad sense) of h2g = 0.42 and correlation coefficients of r2 = 0.37 for fruit yield and r2 = 0.54 for fruit weight. Basal branch number (NRB) also shows levels of heritability average (in the strict sense): h2a = 0.45 and h2g = 0.33 in the broad sense. NRB in turn significantly correlated with fruit yield (FY): r2 = 0.43; fruit weight (FW): r2 = 0.38 and ascorbic acid (AA): r2 = -0.30. The values of pH and soluble solids (degrees Brix) of the pulp showed a high correlation with AA (r2 = 0.85 and r2 = 0.94, respectively). It is emphasized that the parameters, number of basal branches, petiole length and fruit weight that present a relatively high correlation with fruit yield also have an intermediate level of heritability, which qualifies them as important tools for the selection of superior plants of camu-camu.