Heritability Estimates of Guava (Psidium guajava']java L.) Agricultural Important Characters Evaluated in Three Populations

Most economically significant fruit traits show quantitative variation which is controlled by a combination of genetic and environmental factors. In order to improve quantitative traits successfully in any plant breeding program, genetic and environmental effects need to be evaluated. Guava (Psidium guajava L.) is the most valuable cultivated fruit species of the Myrtaceae family. The inheritance studies of quantitative characters in this species are insufficient worldwide and in Cuba they have not been approached up to date. Three populations of guava were planted according to a Complete Random Design at the Tropical Fruit Tree Research Institute, Havana Province, Cuba. Fourteen quantitative fruits traits were evaluated during a period of four years. Factorial Analyses of Variance (Model II) were done with data sets with the aim of estimating the variance components and the heritability in broad sense. The heritability in narrow sense was estimated by a progeny-progenitor regression analysis. These analyses were made using the statistical program SPSS. In the three populations, most of the characters presented low and medium values of heritability in broad sense, with the exception of calix diameter-fruit ratio that showed a high heritability estimate in one of the populations. The length of fruit showed high values of heritability in narrow sense, while the other traits presented low and medium values. Most of the variables showed a genotype x environment interaction variance that was statistically significant, which facilitates the application of a better refined model for the genotype x environment interaction analysis.