Genetic diversity of table grape based on morphoagronomic traits

Patrícia Coelho De Souza Leão,Cosme Damião Cruz,Sérgio Yoshimitsu Motoike

doi:10.1590/s0103-90162011000100007

Abstract

The conservation and characterization of grape (Vitis spp) genetic resources in germplasm banks have been the basis of its use in breeding programs that result in development of new cultivars. There are at least 10,000 grape cultivars kept in germplasm collection. The genetic diversity in 136 table grape accessions from the state of Bahia, Brazil, was evaluated. Continuous and discrete morphoagronomic traits were assessed. The clustering analysis by the Tocher otimization method resulted in 30 clusters (considering continuous morphoagronomic traits), and 9 clusters (taking into consideration multicategorical traits). There was no agreement between clusters obtained by both, continuous or discrete phenotypic descriptors, independent of the cluster method analysis used. A satisfactory genetic variability among the table grape accessions was observed.

Highlights

Methods based on morphoagronomic traits, used to study genetic diversity, have been used since Mendel’s time
The ampelography is the field of botany concerned with identification and classification of grape anchored in morphological traits of leaves, apical shoot tips, bunches, and berries (IPGRI, UPOV, OIV 1997; Galet 1998)
Clusters 1 and 2 grouped cultivars of different geographical origins, different species such as Vitis vinifera, Vitis labrusca, Vitis interspecific hybrids, and seeded and seedless grape cultivars. These results agree with those obtained in guarana (Paullinia cupana Kunth.) (Nascimento Filho et al, 2001) and cowpea (Vigna unguiculata L.) (Oliveira et al, 2003), where there was no occurrence of correlation between geographical and genetical diversity

Summary

Introduction

Methods based on morphoagronomic traits, used to study genetic diversity, have been used since Mendel’s time. The ampelography is the field of botany concerned with identification and classification of grape anchored in morphological traits of leaves, apical shoot tips, bunches, and berries (IPGRI, UPOV, OIV 1997; Galet 1998). The ampelography was the predominant method for grape germplasm characterization, since XIX century, until the advent of molecular markers. The predictive methods based on morphological, agronomical, physiological or genetical traits of genitors, determined prior to the crosses, may help breeders to focus in promising combinations (Cruz et al, 2004). The multivariate techniques in the analysis of quantitative and qualitative characteristics have been applied in viticulture with several objectives: to assess the diversity of genotypes for disease resistance (Nascimento et al, 2006), management (Intrieri et al, 2001), and morphological and agronomic descriptors (Borges et al, 2008; Micheli et al, 1993; Cravero et al, 1994; Matheou et al, 1995a; Matheou et al, 1995b; Boselli et al, 2000; Coelho et al, 2004)

Methods

Results

Conclusion