Use of morpho-agronomic traits and DNA profiling for classification of genetic diversity in papaya

Abstract

ABSTRACT. We examined the genetic diversity of papaya (Carica papaya) based on morpho-agronomic and molecular data. Twentyseven genotypes grown in Brazil were analyzed with 11 AFLP primer combinations, 23 ISSR markers, 22 qualitative, and 30 quantitative descriptors. For the joint analyses, we used the Gower algorithm (Joint Gower) and the average value of the individual dissimilarity matrix for each type of data (Average-Joint Gower); 359 AFLP and 52 ISSR polymorphic bands were found. Approximately 29.2 and 7.7% of the AFLP and ISSR bands, respectively, were genotype-specific and may therefore be used for papaya variety protection. Although there was a significant correlation between the qualitative and quantitative descriptor dissimilarity matrices (r = 0.43), the morpho-agronomic data were not highly correlated with the molecular data. Moreover, correlation between AFLP and ISSR dissimilarity matrices was nearly null (r = -0.01). Joint Gower analysis of all data showed high correlations, especially for AFLP markers, most likely due to the larger number of bands, generating ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 12 (4): 6646-6663 (2013) Germplasm characterization of papaya 6647 a strong bias in the diversity estimates. The Average-Joint Gower analysis allowed a better balance between the correlations for the continuous and the discrete variables. The results generated by clustering analysis distinguished 5 genetically distinct groups. While we found that papaya genotypes are significantly variable for many traits, we observed that Average-Joint Gower analysis allowed for genotype clustering based on the most widely used criterion for classifying papaya genotypes, which is fruit type ('Formosa' or 'Solo'). This information helps provide an accurate estimate of the genetic diversity and structure of papaya germplasm, which will be used for further breeding strategies.

Genetic variability and relationship studies in new Indian papaya (Carica papaya L.) germplasm using morphological and molecular markers

“…Several molecular markers, including random amplified polymorphic DNA (RAPD), intersimple sequence repeat (ISSR), and amplified fragment length polymorphism (AFLP), have been used for analysis of genetic diversity, relationships, and germplasm identification of papaya (de Jesus et al, 2013). Among the molecular markers, RAPD and ISSR markers have been extensively used to study genetic diversity and relationships in papaya germplasm (Rodríguez et al, 2010;Sudha et al, 2013).…”

Multivariate Analysis of Genetic Diversity among some Maize Genotypes under Maize-Albizia Cropping System in Indonesia

“…In maize sole cropping system, clustering resulted in nine main clusters with a point Euclidian coefficient of 4.8, level of dissimilarity between genotypes is high in the dendogram with a genetic distance of 0-0.8. In Maize-Albizia cropping system, five main clusters were formed with a point genotypes and this diversity could be utilized for cultivar breeding and germplasm conservation programs (Ali et al, 2011;De Jesus et al, 2013), particularly in breeding for Maize-Albizia cropping system.…”

Genetic Diversity Analysis among Papaya (Carica papaya L.) Varieties using RAPD Markers

“…Earlier morphological markers have been utilized for evaluation of genetic diversity among papaya germplasm [13,14]. With the development of advanced molecular markers, many researchers started to analyse the genetic diversity of papaya using various types of molecular markers viz, restriction fragment length polymorphism (RFLP) [15] random amplification of polymorphic DNA (RAPD) [16,17], amplified fragment length polymorphism (AFLP) [18][19][20][21], inter simple sequence repeat (ISSR) [16,21], simple sequence repeat (SSR) [12]. Therefore, the present study was aimed to evaluate genetic diversity among papaya cultivars and its related wild species using RAPD markers.…”