Morphological phenotypic dispersion of garlic cultivars by cluster analysis and multidimensional scaling

• Published in: Scientia agricola Vol. 71; no. 1; pp. 38 - 43
• Main Authors: Silva, Anderson Rodrigo da, Cecon, Paulo Roberto, Dias, Carlos Tadeu dos Santos, Puiatti, Mário, Finger, Fernando Luiz, Carneiro, Antônio Policarpo Souza
• Format: Journal Article
• Language: English; Portuguese
• Published: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" 01.02.2014; Universidade de São Paulo
• Subjects: AGRICULTURE, MULTIDISCIPLINARY; Allium sativum L; genetic divergence; nMDS; UPGMA; UPGMA; Allium sativum L; genetic divergence; nMDS
• ISSN: 0103-9016; 1678-992X; 0103-9016; 1678-992X
• DOI: 10.1590/S0103-90162014000100005

Multivariate techniques have become a useful tool for studying the phenotypic diversity of Germplasm Bank accessions, since they make it possible to combine a variety of different information from these accessions. This study aimed to characterize the phenotypic dispersion of garlic (Allium sativum L.) using two multivariate techniques with different objective functions. Twenty accessions were morphologically characterized for bulb diameter, length, and weight; number of cloves per bulb; number of leaves per plant; and leaf area. Techniques based on generalized quadratic distance of Mahalanobis, UPGMA (Unweighted Pair Group Method with Arithmetic Mean) clustering, and nMDS (nonmetrric MultiDimensional Scaling) were applied and the relative importance of variables quantified. The two multivariate techniques were capable of identifying cultivars with different characteristics, mainly regarding their classification in subgroups of common garlic or noble garlic, according to the number of cloves per bulb. The representation of the phenotypic distance of cultivars by multidimensional scaling was slightly more effective than that with UPGMA clustering.