Genetic relatedness of Portuguese almond cultivars assessed by RAPD and ISSR markers

Abstract

Randomly amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers were used to analyse the genetic diversity of Portuguese Prunus dulcis cultivars and their relationship to important foreign cultivars. Of the primers tested, 6 (out of 60) RAPD and 5 (out of 18) ISSR primers were selected for their reproducibility and high polymorphism. Out of 124 polymerase chain reaction fragments that were scored, 120 (96.8%) were polymorphic. All the plants could be discriminated and constitute a very heterogeneous group. Five unidentified almond plants found in the region of Foz Côa (north Portugal) and wild almond (P. webbii) from Italy and Spain were also included. Four main groups of plants could be distinguished: P. dulcis cultivars; one Foz Côa plant; P. webbii; and P. persica (outgroup). The segregating Foz Côa plant may represent a feral individual or a hybrid between P. dulcis and P. webbii.

Assessment of Genetic Diversity of Moroccan Cultivated Almond (<i>Prunus dulcis</i> Mill. DA Webb) in Its Area of Extreme Diffusion, Using Nuclear Microsatellites

“…Using the RAPD method, Mir Ali and Nabulsi [63], found that genetic diversity of Syrian almonds exceeds that found by Bartolozzi et al [31] who reported a low variability in RAPD markers among California almond cultivars. In the same direction, Martins et al [32,33] found considerable polymorphism in the Portuguese almond collection. Therefore, the genetic diversity of the almond trees tends to be more restricted toward the Western Mediterranean as compared to the East, as reported by Delplancke et al [5].…”

“…Currently, DNA markers are widely used in studies of genetic diversity and the clarification of certain research questions, among others, those concerning their genetic origin [9]. These tools have evolved over time and the initial studies were based on isozymes [23][24][25][26][27][28], RFLP [28], RAPD [29][30][31][32][33][34], ISSR and AFLP [32,33]. The relatively recent use of microsatellites (simple sequence repeat: SSR) in the characterization of Prunus species and other perennial fruit species showed their power of discrimination [9,[35][36][37][38][39][40].…”

In VitroMicrografting of the Almond Cultivars “Texas”, “Ferrastar” and “Nonpareil”

“…however, genetic analysis of almond plantlets propagated with axillary branching (21) and adventitious regeneration and meristem culture (22) showed genetic integrity of the plantlets. But it is well-known that tissue culture conditions result in physiological stress that can lead to impairment of normal developmental controls and trigger the mechanism of somaclonal variation (14).…”

Genetic relationships and origin of commercial clones of Nangouhi, a vegetatively propagated cultivar of hinoki cypress (Chamaecyparis obtusa)

“…In horticulture, mutant sprouts of specific cultivars are often used to produce new cultivars (Testolin et al 2000, Martins et al 2003, Yamamoto et al 2003, Hu et al 2005, Soriano et al 2005. Microsatellite genotypes of mutant sprouts are identical or very similar to each other.…”