The genetic diversity of 74 chili pepper accessions (Capsicum spp.) was evaluated with amplified fragment length polymorphisms (AFLPs). Thirty‐four accessions were collected from home gardens throughout the Department of Alta Verapaz, Guatemala. The remaining accessions were selected from the national ex situ germplasm collection representing the diversity of 12 other departments of Guatemala. Most of the accessions belong to Capsicum annuum L., both cultivated and semicultivated types. A few accessions of C. chinense Jacq., C. frutescens L., and C. pubescens Ruiz & Pavon were also included. The analysis of banding patterns (68 polymorphic bands) were obtained with three AFLP primer combinations (+3/+4 and +4/+3 selective bases) and allowed the discrimination of all but two of the accessions examined. It also made it possible to conclude that the genetic diversity found in the home gardens of Alta Verapaz is representative of the total genetic diversity of Capsicum in Guatemala. This is the first time that molecular markers have been used to assess crop genetic diversity maintained in home gardens and to evaluate their importance for in situ conservation of genetic resources.

Capsicum species are of great economic, medicinal, culinary and cultural value worldwide, however their genetic potential is still underutilized. In this study, a set of 21 microsatellite markers showed utility for distinguishing a diverse group of 42 Capsicum genotypes representing 11 species. The level of polymorphism among these genotypes was evaluated by calculating the polymorphic information content (PIC) and discriminating power (D) for each locus. A total of 208 alleles were detected at the 21 loci evaluated. Markers detecting the highest number of alleles also exhibited the highest number of rare alleles. PIC values and D estimations showed a significant positive correlation (r = 0.98; P \ 0.0000). PIC values ranged between 0.500 (marker NG20) and 0.899 (marker NG17), giving an average of 0.775. Genetic relationships among genotypes were evaluated using UPGMA clustering, Principal Coordinate Analysis (PCoA) and Bayesian model-based clustering, allowing genotypes to be discriminated into groups according to their degree of genetic similarity corresponding to distinct taxa. Based on these analyses, the 21 microsatellite included in this study now define a standard tool for efficient assessment of molecular variability of Capsicum germplasm collections conserved worldwide.

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The genetic diversity of 76 accessions of lima bean (Phaseolus lunatus L.), collected mostly from home gardens, was assessed with AFLPs and seed descriptors to evaluate the potential for recovering a lost ex situ collection in Cuba. The sample contained 60 accessions collected from 25 home gardens in the three main geographical regions of Cuba and represented the three cultivated types found on the island. Four more accessions were part of the former ex situ collection and the remaining 12 accessions were selected from the world bean collection held at the International Center for Tropical Agriculture. Some morphological measurements discriminated among cultivated types. The analysis of 62 polymorphic bands obtained with two AFLP primer combinations indicated that the three cultivated bean types were comparable in terms of molecular diversity and that no pattern of variation was associated with geographical distribution. However, a multiple correspondence analysis with the same molecular data detected different genetic groups. Three of these groups included all the cultivated accessions collected from home gardens, but could not be explained by the seed descriptors. The results therefore suggest that a scientifically sound collecting strategy to recover the former Cuban ex situ gene bank should consider combining geographical, morphological, and molecular data. The findings also suggest that any proposed methodologies should be considered before developing a conservation strategy based on an ex situ or combined ex situ and in situ approaches.

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