In the Caribbean, three of the five domesticated Capsicum species are cultivated: C. annuum (sweet peppers), C. frutescens (bird peppers), and C. chinense (aromatic hot peppers). However, C. chinense is commercially the most important throughout the region (DeWitt and Bosland, 2009). South America is considered the center of origin and highest diversity of C. chinense (Eshbaugh et al., 1983; Pickersgill, 1969). Early geographical dispersion into the Caribbean may have occurred with the migrations of native Indians across the islands as well as through avian-aided dispersal (Reid, 2009; Tewksbury and Nabhan, 2001). Two points of entry into the Caribbean have been proposed (Moses and Umaharan, 2012): 1) from South America to Trinidad [across the land connection mentioned by Kenny (2008) that once existed between the two land masses] with subsequent movement across the other islands of the Southern Caribbean (Lesser Antilles); and 2) from Central America to the Northern Caribbean islands (Greater Antilles, the Bahamas) (Fig. 1).
It is likely that through anthropogenic influences and long separation from the South American mainland, new varieties have arisen displaying useful plant adaptations and desirable fruit traits. Recent molecular studies revealed the importance of the Caribbean as an important region of this species’ diversification (Moses and Umaharan, 2012) as well as a region containing some of the most aromatic pungent peppers in the world (Bosland et al., 2012; Gibbs and O’Garro, 2004; Holder, 2008). As a known region of diversity for C. chinense, the Caribbean varieties could be potentially useful sources of variation in agronomically important traits, e.g., early flowering and fruiting, desired fruit quality traits, suitable plant growth habit, and disease resistance, among others.
The Caribbean is well known for its diverse range of pepper fruit forms and varied consumer preferences as a result of their varied cuisines. With the spread of Caribbean people and their cuisines to different parts of the world, aromatic hot peppers have fueled growing public interest in their cultivation for diverse commercial uses, e.g., the food industry (fresh consumption as a vegetable and processed products such as pepper mash, sauces, salsas, pickles, jams, and jellies), the defense industry (repellants, military use), pharmaceutical and health industries, and as ornamentals (Bosland and Votava, 2003; Cichewicz and Thorpe, 1996; DeWitt and Gerlach, 1990; Elkins, 1997; Jancsó et al., 1984; Lo et al., 2005). There has therefore been global increase in cultivation and parallel research and development to help meet the growing industry demands.
In the Caribbean, although many varieties exist, few are formally known and commercially exploited. Many others remain as unstabilized landraces showing inconsistent fruit quality traits and yield. Consequently, foreign hybrids, capable of higher yields and more consistent fruit quality, are rapidly replacing local varieties and this contributes to ongoing decline in diversity available to regional breeders. This decline, coupled with limited varieties currently available for use, also restricts the ability of the regional pepper industry to exploit development of diverse pepper products (Bharath, 2012). Systematic replacement of local varieties could facilitate complete loss of unique, valuable Caribbean germplasm and prevent diversification of the value-added pepper product industry in the region with possible considerable economic and social impact.
Jarret and Berke (2008) were the first to describe the morphological variation for fruit characteristics in an extensive USDA/ARS global C. chinense collection (330 accessions). However, only 14 accessions representing three Caribbean islands [Cuba (one), Puerto Rico (10), Trinidad (three)] were evaluated. The Caribbean Agricultural Research and Development Institute (CARDI) has also done some morphological characterization of regional varieties, but these were limited to eight to 10 landraces primarily from Trinidad, Guyana, and Barbados (CARDI, 2002). Most of the Caribbean’s fruit diversity has therefore remained underrepresented in global and regional collections and consequently understudied and underdocumented even within the region itself (Bharath, 2012). There was therefore an urgent need to systematically document and characterize the region’s current diversity and to place this diversity into regional context. This will serve as a necessary precursor to envisioned regional pepper breeding and improvement programs.
This present study investigated variation in fruit morphology in a Caribbean C. chinense germplasm collection held at The University of the West Indies, Trinidad (UWI). This germplasm represents material collected from three major regions of diversity: Central America, the Caribbean Basin (northern and southern territories), and South America with representatives from geographic subgroups (Fig. 2). Using the international Capsicum descriptor guide [International Plant Genetic Resources Institute et al. (IPGRI), 1995] to morphologically characterize the accessions, this study aimed to determine 1) the level of interaccession variation across 13 fruit descriptors; 2) any links between quantitative and qualitative fruit traits; and 3) the level of fruit morphological dissimilarity among accessions based on their geographic origins.
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