Domestication Syndrome in Caimito (Chrysophyllum cainito L.): Fruit and Seed Characteristics

• Published in: Economic botany 2010-06, Vol.64 (2), p.161-175
• Main Authors: Parker, Ingrid M, Lopez, Isis, Petersen, Jennifer J, Anaya, Natalia, Cubilla-Rios, Luis, Potter, Daniel
• Format: Article
• Language: English
• Subjects: artificial selection; Biomedical and Life Sciences; Chrysophyllum cainito; cultivars; Cultivation; Domestication; domestication syndrome; Exocarp; fruit crops; Fruit cultivation; Fruit trees; Fruits; fruits (plant anatomy); home gardens; Leaves; Life Sciences; pericarp; phenolic compounds; Phenols; Phenotypic traits; phytochemicals; Plant Anatomy/Development; Plant domestication; Plant Ecology; Plant Physiology; Plant Sciences; Plant Systematics/Taxonomy/Biogeography; Plants; seed productivity; Seeds; selection criteria; Statistical variance; Sugar; sugar content; Sugars; titratable acidity; Tree crops; Trees; tropical and subtropical fruits; Tropical environments; Tropical forests; weight; wild plants
• ISSN: 0013-0001; 1874-9364
• DOI: 10.1007/s12231-010-9121-4

The process of domestication is understudied and poorly known for many tropical fruit tree crops. The star apple or caimito tree (Chrysophyllum cainito L., Sapotaceae) is cultivated throughout the New World tropics for its edible fruits. We studied this species in central Panama, where it grows wild in tropical moist forests and is also commonly cultivated in backyard gardens. Using fruits collected over two harvest seasons, we tested the hypothesis that cultivated individuals of C. cainito show distinctive fruit and seed characteristics associated with domestication relative to wild types. We found that cultivated fruits were significantly and substantially larger and allocated more to pulp and less to exocarp than wild fruits. The pulp of cultivated fruits was less acidic; also, the pulp had lower concentrations of phenolics and higher concentrations of sugar. The seeds were larger and more numerous and were less defended with phenolics in cultivated than in wild fruits. Discriminant Analysis showed that, among the many significant differences, fruit size and sugar concentration drove the great majority of the variance distinguishing wild from cultivated classes. Variance of pulp phenolics among individuals was significantly higher among wild trees than among cultivated trees, while variance of fruit mass and seed number was significantly higher among cultivated trees. Most traits showed strong correlations between years. Overall, we found a clear signature of a domestication syndrome in the fruits of cultivated caimito in Panama. El proceso de domesticación de muchos árboles frutales tropicales es poco estudiado y entendido. El caimito (Chrysophyllum cainito L., Sapotaceae) es cultivado, por su fruto comestible, en todas las regiones tropicales de América. Hemos estudiado esta especie en Panamá central, donde crece en huertos caseros y en poblaciones silvestres del bosque húmedo tropical. Usando frutos colectados en dos años de cosecha, probamos la hipótesis de que las semillas y los frutos de individuos cultivados e individuos silvestres de C. cainito tienen características distintas debido a la domesticación. Encontramos que los frutos de los individuos cultivados fueron significativa y sustancialmente más grandes, con mayor cantidad de pulpa y menos exocarpo que los frutos de individuos silvestres. La pulpa de la fruta de los individuos cultivados fue menos ácida, con menor concentración de compuestos fenólicos y alta concentración de azúcares. Las s