Nuña beans are a type of common bean ( Phaseolus vulgaris L.) native to the Andean region of South America that possess the unusual property of popping when exposed to heat ( National Research Council, 1989 ). Popped nuñas are a snack food similar
Nuñas are a type of common bean (Phaseolus vulgaris) that possess the unusual characteristic of popping or expanding their cotyledonary tissue when heated. Numerous landraces of nuña beans were domesticated in the Andean region of South America (Peru, Bolivia, and Ecuador) and have been grown and consumed in this region since antiquity. The practical consideration in the domestication of nuñas in the high Andes was likely due to the greater energy efficiency in cooking toasted vs. boiled seeds.The Phaseolus germplasm bank at CIAT (Centro Internacional de Agricultura Tropical) has developed a core collection of Andean beans that includes numerous nuña landraces. Based on the wide range of phaseolin types observed among nuña landraces, it has been hypothesized that nuñas may represent a greater source of genetic diversity compared to other landraces and cultivars of common bean. Eighty nuña accessions and 120 nonpopping common bean accessions were randomly sampled from the CIAT Andean germplasm core collection. The 200 accessions were characterized for 140 mapped RAPD markers. The objectives of our research were to 1) understand the genetic structure of nuña bean accessions relative to other Andean common beans, and 2) to measure the genetic distance and genetic diversity between nuña and other Andean bean populations.
Quechua farmers have cultivated mashua (Tropaeolum tuberosum Ruiz & Pavon) and other tuber crops for thousands of years. The practice of trading seed tubers may have contributed to dispersal of viral diseases, such as the tropaeolum mosaic virus (TropMV). We surveyed 17 accessions of mashua collected from Quechua farmers in the provinces of Cuzco and Ayacucho, Peru. Most cross-reacted with the TropMV antibody and showed viral disease symptoms. Significant differences were observed between accessions from Cuzco and Ayacucho, with respect to virus infection and tuber yield under greenhouse conditions. Of the accessions from Cuzco, 87% displayed viral symptoms, while only 22% from Ayacucho showed symptoms. Fewer tubers from Cuzco generated mature plants. In turn, those mature plants produced lower tuber yields. The practice of trading seed tubers may be advantageous for promoting crop diversity but can be harmful when diseased seed tubers are being traded. A program to generate and distribute virus-free seed tubers among Andean farmers would contribute to higher crop yields while preserving local customs and crop diversity.
A knowledge of the relative proportion of additive and nonadditive genetic variances for complex traits in a population forms a basis for studying trait inheritance and can be used as a tool in plant breeding. A North Carolina Design II mating scheme was used to determine the inheritance of cooking time, protein and tannin content, and water absorption among 16 genotypes of dry bean (Phaseolus vulgaris L.) representative of the Andean Center of Domestication. Heritability and the degree of dominance for the traits were also calculated to provide guidelines for adopting breeding strategies for cultivar development. Thirty-two progeny resulted from the matings and these were assigned to two sets of 16 progeny each. Variances due to general combining ability (GCA) and specific combining ability (SCA) were significant for the traits. The GCA was larger in all cases. Narrow-sense heritability for protein, tannin, water absorption, and cooking time averaged 0.88, 0.91, 0.77, and 0.90, respectively. Degree of dominance estimates indicted that the traits were governed by genes with partial dominance except, in one case, tannin had a degree of dominance value of zero, indicating no dominance. The phenotypic correlation (-0.82) between water absorption and cooking time justifies using the water absorption trait as an indirect selection method for cooking time. With regard to parent selection in crosses, significant differences between GCA females and GCA males suggested cytoplasmic influences on trait expression. Hence, the way a parent is used in a cross (i.e., as female or male) will offset trait segregation. Using fast-cooking bean cultivars in conjunction with fuel-efficient cooking methods may be the best strategy to conserve fuelwood and help reduce the rate of deforestation in East and Central Africa.
/proceedingpapers/15 . [accessed 2 Dec 2022] Ehlenfeldt, MK Polashock, JJ Rowland, LJ Ogden, E Luteyn, JL. 2022 Fertile intersectional hybrids of 4 x Andean blueberry ( Vaccinium meridionale ) and 2 x lingonberry ( V. vitis-idaea ) HortScience. 57
Vaccinium meridionale (section Pyxothamnus), a tetraploid species native to higher-altitude locations in Jamaica, Colombia, and Venezuela, is of interest to Vaccinium breeders for its profuse, concentrated flowering, vigor, and monopodial plant structure, all of which may be useful in breeding for mechanical harvest in blueberry. In this study, tetraploid V. meridionale was successfully hybridized as both female and male with 2x Vaccinium vitis-idaea (section Vitis-idaea, lingonberry). The resultant F1 hybrids with lingonberry were both 3x and 4x, respectively. These hybrids were intermediate in morphology and notably vigorous. Most appear to be evergreen, with small, red-colored fruit. The 4x F1 hybrids displayed good fertility as females in backcrosses to both lingonberry and V. meridionale. Pollen production and quality were evaluated as an indicator of male fertility. Most clones had good pollen shed and high frequencies of well-formed tetrads. The overall fertility suggests that these hybrids, despite being derived from intersectional crosses, might be conventionally used for breeding without substantial difficulty.
) and from southern Peru to northwestern Argentina (Andean gene pool) ( Gepts et al., 1986 ; Khairallah et al., 1990 ; Koenig and Gepts, 1989 ). After the initial domestication phase, the common bean spread between Mesoamerica and South America and
Common bean (2n = 2x = 22) is the most important edible food legume for direct human consumption in Europe and in the world as it represents a valuable source of proteins, vitamins, fiber, and minerals ( Broughton et al., 2003 ). The Andean region