Genetic diversity of two Indian common bean germplasm collections based on morphological and microsatellite markers

Abstract

India is the second most populous nation in the world after China, and its plant genetic resources are an important basis for crop improvement to meet human population needs. An important legume in the diet of the Indian population is common bean (Phaseolus vulgaris L.). Common beans are one of the many important legumes grown in India, but unlike others, its centre of origin is not in Asia but in the Americas. The objective of this study was to evaluate two collections of Indian common beans: one for an internationally available collection of Food and Agriculture Organization (FAO)-protected accessions and one from the north-western Himalayan region. In total, 149 Indian landraces were evaluated with a total of 24 microsatellites across the two collections, and these represented all common bean-growing states of India. A population structure analysis was used to find groups in each collection, and this was compared across the collections. The genetic analysis of the two sets of Indian accessions with neighbour-joining trees and principal component analysis categorized the landraces into Andean and Mesoamerican gene pool groups. The Andean genotypes dominated the north-western Himalayan collection while the FAO-protected accessions were predominantly Mesoamerican. The Indian subcontinent can be considered as a region of high bean diversity; however, very little introgression was observed between the gene pools in both the germplasm sets. Gene pool identity was further substantiated by the comparison of seed traits, particularly seed size. The role of the landraces in plant breeding programmes is discussed.

Legume Crops Phylogeny and Genetic Diversity for Science and Breeding

“…The primary centers of origin for the Phaseolus cultigens are in the New World; however, for each crop there has been a different spread outside the original range, with greater spread for common bean than for any of the other species. Common bean has secondary centers of diversity in Africa, Brazil, the Caribbean, China, Europe and India Asfaw et al, 2009;Blair et al, 2010;Sharma et al, 2013), while tepary bean has spread very little outside its original range in northern Mexico, spreading only to parts of Central America (Blair et al, 2012a). Similarly, scarlet runner beans have spread ancestrally from Central America only to northern South America, while year-long beans for the most part remain in the Guatemalan highlands.…”

“…& W.C. Greg. In addition to above-mentioned cultivars, several other elite lines have been bred using wild relatives from across the world, and these elite lines possess resistances to different diseases and pests in groundnut (see Sharma et al, 2013).…”

Conserving maize in gene banks: Changes in genetic diversity revealed by morphological and SSR markers

“…In numerous diversity studies, application of SSRs was appropriate for grouping accessions according to their geographical origin, e.g. in bean (Sharma et al, 2013), tomato, (Mercati et al, 2015), maize (Cömertpay et al, 2012). Based on SSR markers, maize landraces from the same small area were in the group with genetically similar accessions (Figure 4).…”

Common Bean

“…The presence of secondary centers of diversifi cation in Spain, Turkey, and Ethiopia (Harlan 1971 ;Santalla et al 2002 ;Ocampo et al 2005 ) is controversial (Kami et al 1995 ). The addition to the secondary centers of common bean diversity in Asia has been made in recent analysis of Chinese and Indian beans (Zhang et al 2008 ;Sharma et al 2013 ).…”