Diversity of Yam (<i>Dioscorea spp</i>.) Populations in South Western Region of Cameroon

Abstract

Yams are Dioscoreaceae grown in the tropics and sub-tropics and used as food and for related pharmaceutical properties. The South Western Region of Cameroon is a major yam producing zone. This study which evaluates morphological variability between ten linguistically different yam types grown in South Western Cameroon will serve as a necessary step for subsequent genetic study of the species. The yams, collected from nine sites, were planted in a completely randomized design in four locations. Analysis of data on nine morphological vines traits reveals that, the yam types constituted five main clusters. Cluster 1 with 61.3% similarity consists of five accessions of D. rotundata-Ikom, Calabar, White, Agar and Igbo yams. This cluster has three subgroups with 84.9% similarity. Cluster 2 consists of Yellow yam (D. cayenensis) with 48.5% similarity to members of Cluster 1. Ghana Water yam and Swệt yam constitute Cluster 3 with 83.4% similarity while Sugar yam and Water yam constitute the 4th and 5th clusters respectively. The ten yam types are actually five cultigens-rotundata, rotundatacayenensis complex, cayenensis, dumetorum and alata; and the significant variability (P<0.05) observed with respect to the morphological characters evaluated may be the basis for the linguistic polymorphism noticed in the naming of the different yam types. Although genetic analysis is recommended to determine firm similarities, the establishment of clear links remains problematic because of the high hybridisation noticed among members of the Dioscoreaceae; and considering that yams types were introduced in the zone from different lands over many centuries.

Distribution, Diversity and Potential Production of Yams (&lt;i&gt;Dioscorea&lt;/i&gt; spp.) in Sheko District, Southwest Ethiopia

“…They are staple foods in many parts of the tropics, being the source of most of the daily carbohydrate intake for large populations [9,13]. These carbohydrates are mostly starches found in storage organs, which may be enlarged roots, corms, rhizomes, or tubers.…”

“…These carbohydrates are mostly starches found in storage organs, which may be enlarged roots, corms, rhizomes, or tubers. Many types of yams are grown as traditional foods or are adapted to unique ecosystems and are of little importance to world food production [13]. The edible yams (Dioscorea alata, Dioscorea bulbifera and Dioscorea abyssinica) were important to the agriculture and food security of the in the community of the Sheko district even to other woreda of the Bench Maji Zone and many countries of the world that accounted the overall component of the diet for 2.2 billion people in developing countries [7,8].Among the finding of yams (Dioscorea spp.)…”

“…The main production of yam is in the savannah region of West Africa, where more than 90% of the crop is grown. Unlike the other root and tuber crops the white and yellow yam (Dioscorea rotundata and Dioscorea cayenensis [esculenta], respectively) are thought to be indigenous to West Africa, whereas the water yam (Dioscorea alata) is thought to have originated in Southeast Asia [20,14,13].Yam is a deeply rooted, climbing, dioecious perennial vine with distinctly veined cordate (heart-shaped) leaves. The tubers are coarse, dry to mealy, tender, crisp, and too mushy and are equivalent in food value to the potato.…”

Multi-Trait Selection Index for Superior Agronomic and Tuber Quality Traits in Bush Yam (Dioscorea praehensilis Benth.)

“…Several studies have been carried out on yam using morphological descriptors [6][7][8][9]. Many authors [10][11][12][13] have reported the effectiveness of morphological markers in assessing genetic diversity in D. alata.…”

Identification of diagnostic KASP‐SNP markers for routine breeding activities in yam (Dioscorea spp.)

“…Yam ( Dioscorea spp.) is a multi‐species monocotyledonous tuber crop predominantly cultivated in the tropical regions of Africa, Southeast Asia, and Latin America (Azeteh et al., 2019; Darkwa, Olasanmi, et al., 2020; Oben et al., 2016). Dioscorea encompasses about 600 species (Burkill, 1960), of which only 11 are widely cultivated species (Darkwa, Olasanmi, et al., 2020).…”