Welcome to the first project in our Orphan Species Initiative (OSI). The OSI was established to help less privileged countries gain access to high-quality reference genomes for species of importance. In many cases, these will be agriculturally relevant species, but OSI is not limited to that scope. For example, an endangered animal or plant species with cultural importance or with no genomics funding or resources could also be considered. In this first project, we completed a chromosome-scale genome assembly for Moringa (Moringa oleifera).

Moringa (Moringa oleifera) is a perennial shrubby tree originating from the foothills of the Himalayas in North-Western India and now widely distributed and cultivated across tropical and sub-tropical areas in Asia, Africa, and Latin America. Moringa is an important, multi-purpose, nutrient-dense tree used as food, fodder, and medicine as a part of tropical and semi-tropical agroforestry landscapes. It is a fast growing, easily manageable tree with abundant production of edible leaves, flowers, and fruits. The leaves are 27% protein by dry weight with essential amino acids and are rich in vitamins C, provitamin A, K, beta-carotene, and minerals: calcium, iron, magnesium, manganese, and phosphorus with high dietary fiber. The leaves also contain a very high number of antioxidants (polyphenol) and anti-inflammatory agents (isothiocyanate) with potential health benefits. Due to its agro-economic potential and high nutrient contents like iron, it is considered as an important potential source to combat malnutrition, especially for women and children in developing countries. Thus, Moringa was prioritized by Allen Van Deynze (UC Davis) and the African Orphan Crops Consortium to generate genomic resources and to develop a breeding program based on this information.

Moringa: an important, multi-purpose, nutrient-dense tree used as food, fodder, and medicine

Allen Van Deynze, Director of Research Seed Biotechnology Center, UC Davis

A high-quality, chromosome-scale genome assembly was generated using nanopore long reads and scaffolded using Dovetail Omni-C proximity ligation technology.  This genome assembly is a critical first step for downstream genetic analyses of Moringa and will enable hypothesis-driven breeding. An analysis of genetic diversity in the ICRAF’s Moringa gene bank collection (~ 400 accessions) using DArT-SNP markers indicated that African material comprised a narrow gene pool. Phenotypic evaluation and genotyping will commence in 2020 and genome-wide association approaches will be used to assess trait-linked markers and to evaluate the potential for marker-assisted or genomic selection to improve the species for beneficial traits such as leaf and seed production, seed oil yield, foliar nutritional content.