Taro and new cocoyam are root and leaf crops commonly grown in tropical to warm temperate regions. In Togo, they are neglected and underutilised. Here we report the genetic diversity of 26 accessions of taro and 101 accessions of new cocoyam. Analysis of simple sequence repeats revealed low polymorphic information content of 0.43 and 0.25 in taro and new cocoyam, respectively. PCA scatterplots and Neighbour Joining dendrograms based on the SSR data clustered accessions into groups that more-or-less correspond to morphological diversity in both species. AMOVA within and between morphological groups revealed greater variances within groups than between. This indicates weak genetic differentiation between morphological groups, particularly for taro. Genetic diversity was greater among taro cultivars. Taro has a longer history of introduction and dispersal in Africa, and has had more opportunity for multiple introduction and local cultivar development. Different strategies are suggested for future development of these crops in Togo and Africa. For taro, further studies of existing diversity and recent experimental introduction, has spread widely in Africa with little genetic diversity. For this crop, international collaboration is needed to clarify taxonomy,  and to introduced further cultivars for evaluation under local conditions in Africa.

Cowpea [Vigna unguiculata (L.) Walp.] is a crop with significant agronomic and nutritional value. In Togo, the crop is very appreciated by local people. It is the third food habit in Togo after maize and rice. However, several accessions of cowpea cultivated in Togo are now prone to extinction, creating a risk of genetic erosion. It is therefore urgent to assess the genetic diversity of accessions in order to set up a good conservation program. To achieve this, genetic diversity and phylogenetic relationships among 70 accessions of cowpea collected in the five (5) administrative regions of Togo were assessed using Simple Sequence Repeat (SSR) molecular markers. The twenty-eight SSR primers used in this study generated a total of 164 alleles with an average of 5.82 alleles per locus. Polymorphic Information Content (PIC) values ranged from 0.20 to 0.89 with an average value of 0.58. Population structure analysis using model-based revealed that the cowpea germplasm was grouped into two subpopulations. The analysis of molecular variance (AMOVA) revealed that 98% of genetic variation existed among accessions within regions. The fixation index (Fst) value, which was 0.069 was low, indicating relatively low population differentiation. The phylogenetic analysis grouped the 70 accessions into two main groups that can be further divided into four groups independent of their origins. This study provides a foundation for a Togolese cowpea germplasm conservation program and can serve for the selection of parental material for further studies aimed at the genetic improvement of local germplasm.

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The investigation of the nutritional value of Neglected and Underutilized Crop Species is essential for their valorization. This global systematic review aimed at investigating the nutritional value of tigernut to highlight the importance of the species in the fight against malnutrition. Extensive searches were carried out through three databases (ScienceDirect, Google Scholar, and African Journal Online) from March to April 2021, and studies were screened and extracted using the established systematic review methods. A total of 36 papers from Africa, America, Asia, and Europe met the inclusion criteria. Thematic synthesis was used to synthesize data, and findings were presented under three framework aspects (biochemical, mineral composition, and vitamin content). About 63.88% of the papers included in this global review were published from 2010 to 2020. The highest number of papers (n = 14) was recorded between 2015 and 2020, and most of the publications were from Europe (n = 13). The review showed that tigernut contained alkaloids, cyanogenic glycosides, resins, tannins, sterols, and saponins. It was very rich in potassium (K), followed by phosphorus (P), magnesium (Mg), calcium (Ca) sodium (Na), iron (Fe), zinc (Zn), copper (Cu), and vitamins A, B, C, D, and E. The review has also revealed that biochemical composition and vitamin content of tigernut depend on its geographical origin. Overall, the results highlighted the nutritional values of tigernut. Its valorization in foodstuffs could increase the profitability of this crop and contribute to the fight against malnutrition in Africa.

Food security relies mainly on a few major crop such as wheat, maize, rice and yam. Many of the cultivated plant such as Cyperus exculentus are still considered invasive plants and are neglected and underutilized. In the perspective to valorization of the species, this systematic review aimed at identifying the biology, production constraints and uses of tigernut for future research directions. Extensive searches were carried out and studies were screened and extracted using established systematic review methods. A total of 175 papers met the inclusion criteria. Approximately 52% and 21.71% of the studies were undertaken in Europe and Africa respectively. Most of the papers reviewed for the study were published between [2010-2015[. The review highlighted the critical research gaps in genetic diversity using SSR makers and evolutionary biology. Further, production constraints and solution approaches for the promotion of the species were the other gaps identified in the reviewed studies. Production constraints were specifically related to the insufficient mineral fertilizers and difficult in harvesting. Tigernut is used in more fields such as food, medicinal, cosmetic, biofuel and fishing and fish breeding. Such investigations would help in decision-making and elaboration of breeding strategies, and advancing steps towards sustainable use of the species.