Participatory evaluation of Guinea yam (Dioscorea cayenensis Lam.–D. rotundata Poir. complex) landraces from Benin and agro-morphological characterization of cultivars tolerant to drought, high soil moisture and chips storage insects

Guinea yam (Dioscorea cayenensis Lam.–D. rotundata Poir. complex) is an important tuber crop that highly contributes to food security and poverty alleviation in Benin. However, its production is seriously affected by many biotic and abiotic constraints which could be overcame by concentrating the production on resistant or tolerant cultivars. In order to identify such cultivars that are known to exist in Benin traditional agriculture, 51 villages were randomly selected throughout the production zones and surveyed. Out of the 426 cultivars (subject to synonymy) evaluated using participatory approach and 13 agronomic, culinary, and technological traits, 25, 47, 49, 64 and 64 cultivars respectively tolerant to poor soils, nematodes, high soil moisture (adaptability to lowland), drought and chips (peeled and dried tuber) storage insects were, among others, identified. These pools of cultivars could serve in breeding program or be directly used in varietal exchanges towards the zones of interests. The agromorphological characterisation conducted per pool of performing cultivars revealed the existence of many duplicates that should be clarified with the use of molecular markers. Flowering, sex and intensity of flowering of the different cultivars were analysed and revealed a low rate (11.68 %) of non-floriferous plants, a high rate (61.03 %) of plants with low intensity of flowering and five types of male inflorescences indicating a hypothetical evolution towards the suppression of flowering with the cultivated yams.