Morphological diversity of the agroforestry species Moringa oleifera Lam. as related to ecological conditions and farmers' management practices in Benin (West Africa)

摘要

Moringa oleifera Lam. is an agroforestry species grown for its various uses. Despite its great socio-economic importance, the species is still not well exploited and considered as a neglected and underutilised species. This study aimed at identifying the morphotypes of M. oleifera and assessing how they were related to climatic conditions and farmers' management practices. The study was conducted in 30 districts spanning the three biogeographical zones and 11 major sociocultural groups of Benin. Twenty-four morphological traits describing the trunk, crown, leaf, leaflet, pod, and seed were collected on 810 adult individuals randomly selected within districts. Linear mixed-effects models were used to investigate variation in morphological traits of M. oleifera according to biogeographical zones and management practices. Then, hierarchical clustering and canonical discriminant analyses were performed on morphological traits to identify and characterise the morphotypes of M. oleifera. Results revealed great variability in morphological traits of M. oleifera according to climate gradient and farmers' management practices. Four morphotypes were identified with five morphological traits (number of tertiary branches, leaf maximum width, leaf length, pod length and dry pod weight) as the most discriminant. According to the most harvested organs (leaves and seeds), the best morphotype was from the sudano-guinean zone. These findings are crucial for selection and breeding programs and for the improvement of domestication strategies of the species. This will support efficiently the implementation of more environmental and socioeconomic-friendly promotion of the species through its cultivation and use in Benin, as well as in West Africa. (C) 2019 SAAB. Published by Elsevier B.V. All rights reserved.