La diversité génétique des bananiers plantains cultivés dans la zone Ouest de la Région des Plateaux au Togo

Le bananier représente l’une des cultures les plus importantes dans le monde. Au Togo, la culture de bananiers plantains se fait surtout dans la Région des Plateaux à l’Ouest dans de petites exploitations agricoles ; ce qui a entrainé une faible productivité. Cependant, les variétés de bananiers plantains cultivées ne sont pas bien connues. Un inventaire a été entrepris dans le but de dénombrer les variétés de bananiers plantains cultivés grâce à des paramètres agromorphologiques et aussi de montrer l’intérêt que suscite la valorisation de la culture de cette plante. Au terme de cette étude, cinq (5) variétés de bananiers plantains ont été recensées. La variété ‘Apim’ est la plus productive suivie de la variété ‘Abladzo’. Contrairement aux autres, la variété ‘Taévé’ produit 2 régimes par pied au lieu d’un régime. Le cycle végétatif des bananiers plantains varie de 11 à 15 mois sauf pour la variété ‘Apim’ qui est de 18 mois. Des études de propagation rapide doivent être envisagées pour la sélection des variétés hautement performantes et la production massive du plantain pour les populations locales.© 2013 International Formulae Group. All rights reserved.Mots clés : Togo, bananier plantain, diversité génétique

Saffron, an alternative crop for sustainable agricultural systems. A review

Saffron (Crocus sativus L.) is an autumnal flowering geophite whose dried stigmas, well known for their aromatic and colouring power, have been used since immemorial time as a spice in human nutrition, for medicinal purposes and as a dye. Many doubts remain on its origin; it was probably selected and domesticated in Crete during the Late Bronze Age. Saffron is an autotriploid geophyte species, self- and out-sterile and mostly male-sterile and therefore unable to produce seed, that reproduces by means of corms. Furthermore, it has a reverse biological cycle compared with the majority of cultivated and spontaneous plants: flowering first in October-November, then vegetative development until May, which means that the vegetative development is not directly important for production of stigmas, but for the production of new corms. Due to its unique biological, physiological and agronomic traits, saffron is able to exploit marginal land and to be included in low-input cropping systems, representing an alternative viable crop for sustainable agriculture. Notwithstanding this great potential and the considerable increase in new generation consumer demand for saffron, the future of the plant is still uncertain. Indeed, the main obstacles to saffron production are: (1) the limited areas of cultivation in countries where it is traditionally grown, (2) the great amount of sophisticated spice, (3) management techniques executed by hand, and (4) the very high price of the spice. Here we review the main biological, genetic and ecological traits associated with agronomic management techniques of saffron in relation to environmental conditions. Colour, taste and aroma are the essential features on which the quality of saffron stigmas is founded. In turn, these aspects are strictly connected with the biomolecular composition of the stigmas, namely, the carotenoids and their derivatives. With this in mind, the biosynthetic pathway that leads to the formation of saffron secondary metabolites and their abundance in the spice is presented, together with the biomedical properties commonly associated with saffron. Furthermore, a detailed overview of the more recent instrumental methods to assess the quality of saffron, strictly from a chemical point of view, will be discussed