Assessment of physicochemical diversity in fruit of Mauritanian date palm (Phoenix dactylifera L.) cultivars

Abstract

Date palm is an important food and economical crop in Mauritania. Date palm cultivars show great diversity in fruit morphological characteristics in the 'Adrar' region of Mauritania. Fruits of twenty-eight date palm cultivars were collected at Tamar stage, from three different oasis of the 'Adrar' region in 2010 and 2011 and their physical and chemical diversity was assessed by using different data analysis techniques. Analysis of variance revealed statistically significant differences between cultivars for the 13 examined characters indicating the high diversity in the physicochemical properties of their fruit. Duncan's multiple range test allowed clustering of cultivars into different groups depending on the parameters. Principal component analysis and cluster dendrogram performed on the basis of studied parameters showed a distribution of date palm cultivars independently of their oasis origin and a continuous variation in their fruit physical and chemical traits. Date varieties under 'Ahmar' denomination showed diverse fruit properties. Characters that can discriminate the best cultivars were fruit water content, reducing sugars, total sugars, non-reducing sugars, ashes, calcium and magnesium contents. Results also give evidence of the existence of common date varieties such as 'Sekanni', 'Bou seker', 'Sembahmoud', 'Tenwazidi' and 'Sel medina' with fruit properties matching or even higher than the elite cultivar 'Ahmar'. The possible use of date palm fruits characteristics either in the description of local date palm germplasm or the valorisation of common date varieties are discussed.