Effects of Diverse Fertilizations on Rhizome Yields, their Essential Oil Content and its Phytochemical Composition in Ginger (Zingiber officinale Roscoe) Cultivated in the Southern of Benin Republic

Zingiber officinale Roscoe (ginger) is widely used as a spice or medicinal plant in folk and traditional medicines. Despite its importance in the daily life of human beings in Benin, ginger has paid to date little attention in research activities, particularly those concerning the needed agricultural practices to enhance productivity and maintain the environmental balance. The present study reported therefore the first preliminary surveys in agronomical practices and their relationships to rhizome yields and their phytochemical quality in ginger cultivated in Benin. Two genotypes from Nigeria were surveyed through a randomized complete block design with four replications at two locations over two years in Benin. Rhizome phytochemical composition was analyzed by gas chromatography–mass spectrometry (GC-MS). The major compounds (>3%) in rhizome essential oil were α- zingiberene (37.62%), β- pinene (15.51%), β- sesquiphellandrene (8.27%), δ- farnesene (7.75%), geranial (5.44%), α- curcumene (5.29%), α- pinene (3.84%) and limonene (3.22%). Analysis of means in ANOVA showed divergences due to genotype, treatment and/or their interactions. Those differences depended too on the character under observation. Kruskal-Wallis non-parametric test permitted to discovery the best treatment or genotype according to the observed trait. Principal component analysis allowed to analyze the relative importance of each character to the variation of morpho-agronomic and quality traits. These researches need to be completed by collecting more accessions from farmers in West Africa. They will be evaluated under a panel of climate areas. The number of treatments shall increase by mixing different doses of organic (biological) and inorganic (chemical) fertilizers and analyzing their relative roles in growing productivity and maintaining stable local environmental balances. Such research will contribute to study further genetic parameters for morpho-agronomic and quality trait expressions, and will therefore facilitate breeding progress in the crop.