Messias Firmino de Queiroz

Crescimento e fenologia de espécies de Jatropha durante a estação chuvosa

Jatropha curcas L., Jatropha mollissima (Pohl) Baill and Jatropha gossypiifolia L. are Euphorbiaceae with potential for biodiesel production and use in pharmaceutical and cosmetic industries. The aim of this study was to evaluate these species in terms of growth and phenology in a field experiment. In this study an experimental design of randomized blocks was adopted. The experimental plot had 18 plants and a useful plot area of 15 m2. In the phenological studies of plants the following phases were considered: establishment/vegetative growth, flowering, fruiting and ripening/harvest. The phenological stages of the species differed chronologically. Jatropha mollissima outgrew the others in plant height, while Jatropha curcas outgrew the others in stem diameter. The highest relative growth rates in plant height occurred during vegetative growth, with the highest values being recorded in Jatropha mollissima, while the greatest relative growth rates also in vegetative growth were recorded in Jatropha curcas. The lowest relative growth rates in plant height and stem diameter of the studied species coincided with the reproductive phases.