Seed and seedling morphological characterization of Jatropha mollissima (Pohl) Baill. (Euphorbiaceae): a potential species with multiple uses

ABSTRACT The seeds and seedlings morphological differentiation is a challenge in the early stages of plant growth. This study aims to describe the physical and morphological characteristics of seeds and seedlings of Jatropha mollissima to delimit differences between other species from the same genus. The seeds were placed to germinate for morphological description and their physical characteristics were measured. The J. mollissima presented a 1000-seed weight of 332 g, 3,008 seeds per kilogram, 6.7% of moisture, 1.29 cm length, 0.84 cm width, and 0.66 cm thickness. We verified that the seeds are oval in shape; their colour is dark brown, greyish or mixed colour; they have visible raphe and hilum, and caruncle with beige coloration. The endosperm is oleaginous and involves the embryo with foliaceous and spatulate cotyledons. The embryo is axial, and the hypocotyl-radicle axis has a short cylindrical shape. Germination is epigeal and phanerocotyledonary; leaves have dimorphism and serrated margins with simple trichomes; and their apex is cuspidate or attenuated. Our research demonstrates that it is possible to differentiate J. mollissima from other species of the same genus through morphological characteristics. Therefore, this work contributes to the correct identification of the species, laboratory analysis, and field recognition.