Morfologia de frutos, sementes, plântulas e plantas jovens de três espécies de Solanum l. (solanaceae).

Abstract

The objective of this research was to characterize morphometrically morphological aspects of fruits and seeds, plants and young plants of three species of Solanum L. The genus is the largest and most diversified of Solanaceae Juss. It has a large number of species that infest agricultural areas, gardens and vacant lots, among other types of agrosystems, such as Solanum americanum Mill. (maria-pretinha), S. stramoniifolium Jacq (jurubeba) and S. crinitum Lam (lobeira da mata). The morphometry of the structures mentioned above and the aspects related to germination can help the development of efficient techniques for the management and control of these communities. The morphometric characterization was performed using 100 fruits and 100 seeds from four matrices collected in four municipalities in the metropolitan region of Belém, in anthropized areas. Of the fruits, the following were recorded: general morphology, classification, color, texture, consistency of the epicarp, diameter, weight and number of seeds per fruit. The seeds were analyzed externally: shape and border; integument; hilum and micropyle; internally: endosperm and the embryo. For the analysis of the ornamentation of the seed forehead, scanning electron microscopy (SEM) techniques were performed. The fruits are polyspermic, fleshy, berry-type, dehiscent, consisting of one or two locules with the seeds attached to the axial placenta, calves with five lobes on the end, green when immature, purple and red glabrous in S. americanum Mill and S. stramoniifolium Jacq. and pulbescent greens in S. crinitum Lam, when ripe, have averages of 17.93 mm in length, 18.39 mm in diameter, mass of 17.9 g and 141 seeds per fruit. The seeds are obovooid to subdiscoid, little to very compressed, albuminous, with a gelatinous endosperm surrounding the entire embryo of the axial type, continuous linear circined to imbricate. They have an average of 2.43 mm in length, 1.93 mm in width, 0.34 mm in thickness and a mass of 1.70 g. The forehead ornamentation is reticulated, forming a mesh with straight to sinuous walls and the presence of filiform projections. Germination was classified as phanerocotyledon, epigeal, curved, with foliate cotyledons beginning between the 7th and 10th days, the formation of eophylls was observed between 14th and 54th days and metaphiles between the 28th and 100th day after sowing. The seedling and young plant have a pivoting root system, with absorbent hair and branched lateral roots. The eofilos and metaphilos were differentiated by phyllotaxis, shape, margin, base, apex and indument. The morphometric aspects of the Solanum L species proved to be relevant for species recognition, in addition to distinguishing it from other invasive species.