MORFOANATOMIA E GERMINAÇÃO DA SEMENTE DE BATATA-DE-PURGA (Operculina hamiltonii (G. DON) D. F. Austin & Staples), CONVOLVULACEAE

Abstract

The objective of this work was to characterize the morphological, anatomical and germinative aspects of purge-potato seeds, in order to understand the development of the structures and their germinative behavior. The morphological aspects were studied through biometrics in 100 seeds with the aid of a digital caliper, and the germination type and morphology were observed daily through the monitoring of the germination of the seeds in vermiculite substrate. The anatomy of the seed was analyzed through free hand cuts with stylet, and the blades were later stained for microscopic analysis and photographed. For the characterization of germination, 200 seeds were used, 100 of which were non-scarified (control) and 100 were submitted to scarification in sandpaper of nº 100 for 30 seconds. Both were put to germinate, in four replicates of 25 seeds, put in rolls of germitest paper in B.O.D. at 25 ° C in the 21-day period. The seeds are compressed laterally globose-angular, smooth, coloring ranging from gray to green, hard forehead and depressed thread. Anatomically it presents a palisade layer, evidencing a lucid line, and presence of cracks with mucilage after germination, some layers of sclerenchyma in the outermost layer and parenchyma in the innermost. Germination of the epigeic and phanerocotyledonous type, germination potential of 0% in non-scarified seeds and 75% in scarified seeds, characterizing tegument impermeability through physical dormancy was verified. The seed of O. hamiltonii presents the morphological pattern of Convolvulaceae seeds and has a hard integument, being evidenced by the presence of the lucid line in the palisade tissue of the forehead of the integument, preventing the absorption of the water for the germinative process.