Seed germination and seedling characteristic of ipomoea and Merremia (Convolvulaceae) in Lambayeque (Peru)

Background and Objective: Studies were undertaken to determine the effects of in vivo germination of mechanically scarified with and without sandpaper, chemically scarified with H₂SO₄ for 40 min and without H₂SO₄ and in vitro germinated with sandpaper and with sandpaper and GA₃ seeds of Ipomoea and Merremia in the Lambayeque region and surrounding areas (Peru). Materials and Methods: Seeds of 16 species of Ipomoea and 3 species of Merremia collected from Lambayeque (Peru) were germinated under in vivo and in vitro conditions and measured the angle of divergence of seedlings and the data were analysed by ANOVA. Results: In the in vivo germination process, mechanical and chemical scarification caused an increase in germination and in the in vitro germination process mechanical scarification with sandpaper and GA₃ also caused an increase in germination. Seedling emergence was observed and recorded and found not to fit the classical models of hypogeal and epigeal emergence and in the seedling morphology the degree of apical cleft of paracotyledonary leaves and the angle of divergence between the two lobes of a paracotyledon were determined. The length of the apical cleft was highly correlated (r = 0.81) with the angle of divergence. Conclusion: Convolvulaceae is the most advanced family that produces seeds with physical dormancy (water-impermeable seed coat).