Physiological Conditioning of Alibertia edulis (Rich) Seeds

Physiological conditioning of seeds has been shown to increase the uniformity of seedlings; thus, it has been useful for propagating native tree species from the Brazilian Cerrado which, otherwise, are difficult to propagate successfully. The objective of this work was to evaluate the effect of physiological conditioning of Alibertia edulis seeds by soaking for 5 or 10 days in solutions of varying osmotic potential. After conditioning, seeds were dried down to original water content, sown on sheets of germitest paper inside gerbox plastic boxes, and incubated at 25°C. We evaluated the effect of conditioning by studying seed germination and vigor. Seed conditioning by osmotic pretreatment showed positive effects; however, germination and growth of seedlings from seeds conditioned at osmotic potentials of -0.3 to -0.7 MPa were reduced. Osmoconditioning for 10 days at -0.7 MPa resulted in increased percent germination, indicating that the longest imbibition period in the osmotic solution of the lowest osmotic potential (-1.3 MPa) favored the seed germination process. A. edulis seeds did not require conditioning to attain high germination rates; nonetheless, osmotic conditioning reduced average seed-germination time.