Effect of in situ storage, light, and moisture on the germination of two wetland tropical trees

Seed germination was evaluated for Annona glabra L. and Pachira aquatica Aubl. in the wetland conditions of La Mancha, Veracruz, Mexico. These species have recalcitrant seeds and hydrochoral dispersal. Germination experiments were carried out under varying moisture (high, middle, and low) and light (below canopy and open sky) levels as well as after being stored in contrasting natural conditions. Seeds were stored both floating in water and buried in wetland soil for 15, 30, 60, and 90 days. P. aquatica seeds germinated faster in low and medium moisture, regardless of light intensity. After 45 days, for example, they exhibited 87-73% germination in medium-moisture/canopy and low-moisture/canopy treatments, respectively. In high moisture, seeds reached similar percentages after 60 days (80%). Storage by burial caused the death of seeds regardless the time they spent underground, while those stored in water germinated at a rate of over 90%. A. glabra seeds germinated better (98%) in low-moisture/sunny conditions. As to storage, they responded favorably to both burial and water techniques but germinated more readily in treatments that involved a long storage period. Evaluation of the germination behavior of A. glabra and P. aquatica seeds subject to varying in situ storage and germination conditions illustrates the response capacity of each species during early phases of development.