Storage time effect on the germination of Haematoxylum campechianum in Campeche, Mexico

Haematoxylum campechianum L. (Fabaceae), is an economically and culturally important tropical tree distributed across Central America and the Yucatan Peninsula, Mexico. To contribute to the conservation of this species, it is important to understand the seed germination process; however, research in this subject on H. campechianum remains scarce. We evaluated the relationship between the H. campechianum seed storage time and its fresh weight and germination. Mature seeds were collected in the municipality of Palizada, Campeche, Mexico, from 2016 to 2019, stored at 25 degrees C and 60%-80% relative humidity until experimentation after the 2019 collection. Seed replicates (10, comprising 25 seeds) were weighed to estimate fresh weight per collection year. Seed viability was determined by means of the tetrazolium test, while germination was carried out in Petri dishes using cotton as a substrate under a 12-hr photoperiod at 25 degrees C. The seeds collected in 2019 presented a high viability and germination (100% and 98.5% respectively), in contrast with those collected in 2018, which presented a drastic reduction in the values for these parameters (55% and 54%, respectively). Null viability and germination were observed in seeds collected in 2016 and 2017. The seeds collected in 2016 showed the highest fresh weight values than the other years sampled. The results indicate that the viability and germination of H. campechianum seeds were observed to be affected by storage time, the recently harvested seeds presented a higher viability and germination than older seeds. Therefore, the H. campechianum seeds could be recalcitrant because they presented an accelerated ageing process over the collection periods.