GERMINATION AND EARLY SEEDLING GROWTH OF TEHUACAN VALLEY CACTI SPECIES - THE ROLE OF SOILS AND SEED INGESTION BY DISPERSERS ON SEEDLING GROWTH

This study determined the effect of imbibition, temperature, and mecha nical and acid scarification on germination of eight cacti species, si mulating seed ingestion by birds and bats. The effect of shading and s oils on seedling growth of two columnar species was also analysed, con sidering environmental modifications produced by nurse plants. Only Pa chycereus hollianus increased its germination after seeds were soaked in acid solutions, whereas for the other species none of the treatment s increased their germination. Shading affected the growth of Neobuxba umia tetetzo seedlings, whereas soils beneath nurse plants increased s eedling growth of P. hollianus, indicating that soils help survival th rough early-critical stages. (C) 1998 Academic Press Limited.