Effect of environmental heterogeneity on field germination of Opuntia tomentosa (Cactaceae, Opuntioideae) seeds

We studied in Opuntia tomentosa the effect of plant shade (orientation and distance), and the place where the seeds remained before germination. Seeds were collected in 1998 and a) sown immediately on soil (non-buried seeds), b) stored in the laboratory and sown on soil during the 1999 rainy season...

Descripción completa

Detalles Bibliográficos
Autores: Olvera-Carrillo, Y, Mendez, I, Marquez-Guzman, J, Barradas, VL, Huante, P, Orozco-Segovia, A, Sánchez-Coronado, ME
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:México
Institución:Universidad Nacional Autónoma de México
Repositorio:Sistema de Información de la Facultad de Ciencias, UNAM
OAI Identifier:oai:repositorio.fciencias.unam.mx:11154/2208
Acceso en línea:http://hdl.handle.net/11154/2208
Access Level:acceso abierto
Palabra clave:Ecology
Environmental Sciences
Lava field
Physiological dormancy
Plant shade effect
Safe sites
Seed burial
Descripción
Sumario:We studied in Opuntia tomentosa the effect of plant shade (orientation and distance), and the place where the seeds remained before germination. Seeds were collected in 1998 and a) sown immediately on soil (non-buried seeds), b) stored in the laboratory and sown on soil during the 1999 rainy season (control) or c) buried after collection (under the shade of a tree, a rock and in an open space), exhumed 7 months later and sown in 1999 (exhumed seeds). Seeds were sown under or outside the shade of several trees: or on the northern, eastern and western sides of a 14-m-tall tree. In 1999, germination was high in all samples, but the control seeds had delayed germination. After two rainy seasons, non-buried seeds had the lowest germination rate. Germination was not affected by the distance from the tree. Outside of the plant's shade, germination was low. Germination was affected more by the environmental heterogeneity than by the individual plant shade. Germination probabilities were the highest at 16-19 degrees C