Recruiting mechanisms of Cylindropuntia leptocaulis (Cactaceae) in the Southern Chihuahuan Desert |
| |
| Institution: | 2. Laboratorio de Oncogenomica, Instituto Nacional de Cancerologia, Tlalpan, Mexico;3. Unidad de Investigaciones Biomedicas en Cancer, Instituto Nacional de Cancerologia, Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de México (UNAM), Tlalpan, Mexico;4. Unidad de Bioquimica, Instituto Nacional de Nutrición (INCMNSZ), Tlalpan, Mexico;5. Direccion de Infecciones Cronicas y Cancer, Instituto Nacional de Salud Publica, Cuernavaca, México;11. Servicio de Tumores de Mama, Subdirección de Cirugia, Instituto Nacional de Cancerologia, Tlalpan, Mexico |
| |
| Abstract: | Sexual reproduction and vegetative propagation require the establishment of morphologically diverse reproductive structures (seedlings and stem segments). This study assesses both types of Cylindropuntia leptocaulis recruitment in two microenvironments protected from herbivory (in open space and under the canopy of Larrea tridentata) and with two soil types (collected below L. tridentata canopy and from open space).An observational study revealed that sexual establishment was very limited (only 8 juveniles/ha were found), while clonal establishment was more frequent (59 juveniles/ha); both types of propagule were found only under shrub canopy.Field experiments showed that, as in other Cylindropuntia species but contrasting with findings for Opuntia species, seeds germinated and seedlings survived under nurse plants as well as in open space, but they grew faster in the former environment. Faster growth under canopy shade provides better chances of successful recruitment to later life-cycle stages. Stem segments never established in open space, requiring the shade of nurse plants. This may be due to physiological constraints imposed by their small volume. In synthesis, the results indicate that clonal propagation is the most important recruitment mechanism in C. leptocaulis populations, and that it takes places under shrub canopy. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
