Influence of buffelgrass pasture conversion on the regeneration, and reproduction of the columnar cactus, Pachycereus pecten-aboriginum in northwestern Mexico

Rates of buffelgrass (Pennisetum ciliare) conversion have been increasing in recent times in northwestern Mexico. However, nothing is known about the effect of conversion on native plant species. In this poster, we document the effect of buffelgrass conversion on the reproduction, and regeneration of the columnar cactus Pachycereus pecten-aboriginum.
We selected three buffelgrass pastures of different age (1-10 years), and adjacent thornscrub where P. pecten-aboriginum is abundant in three ranches from the state of Sonora. We estimated abundance, size distribution in paired plots, and during the flowering season, we estimated several reproductive parameters. We also set an experiment to explore if seedling establishment occurs in both areas.
Our results show that buffelgrass pasture conversion does not affect the abundance of P. pecten-aboriginum. However, significant differences were detected in population structure. No significant differences were detected for most reproductive parameters when comparing plants from the thornscrub, and the pasture. However, the experiment showed that no seedling were able to establish under pastures. Thus, our results show that buffelgrass pasture conversion does not affect the reproduction of P. pecten-aboriginum but has a significant effect on the regeneration of this columnar cactus.