Two species and their landscape
The current POWO treatment distinguishes Polaskia chichipe and P. chende. Both occur in Mexico and are associated with dry vegetation. Studies around Caltepec in Puebla describe populations on volcanic substrates. Material from these sites provides detailed knowledge of local population biology while retaining the separate distribution of each species. [2-WWW] [Otero-Arnaiz et al. 2003] [Ordoñez-Salanueva et al. 2017]
In Polaskia chichipe, branched stems form a crown and local people harvest the fruits. Desirable plants are retained when fields are prepared and are also introduced into gardens. This creates a mosaic of wild scrub, plants retained in agricultural landscapes and cultivated populations. Different management types can occur close together, allowing pollen to move among them. [Otero-Arnaiz et al. 2003] [Otero-Arnaiz et al. 2005]
Reproduction and early development
Flowers of Polaskia chichipe receive pollen from other plants, and some can also produce fruits after self-pollination. Experiments restricting pollinator access showed a predominant contribution from daytime visits in the seasons studied. Paternity analysis confirmed that fertilization by other plants predominated and that gene flow connected populations. These results concern this species and the population systems examined. [Otero-Arnaiz et al. 2003] [Otero-Arnaiz et al. 2005]
In Polaskia chende, light stimulates germination of fresh seeds. Some seeds remain in soil for more than five years, with dormancy changing through time. Seedlings beneath nurse shrubs emerged in greater numbers and survived longer than those in open ground. The seed bank and survival of young plants form two distinct stages of population regeneration. [Ordoñez-Salanueva et al. 2017]
Tissues and the root environment
An experiment on Polaskia chichipe seedlings showed that osmotic stress changes the development of the shoot and xylem vessels. Collapsed parenchyma cells adjoining cells that retained turgor were more frequent in stressed tissues. Responses depended on seedling age. The result describes development in mannitol-containing medium and distinguishes experimentally observed plasticity from cultivation recommendations for adult plants. [Rosas et al. 2012]
Rich communities of mycorrhizal fungi were recorded in milpa-chichipera, whose native vegetation patches are dominated by Polaskia chichipe. Community composition varied with season and land use. The comparison sampled soil across the plant mosaic, so it describes the landscape root environment rather than a fungal assemblage attributable exclusively to one cactus. [Jiménez-Martínez et al. 2026]