Nurse plants, soil nutrients, and avian seed dispersal of wild chile peppers in a semiarid valley of Southern Mexico

Abstract

Despite its economic and culinary importance, our understanding of biological aspects in natural populations of Capsicum annuum var. glabriusculum (=Cag) is scarce. This study examines the association of Cag with two plants species, Celtis pallida (a shrub) and Neltuma laevigata (a tree) by considering nursing relationships, soil properties and avian seed dispersal, in a semiarid valley of Oaxaca, Mexico. Cag mature plants and seedlings were measured in two sampling sites (hedgerows and original vegetation), including their associated plants (nurse). Additionally, soil properties were registered and potential disperser birds if detected were recorded. Our results reveal a positive correlation between the presence of Cag and nurse species, coupled with low phosphorus and high nitrogen levels in soil. Cag's distribution is influenced by avian dispersers, highlighting the importance of Toxostoma curvirostre and Mimus polyglottos. Local hedgerows emerge as fundamentals for the conservation of Cag, serving as nurturing environments that promote micro-environmental conditions. Hence, to promote the permanence and expansion of Cag populations, we propose the preservation of species-specific nurse plants and the implementation of traditional agroforestry systems.