Abstract
In the seasonally dry tropical regions around the globe, water availability is the most limiting factor for plant growth and affects cambial activity. However, identification of the other climatic factors that regulate cambial activity is necessary to understand the growth of tropical semiarid species. Here we studied two congeneric species, Cordia oncocalyx and C. bicolor, to investigate the cambial activity response to environmental factors. These species occur in the Brazilian semiarid region, in areas that contrast in humidity. Cambial activity was quantified in both species by counting the number of cambial cell layers and the relationships between cambial activity and abiotic factors were investigated using a generalized linear mixed model (GLMM). Despite the modest variation in photoperiod in seasonally dry tropical regions, cambial activity significantly increased in response to longer days. We found that cambial activation depended on the milder average temperature of the wet season, and the cambial cell division rate was driven by pulse water availability. Also, the increase of temperature is a limiting factor for the cambial activity, which may represent limitation of plant growth due to climate change.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
