Vivipary and light quality effects on seed germination of the columnar cactus, Cereus jamacaru

Abstract

Vivipary is a remarkable trait in the Cactaceae family. Here, we reported a case of vivipary in Cereus jamacaru and observed which season had the highest vivipary incidence by examining the types of fruits and seeds produced during two contrasting periods in a seasonally dry tropical forest in northeastern Brazil. Additionally, because seeds of this species are positively photoblastic, a germination experiment was conducted to confirm whether seeds inside viviparous fruits (VFs) exhibited changes in light sensitivity. Seeds from VFs were then subjected to different light quality treatments, and their germination was compared with that observed in seeds from non‐viviparous fruits (NVFs). Vivipary only occurred in fruits produced at the end of the rainy season. Viviparous fruits’ seeds had a higher germination percentage under far‐red light than NVFs’ seeds, suggesting that vivipary may favor seed germination under canopy‐shade light and therefore provide new avenues for survival in semiarid environments.