Nursery pre-treatment positively affects reintroduced plant performance via plant pre-conditioning, but not via maternal effects

Pre-release treatments have long been neglected in plant translocation science, despite being crucial for reintroduction success. Practitioners sometimes adopt acclimation and pre-treatment to reduce environmentally mediated shocks at the recipient site, although the effects of these techniques are unclear. The conditions experienced during cultivation may affect the performance of plants once released. The influence of the cultivation environment, and the maternal effects from fertilizer and salt treatments, on post-release performance were investigated on Kosteletzkya pentacarpos, a threatened plant species growing in coastal wetlands. Two experimental translocation sites, representing the opposite ends of the ecological range of K. pentacarpos, were chosen: one was a nutrient-rich, freshwater site and the other was a nutrient-poor, brackish water site. Treatment with salt had negligible effects on performance, whereas fertilization positively affected the vegetative and reproductive performance of maternal plants throughout the growing season. Pre-treatment effects were most evident at the highest nutrient site, however, suggesting that pre-treatment could be connected to ‘memory’ in plants. No maternal effects were observed. Overall, results show that pre-treatment can increase the chances of survival and improve the performance of translocated plants at the recipient site. From an applied conservation perspective, ex situ cultivation and nursing conditions may play a key role in establishing self-sustaining populations during plant translocation. These results have important implications for the use of K. pentacarpos for the restoration of saline wetlands, especially outside of its native range, but also for the conservation of the species via conservation translocation in general.