Application of Unconventional Supporting Systems for the Rooting of Critically Endangered Tree Species
Photo: Viswambharan Sarasan.
Young plants of the critically endangered endemic tree Trochetiopsis ebenus potted on from micropropagation
Tree species are difficult to propagate in culture compared to other plants. Rooting and transplantation stages are the final and crucial, and often very difficult, stages of micropropagation. Development of a strong root system and thereby better absorption of water and nutrients by the transplanted plant is of paramount importance. In Trochetiopsis ebenus and T. erythroxylon (Critically Endangered trees from St. Helena) plants developed in agar-based cultures were not suitable for transplantation due to a poorly developed root system. This led to poor growth of plants during the weaning stage. Uptake of water by the roots is limited due to damage incurred during transplantation and poor contact with the substrate. Improving the quality of root systems developed in culture was the major objective of this investigation.
This work examined the applications of two unconventional supporting materials, SorbarodsTM and FlorialiteTM, for rooting and transplantation and was published in 2003 (Sarasan, 2003). Improved rooting and survival of the transplanted propagules were achieved and the findings of this work have been useful in developing further modifications to protocols for some of the extremely difficult recalcitrant plants in culture in the Micropropagation Unit. Following the success of this work autotrophic micropropagation systems are being used in a pilot study.
Project Team
Project Leader: Sarasan, Viswambharan
HPE
Viswambharan Sarasan
Project Partners and Collaborators
St Helena
Agriculture and Forestry Department
St Helena National Trust