Storage of Acacia mangium and A. auriculiformis pollen.

Abstract

Storage conditions tested included liquid nitrogen and vacuum drying for long-term storage and air drying for short term storage. Pollen viability following storage was tested by in vitro staining methods using 5-bromo-4-chloro-3-indole-β-galactoside (X-gal) or fluorescein diacetate (FDA). Results were checked using in vivo pollen tube growth and pod set. FDA staining gave a better indication of pollen viability than X-gal. The use of freshly prepared FDA for each staining is recommended. Pollen stored in a deep freeze after vacuum drying produced pod set after 1 year's storage and gave FDA staining after 3 years. This method has 2 advantages: it uses equipment available in most laboratories, and vacuum dried pollen can be transported easily from one site to another. Pollen was stored successfully for 1 year in liquid nitrogen. Pollen subjected to a freeze-thaw-freeze-thaw cycle lost its viability after 9 days. Air-dried pollen could be stored successfully for up to 3 days but viability was reduced. Vacuum-dried and air-dried storage treatments differed between the 2 species. The potential of pollen storage as a method for conserving superior genetic material of Acacia is discussed.