Effect of bioactive products on the germination of cryopreserved teak pollen grains

Abstract

Teak (Tectona grandis L. f.), is a native tree from Southeast Asia considered of great economic value, mainly for its wood. As part of the efforts for the genetic improvement of this specie, protocols for pollen cryopreservation have been developed; however, it is essential to ensure its viability and efficient germination for future crosses of selected material. The objective of the present work was to evaluate the effect of spirostanic analogue of brassinosteroids (Biobras-16^®) and a mixture of oligogalacturonides (Pectimorf^®) on the in vitro germination, size of pollen and pollen tube length of cryopreserved teak pollen. The experiments consisted of evaluating the germination of pollen with 0, 4 and 8 months of cryopreservation in culture medium without supplements, supplemented with 0.001 and 0.050 Biobras-16^® mg L^-1 and, Pectimorf^® 5 and 10 mg L^-1. Germination data were analyzed using a General Linear Model, while pollen tube length and pollen area using analysis of variance (ANOVA) and correlation analysis. It was demonstrated that both bioactive products promote in vitro germination of cryopreserved pollen grains for 4 and 8 months, where Biobras-16^® at 0.001 mg L^-1 showed results that are more consistent. Pectimorf^® stimulated the elongation of the pollen tube, which could favor the fecundation processes.