Histochemical and ultrastructural analysis of tapetum and sporoderm development in relation to precocious pollenkitt production of Garcinia dulcis (Roxb.) Kurz

Author(s)
Pornsawan Sutthinon, Upatham Meesawat, Silvia Ulrich, Jürg Schönenberger
Abstract

Garcinia dulcis (Roxb.) Kurz (Clusiaceae) is a medicinal plant native to Southeastern Asia, with a peculiar, precocious pollenkitt production in early microspore development. We aimed to find out whether different secretory activities of the tapetum or a premature sporoderm development provides additional evidence for our recent hypothesis for the precocious pollenkitt production. Histology, histochemistry and ultrastructure of tapetum and sporoderm development during pollenkitt secretion in Garcinia dulcis were conducted, based on light and electron microscopy analysis. The results showed that Garcinia dulcis possesses normal pollen development. The presence of two different pollen coating types, precocious pollenkitt (L1) and common pollenkitt (L2), in the anther tapetum indicate that they are produced in two different active stages of the secretory tapetum. The precocious pollenkitt production and transport to the locule takes place in early active tapetal cells at early tetrad to early microspore stage and is ongoing until late microspore stage. The production of the second type of pollenkitt (L2) starts shortly after the first active tapetum stage together with the formation of sporopollenin precursors. The sporoderm formation was completed at late microspore stage, when the tapetal cell walls start to disintegrate. Orbicules are lining the inner tapetum wall at middle to late microspore stage. ER (during early microspore stage) and plastids (during late microspore stage) were the two main sources of pollenkitt, which finally fused to pollenkitt droplets when the tapetal cells degenerated at mature bicellular pollen stage.

Organisation(s)
Department of Botany and Biodiversity Research
External organisation(s)
Kasetsart University, Prince of Songkla University, Österreichische Akademie der Wissenschaften (ÖAW)
Journal
Protoplasma
Volume
261
Pages
1281-1295
No. of pages
15
ISSN
1615-6102
DOI
https://doi.org/10.1007/s00709-024-01969-4
Publication date
11-2024
Peer reviewed
Yes
Austrian Fields of Science 2012
106049 Ultrastructure research, 106008 Botany
Keywords
ASJC Scopus subject areas
Plant Science, Cell Biology
Portal url
https://ucrisportal.univie.ac.at/en/publications/7ab3590b-4780-4d78-ab68-2a20d7a07dbc