Jr. Rowley et Jj. Skvarla, CORRODED EXINES FROM HAVINGAS LEAF MOLD EXPERIMENT - STRUCTURE OF FAGUS AND QUERCUS EXINES, Review of palaeobotany and palynology, 83(1-3), 1994, pp. 65-72
Structure of exine units of Fagus sylvatica L. and Quercus robur L. be
came evident after six years in leaf mold. These exines appeared simil
ar to those early in development and to exines on mature pollen follow
ing laboratory experiments involving Gunnar Erdtman's acetolysis plus
plasma ashing or oxidation with potassium permanganate. In Fagus the r
od-shaped exine units showed a difference in diameter from a minimum o
f 0.1 mu m at distal ends to 0.3 mu m or more basally. A core and an o
uter binder zone were evident in these units. Material in the core zon
e differed from the binder zone in having a weaker secondary electron
signal. In Quercus, rods of exine unit structure were exposed. They we
re, like ''experimentally'' oxidized pollen, about 0.1 mu m in diamete
r. In severely corroded pollen of Fagus the ectexine appeared to be en
tirely eroded except for the resistant exine units. Exine units appear
ed to originate from the endexine.