Starchy Pollen in Commelinoid Monocots

Abstract

The Commelinoid monocots are a monophyletic group comprising the Arecales, Commelinales, Poales and Zingiberales, plus the unplaced family Dasypogonaceae. Pollen from 149 taxa was examined qualitatively for starch as the primary storage product. Starchy pollen was found in 134 taxa (90 % of the sample) of Commelinoid monocots. Starchy pollen thus appears be a characteristic feature of the Commelinoid monocots. Starchy pollen can be easily observed with minimal preparation, making it a demonstrable character useful in the classroom or teaching laboratory. Furthermore, starchy pollen grains were found to be signi®cantly larger in diameter than non-starchy grains, con®rming previous hypotheses regarding pollen size and starch.

Pollen starch reserves in tomato relatives: Ecophysiological implications

“…Regarding pollen size, it has been observed in species of other families that starchy pollen grains were larger (Baker & Baker, 1979;Grayum, 1985;Zona, 2001;Ló pez et al, 2006). It may be noted that the two related species of the tomato group, which had exclusively starchy pollen, also had larger pollen grains.…”

“…However, as the number of species studied has increased, several exceptions have emerged (e.g. Zona, 2001). This includes some evidence that suggests that pollen starch content does not grealy influence the pollination mode and vice versa (Roulston & Buchmann, 2000).…”

Pollen performance, cell number, and physiological state in the early-divergent angiosperm Annona cherimola Mill. (Annonaceae) are related to environmental conditions during the final stages of pollen development

“…For instance, Pelargonium pollen shows less starch at 25 and 30 ºC than at 15 ºC (Sears 1926), and the same species shows starchy pollen when grown in higher latitudes compared to starchless pollen in lower latitudes (for review see Baker and Baker 1979). Some palm species show seasonal variations with starchless pollen in winter and starchy pollen in summer (Zona 2001). Studies in Sorghum also show the effect of temperature on starch hydrolysis, with the production of starchless pollen and considerably reduced pollen germination at high temperatures (Jain et al 2007).…”

Assessing diet and seasonality in the Lower Pecos canyonlands: an evaluation of coprolite specimens as records of individual dietary decisions

“…However, a recent study suggests that natural starch rain may be a more common environmental contaminant than has been previously realized in archaeological starch research (Laurence 2010). While this remains unresolved, it is clear that starch frequently enters the atmosphere through pollen grain rupture associated with precipitation and other weather patterns (Currie et al 2000;D'amato et al 2007;Erpenbeck et al 2005;Garcia 2010;Kuang et al 2005;Pacini 2006;Wang et al 2004;Zona 2001).…”