Pollen-pistil size correlation and pollen size-number trade-off in species of Argentinian Nyctaginaceae with different pollen reserves

Large pollen at high temperature: an adaptation to increased competition on the stigma?

“…Increased temperature affects not only the size of produced pollen, as shown by our results, but is also likely to be an important determinant of the production rate in plants. Perhaps the lack of a relationship between size and the quantity of produced pollen reported by some authors (e.g., Aguilar et al 2002;Lopez et al 2005) can result from ignoring the effect of temperature on both pollen size and the resource pool available for male function.…”

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.…”

Transitions from distyly to homostyly are associated with floral evolution in the buckwheat genus (Fagopyrum)

“…This match between pollen size and style length within heterostylous species has long been recognized, and it has been considered to be an adaptation enabling compatible pollen to grow through the stylar tissue (Ganders, 1979; Dulberger, 1992; Barrett et al, 2000; Ferrero et al, 2009). Such within‐species selection, with a long style favoring large pollen, has been documented in comparative studies in numerous genera and families, suggesting that selection of pollen size is similar among species (Baker and Baker, 1982; Plitmann and Levin, 1983; Williams and Rouse, 1990; Bigazzi and Selvi, 2000; Roulston et al, 2000; Torres, 2000; Sarkissian and Harder, 2001; Aguilar et al, 2002; Yang and Guo, 2004; López et al, 2005; Jürgens et al, 2012; but see Cruden, 2009; Bedinger et al, 2011; Wang et al, 2016). Darwin (1877), however, showed that in seven distylous genera, pollen grain size was similar in the two morphs, while the pistil (style) of the L‐morph was about two or three times as long as that of the S‐morph, for example in Coccocypselum , Limnanthemum , and Linum .…”