Epigeal germinators

Table 4.5. Some examples of hypogeal and epigeal germinators...

Fig. 4.11. Seedling development I. Two species in which the cotyledons are the storage organs but one showing hypogeal germination and the other epigeal germination...

Fig. 4.13A and B. Seedling development III. Two epigeal germinators with foliate cotyledons. Note that the testa is automatically removed from the cotyledons in Cucumis but that the seed coat (pericarp) in Helianthus remains, enclosing the cotyledons until the latter are well developed... 

Fig. 6.26A-F. Changes in the cotyledons and axes of Vigm sesquipedalis during seedling development. C cotyledons H hypocotyl E epicotyl R radicle P plumule. Scale on the right-hand ordinate is for C, and on the left-hand ordinate for H, E, R and P. Germination is epigeal. Based on Oota et al., 1953 [108]...

Fig. 6.27. Changes in protein (o), lipid (x), total chlorophyll a and b ( ), a-cellulose (hatched bar) and hemicellulose/starch (unhatched bar) content per cotyledon during germination and seedling development in Lupinus albus. R time of radicle elongation H time of hypocotyl expansion L time of expansion of first leaves and plumule. Germination is epigeal. Based on Parker, 1975 [115]...

Jack pine seed does not require stratification (Yeatman, 1984). It has epigeal (aboveground) germination. Favourable seedbeds include mineral soil, decomposed organic layers less than a few centimetres thick, and burned or scarified duff (Rudolf, 1965 Cayford and McRae, 1983 Greene... 

Western larch seeds germinate epigeally about the time of snowmelt, Ifom late April to early June, usually 1 to 2 weeks before associated tree species (Shearer, 1967). Germination is usually rapid and complete after natural stratification during winter. Air temperatures of about 27°C are optimal for germination, but seeds can stiU germinate at temperatures that are 10° to 15°C cooler (Schopmeyer, 1974). 

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