Base temperatures required for germination of
tion of cultivars based on anticipated seed zone
Festuca species were 3.2C for rapid germinators,
temperatures will provide rapid germination and
3.6 to 6C for medium germinators, and 4 to 6C
may lead to improved establishment on poorly
for poor germinators. Heat units (HU) (growing
managed sandy soils in cold climates.
degree-days >10C) calculated for the rapid ger-
minator were 129C-d, 120 to 140C-d for medium
LITERATURE CITED
germinators, and 135 to 191C-d for the poor
germinators. Radford and Henzell (1990) report-
Angus, J.F., R.B. Cunningham, M.W. Moncur, and
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D.H. Mackenzie (1981) Phasic development in
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perature. Furthermore, they speculated that any
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AOSA (1970) Rules for testing seeds. In Proceed-
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ings of the Association of Official Seed Analysts, 60: 1
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116.
sequently fail to germinate.
Bierhuizen, J.F., and W .A. Wagenvoort (1974)
The mean germination of Festuca cultivars was
Some aspects of seed germination in vegetables. 1.
significantly (p < 0.05) regressed with mean Atg
The determination and application of heat sums
(Fig. 2) and heat units (Fig. 3). Germination
and minimum temperature for germination.
decreased as Atg and HU increased. The Atg and
Scientific Horticulture, 2: 213219.
HU regressions explained 91% and 66% of the
Brar, G.S., and A.J. Palazzo (1995a) Tall and hard
variation in germination, respectively.
fescue responses to periodic soil water deficits.
Cultivars that germinated rapidly had lower
Journal of Agronomy and Crop Science, 175: 221229.
HU and Atg values, so they have the chance to
Brar, G.S., and A.J. Palazzo (1995b) Shoot and root
establish in the field earlier than medium and
development of tall and hard fescues in two dif-
slow germinators (Brar and Stewart 1994).
ferent soils. Journal of Environmental Quality, 24:
Rapid and total germination are the most
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obvious factors distinguishing the cultivars used
Brar, G.S., and B.A. Stewart (1994) Germination
in this study. The two TFs (Clemfine and Tribute)
under controlled temperature and field emerg-
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ence of 13 sorghum cultivars. Crop Science, 34:
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Hegarty, T.W . (1973) Temperature coefficient
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(Q10), seed germination and other biological pro-
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Heydecker, W . (1966) Clarity in recording ger-
preted with caution, but they suggest that selec-
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