Abstract:
In some European countries,
Adonis flammea
is very rare and endangered primarily
due to increasing fertilizer and herbicide use, more efficient seed cleaning, and s
trong soil
acidification.
The aims of this study were to determine the requirements for embryo
growth, dormancy break, and seed germination to characterize the type of seed dormancy
(
via
effects of GA
3
) and to evaluate the effects of light on germination a
bility.
Germination
responses of
A. flammea
were tested in light and dark conditions at three alternating
temperatures (
15/
5°C, 20/10°C, 25/15°C) after
stratification. Embryo growth was
determined by measuring its lengths. Fresh seeds did not germinate dur
ing one month of
incubation in either light or darkness over a range of temperatures.
Seeds of
A. flammea
had underdeveloped embryos that must grow from about 0.2 to 1.5 mm in length before
radicle emergence (germination); thus they had Morphological Dorma
ncy (MD). In
addition to MD, the seeds also had Physiological Dormancy (PD) at maturity in mid
-
July;
moreover, the
embryos grew during warm stratification, and the seeds needed a
subsequent period of cold stratification to germinate. Thus, MD had been brok
en, but PD
prevented germination. Therefore, the seeds have morpho
-
physiological dormancy.
Germination was promoted by 12 weeks of warm stratification followed by 12 weeks of
cold stratification.
In conclusion, good conservation
management in arable land f
or
A.
flammea
involves annual cultivation, ideally in mid
-
summer (warm stratification) without
subsequent disturbance until the following summer.
Keywords:
E
mbryo length, Gibberellic acid, Morpho
-
physiological seed dormancy.
