Agriculture Reference
In-Depth Information
Air
Temp
Seed
Activation of
Metabolism
Growth
Imbibition
Water
Fig. 2
Seed germination.
the standard temperature of germination of rice seeds. 10ºC had
been cited as the minimum critical temperature below which
rice does not germinate (Yoshida 1981b). In japonica rice the
germination of rice seeds is optimum at 30ºC but germination
was satisfactory up to 20ºC. However, the germination rate
decreases gradually below 20ºC (Ueno and Miyoshi 2005)
(Table 1).
Rice is a low temperature sensitive crop especially during
seedling, tillering, panicle development and fl owering stages,
which can easily be injured by cold treatment. Most of the high
yielding varieties cannot be used in direct sowing because
Table 1
Temperature and seed germination.
30
⁰
C
Optimum
Very good germination
20
⁰
C Critical Medium Germination
10
⁰
C Limiting Germination Failure
