Dormancy in seed of Phellodendron wilsonii is mediated in part by abscisic acid
1994
Lin, T.P. | Chen, M.H. | Lin, C.H.
A regime of temperatures alternating between 35 degrees C (8 h) and 10 degrees C (16 h) proved to be a specific method for breaking dormancy of seeds of Phellodendron wilsonii. The relationship between the germination capacity after about 13 days of incubation under this regime and the logarithm of the amount of ABA in the seed before incubation yielded a high correlation coefficient. The final germination capacity under this regime was poorly correlated with the amount of ABA in seeds before incubation. These observations suggest that at least part of the germination behavior is controlled by the amount of abscisic acid in the seed. Stratification decreased the amount of ABA but resulted in only 8-25% germination relative to other dry stored seeds failed to germinate under suboptimal conditions, namely, incubation at 22 degrees C with 12 h light. This phenomenon indicates that some unknown mechanism is the major factor that controls the dormant state, and the effect of this mechanism are overcome only by the specific alternating-temperature regime. Fluctuations in temperature failed, however, to reduce the ABA content of seeds during the incubation period. We conclude that some unknown factor contributes to the dormancy of seeds of P. wilsonii although the level of ABA definitely plays a minor role in the maintenance of seed dormancy.
显示更多 [+] 显示较少 [-]