A PRELIMINARY STUDY ON NITRATE REDUCTASE ACTIVITY IN VIVO ATTENUATION OF FOUR SPECIES OF POPLAR SEEDLINGS
- Received Date: 1988-10-25
- Available Online: 2012-12-04
Abstract: Nitrate reductase (NR) activity and its in vivo attenuating rate of four species of poplar seedlings with different growth rate were studied. Generally high NR activity was found in the fast growing seedling. Higher NR activity in leaves were obtained, when seedlings were treated with KNO3 solution (20m mol/1). But the NR activity in leaves of fast growing seedling e. g. Populus deltcides Bartr. cv. "Lux" (ex, 1-69/55) and Fopulus euramericana (Dode) Guinier cv. I-214 were higher than in those of slow growing seedling e, g. Populus×popularis Hsü and Populus simonii Carr. The NR activity in detached leaves declined with time.The NR activity attenuation rate in detached leaves of poplar seedlings with different growth rate were different. Such as NR attenuation rate of Populus deltoides Bartr. cv. "Lux" (ex, I-69/55) was lower than that of Populus simonii Carr., they were 31% and 65% after four hours respectively. But the NR attenuation rate of Populus×popularis Hsü. was low after two hours and then it became higher. The use of NR attenuation rate in different species of poplar seedlings with different growing rates are discussed.