This paper describes changes in the structure of buds and vascular cambium as well as in protein content of one-year-old dormant branches of Eucommia ulmoides Oliv. in water-culture conditions. Results confirm the exi...This paper describes changes in the structure of buds and vascular cambium as well as in protein content of one-year-old dormant branches of Eucommia ulmoides Oliv. in water-culture conditions. Results confirm the existence of 2 quiescences (Q1, Q2) and 1 rest (R) phases in this tree during the dormancy period. In the R time, the E. ulmoides cambium was unable to reactivate even though the tree was subjected to exogenous IAA, suitable temperature or required luminosity. Furthermore, pistillate trees entered the dormant phase earlier than staminate ones. The protein content in the bark during Q1 increased significantly ( P < 0.01), but drastically decreased in the R period, before rising up again at the onset of Q2 ( P < 0.01). Even though the change pattern of protein content was similar, its occurrence is much earlier in staminate than in pistillate plants. SDS-PAGE revealed a 'special' protein band of 11.8 kD in the transitional Q1-R-Q2 stages. This 'special' protein bands would be related to the cambial dormancy and to the regulation of the Q1-R-Q2 transition.展开更多
文摘This paper describes changes in the structure of buds and vascular cambium as well as in protein content of one-year-old dormant branches of Eucommia ulmoides Oliv. in water-culture conditions. Results confirm the existence of 2 quiescences (Q1, Q2) and 1 rest (R) phases in this tree during the dormancy period. In the R time, the E. ulmoides cambium was unable to reactivate even though the tree was subjected to exogenous IAA, suitable temperature or required luminosity. Furthermore, pistillate trees entered the dormant phase earlier than staminate ones. The protein content in the bark during Q1 increased significantly ( P < 0.01), but drastically decreased in the R period, before rising up again at the onset of Q2 ( P < 0.01). Even though the change pattern of protein content was similar, its occurrence is much earlier in staminate than in pistillate plants. SDS-PAGE revealed a 'special' protein band of 11.8 kD in the transitional Q1-R-Q2 stages. This 'special' protein bands would be related to the cambial dormancy and to the regulation of the Q1-R-Q2 transition.
