木本植物休眠的诱导因子及其细胞内Ca^(2+)水平的调节作用  

INDUCING FACTOR AND REGULATINHG ROLE OF INTRACELLULAR Ca^(2+) LEVEL FOR WOODY PLANT BUD DORMANCY *

作　　者：简令成[1] 卢存福[2] 邓江明 李积宏 LIPaul H 

机构地区：[1]中国科学院植物研究所北京100093 [2]北京林业大学生物学院 [3]Laboratory of Plant Hardiness, Department of Horticutural Science, University of Minnesota, St. Paul, MN55108, USA [4]Department of Agricultural,Food and Nutritional Science, University of Alberta, Edmonton, Alberta, T6G 2P5, Canada

出　　处：《应用与环境生物学报》2004年第1期1-6,共6页Chinese Journal of Applied and Environmental Biology

基　　金：国家自然科学基金 (30 2 71 0 67)的资助~~

摘　　要：本研究揭示 ,越冬木本植物在夏秋转变过程中对光周期变化十分敏感 .在北纬 4 5°的明尼苏达州圣保罗地区 ,当日照变短 72min时 (2 0 0 0年 8月 8日 ) ,桑树顶芽细胞质浆和细胞核内即出现Ca2 + 流入 ,而在夏天长日照时期 (7月上、中旬 )很少有Ca2 + 存在的细胞质和细胞核 .12d后 (8月 2 0日 ) ,观测到桑树和杨树芽已经开始进入生理休眠 .从 9月上旬到 11月中旬 ,细胞质和细胞核内的Ca2 + 浓度显著升高 ,11月中旬达到高峰 .与此同时 ,芽的生理休眠深度也迅速增加 ,并于 11月达到高峰 ,4 2d培养也不见萌芽迹象 .到 12月中旬 (12月 2 0日 ) ,细胞核和细胞质中的Ca2 + 浓度又恢复到夏季观察到的低水平 ,显示早先进入细胞质和细胞核中的Ca2 + 已经被排出 .此后 ,在 12月下旬 (2 5日 ) ,检测到生理休眠的终结 .室外补充光照实验进一步证明 ,只有日照缩短才会引发植物进入自然生理休眠 ;保持日照长度不变 ,晚夏时期的自然温度降低 ,不能诱导植株停止生长和进入休眠 .这些结果表明 ,越冬木本植物在晚夏到冬季的生理休眠发展过程中 ,日照缩短引起的核和质内Ca2 + 的流入不仅起着传递日照变短信号的作用 ,导致生理休眠的起始 ;而且 ,高水平的核 /质Ca2 + 浓度还起着发展和保持深度生理休眠的作用 .图版 1图 1表The present study revealed that the overwintering woody plants were very sensitive to photoperiod change during summer-autumn transition. At 45°N 95°W in St. Paul, Minnesota,when day length was shortened by 1 h and 12 min in late summer(August 8), an influx of Ca 2+ has been triggered ,as indicated by Ca 2+ deposits appearing in the cytosol and nuclei in mulberry apical bud cells. The bud physiological dormancy of mulberry and poplar initiated 12 days after the Ca 2+ influx was observed(August 20). From early September to middle November, the number of Ca 2+deposits in the cytosol and nuclei greatly increased and reached maximum in middle November.At the same time, bud dormancy rapidly developed and reached the highest degree in November. By the middle of December (December 20), the Ca 2+concentration in the cytosol and nuclei restored to the low level as that observed in summer,showing that the previously entered Ca 2+ in the cytosol and nuclei had been removed out. Thereafter,physiological dormancy terminated in late December. The supplemental light experiments in the field further confirmed that the physiological dormancy in overwintering woody plants was initiated only by day length shortening,not by decline of natural temperature in late summer.These results suggested that a short- day length-induced Ca 2+ influx in the cytosol and nucleus not only act as the messenger of shortened photoperiod signal transduction,causing the initiating of dormancy, but also a high levels of Ca 2+ concentration in the cytosol and nuclei involve in the development and maintenance of the high degree of dormancy. Plate 1, Fig 1, Tab 2, Ref 23

关 键 词：木本植物 休眠 诱导因子 光周期 抗冻性 桑树 杨树 

分 类 号：Q945[生物学—植物学]