摘要
为了探讨水稻根负向光性形成与钙信号传导的关系,以水稻种子根为材料,用不同浓度的钙信号试剂[氯化钙、钙通道有机阻断剂异搏定、钙通道无机阻断剂氯化镧、钙调素抑制剂氯丙嗪(CPZ)以及生长素极性运输抑制剂NPA]处理水稻种子根,以1/10Hoagland培养液为对照,并用100～200μmol/(m2.s)单侧光照射24h。实验结果表明,适量的CaCl2使水稻种子根负向光性增强并使其生长加快,负向光性增强是由于外源Ca2+进一步促进生长素从向光侧向背光侧运输引起的,与生长速率加快无关;同时,随着钙通道有机阻断剂、无机阻断剂、钙调素抑制剂以及生长素极性运输抑制剂浓度的上升,水稻根的负向光性及生长均受显著抑制,当异搏定的浓度大于100μmol/L,LaCl3的浓度大于12.5μmol/L,负向光性消失,种子根的生长也受到严重的影响;而60μmol/L钙调素抑制剂氯丙嗪、6μmol/L生长素极性运输抑制剂NPA也使得根负向光性消失,根的生长几乎停止;向LaCl3溶液、异搏定溶液以及NPA溶液中添加100μmol/L CaCl2可使负向光性及生长速率得到不同程度的恢复,表明钙离子作为第二信使系统,与生长素相互作用,参与光信号调控水稻根生长和负向光性形成。
In order to investigate the relationship between calcium signaling and negative phototropism of rice roots, different concentration of calcium signaling reagent such as CaCl2, organic calcium channel blocker（verapamil）, inorganic calcium channel blocker（LaCl3）, calcineurin inhibitor chloropromaize（CPZ）, auxin polar transport inhibitor（NPA） were used to treat rice seminal roots which were unilaterally illuminated at an intensity of 100-200 μmol/（m2·s） for 24 h. Results showed that negative phototropism curvature and growth rate of rice roots were enhanced by a proper dose of CaCl2. Further experiments testified that it is because more IAA was transported from irradiated side to shaded side by exogenous Ca2＋ that negative phototropism curvature was enhanced rather than increased growth rate. Simultaneously, negative phototropism curvature and growth rate of rice roots were inhibited by inhibitors above, and the inhibiting effects were enhanced as the rising concentration of inhibitors. Roots would stop growing and negative phototropism characteristic would disappear when the concentration reached a certain degree, such as 100 μmol/L verapamil, 12.5 μmol/L LaCl3, 60 μmol/L CPZ and 6 μmol/L NPA. 100 μmol/L CaCl2 relieved the inhibition degree of LaCl3, verapamil and NPA. The results indicated that calcium ion plays an important role as a second messenger in the process of light signaling regulating rice roots growth and negative phototropism.
出处
《中国水稻科学》
CAS
CSCD
北大核心
2013年第3期265-272,共8页
Chinese Journal of Rice Science
基金
国家自然科学基金资助项目(31071353)
经济林木种质改良与资源综合利用湖北省重点实验室(黄冈师范学院)开放基金资助项目(2013000503)
关键词
水稻
根
负向光性
钙信号
生长素极性运输
钙离子通道阻断剂
rice root negative phototropism calcium signaling polar auxin transport calcium channel blockers
