Department of Postharvest Science of Fresh Produce, The Volcani Center, ARO, Bet-Dagan, Israel.
Plant Signal Behav. 2012 Sep 1;7(9):1158-62. doi: 10.4161/psb.21324. Epub 2012 Aug 17.
The potato tuber constitutes a model system for the study of dormancy release and sprouting, suggested to be regulated by endogenous plant hormones and their balance inside the tuber. During dormancy, potato tubers cannot be induced to sprout without some form of stress or exogenous hormone treatment. When dormancy is released, sprouting of the apical bud may be inhibited by sprout control agents or cold temperature. Dominance of the growing apical bud over other lateral buds decreases during storage and is one of the earliest morphophysiological indicators of the tuber's physiological age. Three main types of loss of apical dominance (AD) affect sprouting shape. Hallmarks of programmed cell death (PCD) have been identified in the tuber apical bud meristem (TAB-meristem) during normal growth, and are more extensive when AD is lost following extended cold storage or chemical stress. Nevertheless, the role of hormonal regulation in TAB-meristem PCD remains unclear.
块茎构成了研究休眠解除和萌芽的模式系统,据推测由内源植物激素及其在块茎内的平衡来调控。在休眠期间,块茎如果没有某种形式的胁迫或外源激素处理,就不能被诱导发芽。当休眠解除时,顶端芽的萌发可能会被萌芽抑制剂或低温抑制。在贮藏过程中,生长中的顶端芽对其他侧芽的优势会降低,这是块茎生理年龄的最早形态生理学指标之一。三种主要的顶端优势丧失(AD)类型会影响萌芽形态。程序性细胞死亡(PCD)的特征已在正常生长的块茎顶端分生组织(TAB-分生组织)中被识别,而在经过长时间冷藏或化学胁迫导致 AD 丧失后,PCD 更为广泛。然而,激素调节在 TAB-分生组织 PCD 中的作用仍不清楚。