PDF(Pubmed)
Abstract：
Low-temperature stress (LTS) drastically affects vegetative and reproductive growth in fruit crops leading to a gross reduction in the yield and loss in product quality. Among the fruit crops, temperate fruits, during the period of evolution, have developed the mechanism of tolerance, i.e., adaptive capability to chilling and freezing when exposed to LTS. However, tropical and sub-tropical fruit crops are most vulnerable to LTS. As a result, fruit crops respond to LTS by inducing the expression of LTS related genes, which is for climatic acclimatization. The activation of the stress-responsive gene leads to changes in physiological and biochemical mechanisms such as photosynthesis, chlorophyll biosynthesis, respiration, membrane composition changes, alteration in protein synthesis, increased antioxidant activity, altered levels of metabolites, and signaling pathways that enhance their tolerance/resistance and alleviate the damage caused due to LTS and chilling injury. The gene induction mechanism has been investigated extensively in the model crop Arabidopsis and several winter kinds of cereal. The ICE1 (inducer of C-repeat binding factor expression 1) and the CBF (C-repeat binding factor) transcriptional cascade are involved in transcriptional control. The functions of various CBFs and aquaporin genes were well studied in crop plants and their role in multiple stresses including cold stresses is deciphered. In addition, tissue nutrients and plant growth regulators like ABA, ethylene, jasmonic acid etc., also play a significant role in alleviating the LTS and chilling injury in fruit crops. However, these physiological, biochemical and molecular understanding of LTS tolerance/resistance are restricted to few of the temperate and tropical fruit crops. Therefore, a better understanding of cold tolerance\'s underlying physio-biochemical and molecular components in fruit crops is required under open and simulated LTS. The understanding of LTS tolerance/resistance mechanism will lay the foundation for tailoring the novel fruit genotypes for successful crop production under erratic weather conditions.
摘要：
低温胁迫（LTS）会严重影响水果作物的营养和生殖生长，导致产量大幅下降和产品质量下降。在水果作物中，温带水果，在进化时期，发展了宽容的机制，即，暴露于LTS时对冷冻和冷冻的适应能力。然而,热带和亚热带水果作物最容易受到LTS的影响。因此,水果作物通过诱导LTS相关基因的表达来响应LTS，这是为了适应气候。应激反应基因的激活导致光合作用等生理生化机制的变化,叶绿素生物合成，呼吸,膜成分变化，蛋白质合成的改变，增加抗氧化活性，改变了代谢物的水平，以及增强其耐受性/抗性并减轻由于LTS和冷害造成的损害的信号通路。在模式作物拟南芥和几种冬季谷物中已经广泛研究了基因诱导机制。ICE1(C-重复结合因子表达1的诱导物)和CBF(C-重复结合因子)转录级联参与转录控制。在作物植物中充分研究了各种CBF和水通道蛋白基因的功能，并破译了它们在包括冷胁迫在内的多种胁迫中的作用。此外,组织养分和植物生长调节剂，如ABA，乙烯,茉莉酸等.,在缓解水果作物的LTS和冷害方面也起着重要作用。然而,这些生理，对LTS耐受性/抗性的生化和分子理解仅限于少数温带和热带水果作物。因此,在开放和模拟LTS条件下，需要更好地了解水果作物耐寒性的潜在生理生化和分子成分。对LTS耐受性/抗性机制的理解将为在不稳定的天气条件下为成功的作物生产定制新型水果基因型奠定基础。
