Involvement of auxin in growth and stress response of cucumber
Rahat Sharif, Ли Су, Xuehao Chen, Xiaohua Qi
Abstract
Cucumber (<italic>Cucumis sativus</italic> L.), an important vegetable, popular worldwide for its crispy texture and special flavor. Plant hormones such as auxin stands out for its dominating function in morpho- and organogenic processes, formation of organs as well as regulation of tropic responses. These developmental processes are entirely or partially dependent on auxin biosynthesis, transport, and signal transduction. In cucumber, auxin not only fine-tunes its morphogenesis but also response to environmental stress. The role of auxin in regulating different organs (root, hypocotyl, shoot, leaf, tendril, flower, and fruit) development in cucumber was reviewed in the present paper. Moreover, the role of auxin in cucumber response to biotic stresses (powdery mildew, downy mildew, and nematode infections) and abiotic stresses (heat, iron, waterlogging, cold, salinity, drought, and heavy metal stresses) was discussed. Finally, we pointed out the blind spots and future research thoughts to extend our understanding of this myriad molecule in cucumber growth and stress biology.