摘要
Drought stress typically causes heavy losses in apple production and uncovering the mechanisms by which apple tolerates drought stress is important in apple breeding.MdSIZl is a SUMO(small ubiquitin-like modifier)E3 ligase that promotes SUMO binding to substrate proteins.Here,we demonstrate that MdSIZl in apple has a negative relationship with drought tolerance.MdSIZ1 RNAi transgenic apple trees had a higher survival rate after drought stress.During drought stress they had higher leaf water potential,reduced ion leakage,lower H_(2)O_(2)and malondialdehyde contents,and higher catalase activity.In addition,MdSIZl RNAi transgenic plants had a higher net photosynthetic rate during the latter period of drought stress.Finally,the transgenic apple trees also altered expression levels of some microRNAs in response to drought stress.Taken together,these results indicate that apple MdSIZl negatively regulates drought stress by enhancing leaf water-holding capacity and antioxidant enzyme activity.
基金
the National Natural Science Foundation of China(31872080)
the Start-up Funds of Northwest A&F university to Xuewei Li(2452020216).
