Overexpression of MdATG8i improves water use efficiency in transgenic apple by modulating photosynthesis, osmotic balance, and autophagic activity under moderate water deficit

• DOI: 10.1038/s41438-021-00521-2
• Publication Date: 2021-04-01T00:02:45Z
• Authors: Xin Jia; Ke Mao; Ping Wang; Yu Wang; Xumei Jia; Liuqing Huo; Xun Sun; Runmin Che; Xiaoqing Gong; Fengwang Ma
• Keywords: Water Use Efficiency; Osmoregulation; Drought Tolerance; Photosynthetic efficiency; Plant Physiology; Photosynthetic capacity

Abstract Water deficit is one of the major limiting factors for apple ( Malus domestica ) production on Loess Plateau, a cultivation area in China. The identification genes related to regulation water use efficiency (WUE) crucial aspect crop breeding programs. As conserved degradation and recycling mechanism eukaryotes, autophagy has been reported participate various stress responses. However, relationship between WUE not explored. We have shown that protein apple, MdATG8i , plays role improving salt tolerance. Here, we explored its biological function response long-term moderate drought stress. results showed MdATG8i- overexpressing OE) plants exhibited higher than wild-type (WT) under conditions. Plant can be increased by photosynthetic efficiency. Osmoregulation critical plant resistance adaptation. Under conditions, capacity accumulation sugar amino acids were OE WT plants. could attributed their ability maintain optimal stomatal aperture, organized chloroplasts, strong antioxidant activity. overexpression also promoted autophagic activity, which was likely changes described above. In summary, our demonstrate lines conditions because they maintained robust photosynthesis, effective osmotic adjustment processes,