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[Objectives] The study aimed to explore the remedial effect of foliar spraying astaxanthin(ASTA)on submerged rice at tillering stage after de-submergence.[Methods] The rice variety ‘Ningjing 7’ as experimental material was planted in pot,and five treatments were set up at tillering stage:normal moisture management(indicated by CT);submergence stress+spraying water(CK);submergence stress+spraying 0.4 mmol·L-1 ASTA(ASTA-0.4);submergence stress+spraying 0.8 mmol·L-1 ASTA(ASTA-0.8);submergence stress+spraying 1.6 mmol·L-1 ASTA(ASTA-1.6). The leaves of rice were sampled at 0,1,2,3,5,7 days after spraying ASTA,and analyzed on the effect on the photosynthetic pigment content,the activities of antioxidant enzymes(SOD,CAT,POD,APX,GR),membrane lipid peroxidation(MDA)content,hydrogen peroxide(H2O2)content and soluble protein content. The leaves of rice were sampled at 0,3,6,9 days after spraying ASTA,and analyzed on the effect on the dry weight,plant height and total soluble sugar content. The yield and its components were measured by collecting representational three-pot rice at maturity.[Results] The results showed that after five days of submergence the number of tillers and green leaves per plant decreased significantly compared with CT,dry matter accumulation and chlorophyll content decreased,and oxidative damage was serious. Ultimately,it had an impact on yield. After de-submergence,foliar spraying ASTA could increase the activity of antioxidant enzymes,increase the contents of total soluble sugar and soluble protein,reduce the contents of H2O2 and MDA,alleviate oxidative damage,promote tillering,accelerate dry matter accumulation and reduce yield loss. In particularly,at 12 days after spraying,the number of tillers per plant,green leaves,and the contents of dry matter,chlorophyll a,total soluble sugar and soluble protein of ASTA-0.8 treatment increased significantly,and the activities of antioxidant enzymes increased,and the contents of H2O2 and MDA in leaves decreased. At 7 days after spraying,MDA content was 20.7% lower than CK,and H2O2 content was 9.4% lower than CK. The final yield of ASTA-0.8 treatment was the closest to CT,and the yield returned to 98.7% of CT.[Conclusions] When rice was submerged at tillering stage,foliar spraying 0.8 mmol·L-1 astaxanthin could remedy it. [ABSTRACT FROM AUTHOR]