title: Enhancement of salinity tolerance during rice seed germination by presoaking with hemoglobin.
abstract: Salinity stress is an important environmental constraint limiting the productivity of many crops worldwide. In this report, experiments were conducted to investigate the effects of seed presoaking by bovine hemoglobin, an inducer of heme oxygenase-1 (HO-1), on salinity tolerance in rice (Oryza sativa) plants. The results showed that different concentrations of the hemoglobin (0.01, 0.05, 0.2, 1.0, and 5.0 g/L) differentially alleviated the inhibition of rice seed germination and thereafter seedling shoot growth caused by 100 mM NaCl stress, and the responses of 1.0 g/L hemoglobin was the most obvious. Further analyses showed that application of hemoglobin not only increased the HO-1 gene expression, but also differentially induced catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) activities or transcripts, thus decreasing the lipid peroxidation in germinating rice seeds subjected to salt stress. Compared with non-hemoglobin treatment, hemoglobin presoaking also increased the potassium (K) to sodium (Na) ratio both in the root and shoot parts after salinity stress. The effect is specific for HO-1 since the potent HO-1 inhibitor zinc protoporphyrin IX (ZnPPIX) blocked the positive actions of hemoglobin on seed germination and seedling shoot growth. Overall, these results suggested that hemoglobin performs an advantageous role in enhancement of salinity tolerance during rice seed germination.
authors: Laboratory Centre of Life Sciences, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China; E-Mails: 2008216034@njau.edu.cn (S.X.); njhubing@sina.com (B.H.); njheziyi@sina.com (Z.H.); 2010116135@njau.edu.cn (F.M.); 1328207@njau.edu.cn (J.F.).
authors: Sheng
authors: S
authors: Xu
authors: Bing
authors: B
authors: Hu
authors: Ziyi
authors: Z
authors: He
authors: Fei
authors: F
authors: Ma
authors: Jianfei
authors: J
authors: Feng
authors: Wenbiao
authors: W
authors: Shen
authors: Jie
authors: J
authors: Yang
mesh_terms: D000818:Animals; D060387:Ascorbate Peroxidases / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002417:Cattle; D018525:Germination / Q000187:drug effects*; D051547:Heme Oxygenase-1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D006454:Hemoglobins / Q000737:chemistry / Q000494:pharmacology*; D015227:Lipid Peroxidation / Q000187:drug effects; D012275:Oryza / Q000254:growth & development*; D018517:Plant Roots / Q000254:growth & development; D018520:Plant Shoots / Q000254:growth & development; D011188:Potassium / Q000494:pharmacology; D011524:Protoporphyrins / Q000494:pharmacology; D012639:Seeds / Q000254:growth & development; D012965:Sodium Chloride / Q000494:pharmacology; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D006454:Hemoglobins; D011524:Protoporphyrins; C017803:zinc protoporphyrin; D012965:Sodium Chloride; D060387:Ascorbate Peroxidases; D002374:Catalase; D051547:Heme Oxygenase-1; D013482:Superoxide Dismutase; D011188:Potassium