Antioxidant Protection Mechanisms Reveal Significant Response in Drought-Induced Oxidative Stress in Some Traditional Rice of Assam,India     

Shamsun Nahar  Lakshminarayana R. Vemireddy  Lingaraj Sahoo  Bhaben Tanti 《水稻科学》2018,25(4):185-196

Drought tolerance levels and antioxidant protection mechanisms were evaluated for 21 traditional rice varieties of Assam, India, along with Sahbhagi Dhan (drought tolerant) and IR64 (drought sensitive) as controls. Drought was imposed in hydroponic culture with polyethylene glycol 6000 (PEG6000) that was initially standardized with different concentrations. All the rice varieties showed apparent decreases in growth characteristics under drought stress (initially at 15% for 7 d followed by 20% PEG6000 for 7 d in Yoshida medium). On the basis of standard evaluation score (SES), eight rice varieties showed high drought tolerance which were carried forward for further biochemical analyses. Based on different morpho- physiological parameters, SN03 (Bora), SN04 (Prosad Bhog), SN05 (Kola Joha), SN06 (Helash Bora), SN08 (Salihoi Bao), SN12 (Kola Amona), SN20 (Ronga Bora) and SN21 (Sok-Bonglong) were identified as promising drought tolerant varieties. The non-enzymatic antioxidants activities viz., glutathione, ascorbate and enzymatic antioxidant activities such as superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (GPX), ascorbate peroxidase (APX), glutathione reductase (GR) in shoots and roots of all the selected varieties revealed significant level of protection mechanisms as compared with controls. Enhancement in activities of the overall antioxidant enzymes including SOD, GPX, CAT, GR and APX under drought stress reflects their role in the adaptation process under water stress.  相似文献   

Marker-assisted introgression of QTLs for yield under moisture stress into elite varieties of rice (Oryza sativa)     

Jeevula N. Bhukya  Swarajyalakshmi N. Bollineni  Gopalakrishna Kadambari  Reddiyamini Bommisetty  Eswar R. Gudikati  Withanawasam M. Darsha  Keerthi Issa  Srividhya Akkareddy  Suresh N. Eslavath  Ajay K. Dokuparthi  Aparna Eragam  Vinodkumar N. Moode  Rameshbabu Pottepalem  Srilakshmi Chintala  Eswarareddy P. Narrareddy  Bahbhen Tanti  Mandal P. Nimai  Pallavi Muniraju  Yeswanth V. Janaki  Lakshminarayana R. Vemireddy 《Plant Breeding》2020,139(6):1076-1089

Rice production is severely constrained by the moisture stress. The present study was undertaken to transfer two important QTLs viz., (qDTY2.2 and qDTY4.1), which controls yield under moisture stress (DTY) into two elite varieties, that is, MTU1010 and NLR34449 through marker-assisted breeding. Foreground and background selections of backcross generations, that is, BC₁F₁, BC₂F₁ and BC₂F₂ identified several promising introgression lines (ILs) with two QTLs and single QTLs with an appreciable level of recovery of recipient parent genome. In ILs, the recovery of MTU1010 genome content was estimated to be 83%–93% while the recovery of NLR34449 was 84%–92%. The two-QTL ILs of MTU1010 and NLR34449 backgrounds (qDTY2.2 and qDTY4.1) have shown substantial yield advantage (32 to 84%) over the single-QTL ILs (either qDTY2.2 or qDTY4.1) under moisture stress conditions. Among all, two ILs, MBC-124 and NBC-127 are the best high yielding lines under moisture stress conditions. These outyielded ILs have the potential to be released as varieties in rainfed ecosystem and also can be used as donors in the existing breeding programme in rice.  相似文献   

Arsenic Stress Responses and Tolerance in Rice: Physiological,Cellular and Molecular Approaches     

Jyotirmay Kalita  Amit Kumar Pradhan  Zina Moni Shandilya  Bhaben Tanti 《水稻科学》2018,25(5):235-249

Arsenic (As), a potentially toxic metalloid released in the soil environment as a result of natural as well as anthropogenic processes, is subsequently taken up by crop plants. In rice grains, As has been reported in Asia, North America and Europe, suggesting a future threat to food security and crop production. As³⁺ by dint of its availability, mobility and phytotoxicity, is the most harmful species of As for the rice crop. Specific transporters mediate the transport of different species of As from roots to the aboveground parts of the plant body. Accumulation of As leads to toxic reactions in plants, affecting its growth and productivity. Increase in As uptake leads to oxidative stress and production of antioxidants to counteract this stress. Cultivars tolerant to As stress are efficient in antioxidant metabolism compared to sensitive ones. Iron and selenium are found to have ameliorating effect on the oxidative stress caused by As. Microbes, even many indigenous ones, in the plant rhizosphere are also capable of utilizing As in their metabolism, both independently and in association. Some of these microbes impart tolerance to As-stress in plants grown in As contaminated sites.  相似文献