Fatemeh Hosseini1, Mohammad Reza Mosaddeghi2, Anthony Roger Dexter3, Mozhgan Sepehri4. 1. Department of Soil Science, College of Agriculture, Isfahan University of Technology, Isfahan, 84156-83111, Iran. 2. Department of Soil Science, College of Agriculture, Isfahan University of Technology, Isfahan, 84156-83111, Iran. mosaddeghi@cc.iut.ac.ir. 3. Institute of Soil Science and Plant Cultivation (IUNG-PIB), ul. Czartoryskich 8, 24-100, Pulawy, Poland. 4. Department of Soil Science, School of Agriculture, Shiraz University, Shiraz, 7144165185, Iran.
Abstract
MAIN CONCLUSION: Under combined drought and mechanical stresses, mechanical stress primarily controlled physiological responses of maize. Piriformospora indica mitigated the adverse effects of stresses, and inoculated maize experienced less oxidative damage and had better adaptation to stressful conditions. The objective of this study was to investigate the effect of maize root colonization by an endophytic fungus P. indica on plant water status, physiological traits and root morphology under combined drought and mechanical stresses. Seedlings of inoculated and non-inoculated maize (Zea mays L., cv. single cross 704) were cultivated in growth chambers filled with moistened siliceous sand at a matric suction of 20 hPa. Drought stress was induced using PEG 6000 solution with osmotic potentials of 0, - 0.3 and - 0.5 MPa. Mechanical stress (i.e., penetration resistances of 1.05, 4.23 and 6.34 MPa) was exerted by placing weights on the surface of the sand medium. After 30 days, leaf water potential (LWP) and relative water content (RWC), root and shoot fresh weights, root volume (RV) and diameter (RD), leaf proline content, leaf area (LA) and catalase (CAT) and ascorbate peroxidase (APX) activities were measured. The results show that exposure to individual drought and mechanical stresses led to higher RD and proline content and lower plant biomass, RV and LA. Moreover, increasing drought and mechanical stress severity increased APX activity by about 1.9- and 3.1-fold compared with the control. When plants were exposed to combined stresses, mechanical stress played the dominant role in controlling plant responses. P. indica-inoculated plants are better adapted to individual and combined stresses. The inoculated plants had greater RV, LA, RWC, LWP and proline content under stressful conditions. In comparison with non-inoculated plants, inoculated plants showed lower CAT and APX activities which means that they experienced less oxidative stress induced by stressful conditions.
MAIN CONCLUSION: Under combined drought and mechanical stresses, mechanical stress primarily controlled physiological responses of maize. Piriformospora indica mitigated the adverse effects of stresses, and inoculated maize experienced less oxidative damage and had better adaptation to stressful conditions. The objective of this study was to investigate the effect of maize root colonization by an endophytic fungus P. indica on plant water status, physiological traits and root morphology under combined drought and mechanical stresses. Seedlings of inoculated and non-inoculated maize (Zea mays L., cv. single cross 704) were cultivated in growth chambers filled with moistened siliceous sand at a matric suction of 20 hPa. Drought stress was induced using PEG 6000 solution with osmotic potentials of 0, - 0.3 and - 0.5 MPa. Mechanical stress (i.e., penetration resistances of 1.05, 4.23 and 6.34 MPa) was exerted by placing weights on the surface of the sand medium. After 30 days, leaf water potential (LWP) and relative water content (RWC), root and shoot fresh weights, root volume (RV) and diameter (RD), leaf proline content, leaf area (LA) and catalase (CAT) and ascorbate peroxidase (APX) activities were measured. The results show that exposure to individual drought and mechanical stresses led to higher RD and proline content and lower plant biomass, RV and LA. Moreover, increasing drought and mechanical stress severity increased APX activity by about 1.9- and 3.1-fold compared with the control. When plants were exposed to combined stresses, mechanical stress played the dominant role in controlling plant responses. P. indica-inoculated plants are better adapted to individual and combined stresses. The inoculated plants had greater RV, LA, RWC, LWP and proline content under stressful conditions. In comparison with non-inoculated plants, inoculated plants showed lower CAT and APX activities which means that they experienced less oxidative stress induced by stressful conditions.
Authors: Frank Waller; Beate Achatz; Helmut Baltruschat; József Fodor; Katja Becker; Marina Fischer; Tobias Heier; Ralph Hückelhoven; Christina Neumann; Diter von Wettstein; Philipp Franken; Karl-Heinz Kogel Journal: Proc Natl Acad Sci U S A Date: 2005-09-08 Impact factor: 11.205
Authors: Helmut Baltruschat; József Fodor; Borbála D Harrach; Elżbieta Niemczyk; Balázs Barna; Gábor Gullner; Anna Janeczko; Karl-Heinz Kogel; Patrick Schäfer; Ildikó Schwarczinger; Alga Zuccaro; Andrzej Skoczowski Journal: New Phytol Date: 2008-08-04 Impact factor: 10.151
Authors: Salme Timmusk; Islam A Abd El-Daim; Lucian Copolovici; Triin Tanilas; Astrid Kännaste; Lawrence Behers; Eviatar Nevo; Gulaim Seisenbaeva; Elna Stenström; Ülo Niinemets Journal: PLoS One Date: 2014-05-08 Impact factor: 3.240