Tabassum Tahira, Farooq Muhammad, Ahmad Riaz, Zohaib Ali, Wahid Abdul
Department of Agronomy, University of Agriculture, Faisalabad 38040, Pakistan.
Department of Agronomy, University of Agriculture, Faisalabad 38040, Pakistan; The UWA Institute of Agriculture, The University of Western Australia, LB 5005 Perth, WA 6001, Australia; College of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia.
Plant Physiol Biochem. 2017 Sep;118:362-369. doi: 10.1016/j.plaphy.2017.07.007. Epub 2017 Jul 8.
This study was conducted to evaluate the potential of seed priming following terminal drought on tolerance against salt stress in bread wheat. Drought was imposed in field sown wheat at reproductive stage (BBCH growth stage 49) and was maintained till physiological maturity (BBCH growth stage 83). Seeds of bread wheat, collected from crop raised under terminal drought and/or well-watered conditions, were subjected to hydropriming and osmopriming (with 1.5% CaCl) and were sown in soil-filled pots. After stand establishment, salt stress treatments viz. 10 mM NaCl (control) and 100 mM NaCl were imposed. Seed from terminal drought stressed source had less fat (5%), and more fibers (11%), proteins (22%) and total soluble phenolics (514%) than well-watered seed source. Salt stress reduced the plant growth, perturbed water relations and decreased yield. However, an increase in osmolytes accumulation (4-18%), malondialdehyde (MDA) (27-35%) and tissue Na contents (149-332%) was observed under salt stress. The seeds collected from drought stressed crop had better tolerance against salt stress as indicated by better yield (28%), improved water relations (3-18%), osmolytes accumulation (21-33%), and less MDA (8%) and Na contents (35%) than progeny of well-watered crop. Seed priming, osmopriming in particular, further improved the tolerance against salt stress through improvement in leaf area, water relations, leaf proline, glycine betaine and grain yield while lowering MDA and Na contents. In conclusion, changed seed composition during terminal drought and seed priming improved the salt tolerance in wheat by modulating the water relations, osmolytes accumulation and lipid peroxidation.
本研究旨在评估在终末期干旱后进行种子引发对面包小麦耐盐性的影响。在田间播种的小麦生殖阶段(BBCH生长阶段49)施加干旱,并持续至生理成熟(BBCH生长阶段83)。从终末期干旱和/或充分灌溉条件下种植的作物中收集面包小麦种子,进行水引发和渗透引发(用1.5%氯化钙),然后播种到装有土壤的花盆中。在植株定植后,施加盐胁迫处理,即10 mM氯化钠(对照)和100 mM氯化钠。与充分灌溉的种子来源相比,来自终末期干旱胁迫来源的种子脂肪含量较低(5%),纤维、蛋白质和总可溶性酚含量较高(分别为11%、22%和514%)。盐胁迫降低了植株生长,扰乱了水分关系并降低了产量。然而,在盐胁迫下观察到渗透调节物质积累增加(4 - 18%)、丙二醛(MDA)增加(27 - 35%)和组织钠含量增加(149 - 332%)。与充分灌溉作物的后代相比,从干旱胁迫作物收集的种子对盐胁迫具有更好的耐受性,表现为产量更高(28%)、水分关系改善(3 - 18%)、渗透调节物质积累增加(21 - 33%),MDA和钠含量更低(分别为8%和35%)。种子引发,尤其是渗透引发,通过改善叶面积、水分关系、叶片脯氨酸、甘氨酸甜菜碱和籽粒产量,同时降低MDA和钠含量,进一步提高了对盐胁迫的耐受性。总之,终末期干旱期间种子成分的变化以及种子引发通过调节水分关系、渗透调节物质积累和脂质过氧化作用提高了小麦的耐盐性。