Tabassum Tahira, Farooq Muhammad, Ahmad Riaz, Zohaib Ali, Wahid Abdul, Shahid Muhammad
1Department of Agronomy, University of Agriculture, Faisalabad, 38040 Pakistan.
2The UWA Institute of Agriculture, The University of Western Australia, Perth, WA 6001 Australia.
Physiol Mol Biol Plants. 2018 Sep;24(5):845-856. doi: 10.1007/s12298-018-0547-y. Epub 2018 Jul 4.
Plants retain the preceding abiotic stress memory that may aid in attainment of tolerance to subsequent stresses. This study was conducted to evaluate the influence of terminal drought memory (drought priming) and seed priming in improving drought tolerance in wheat ( L.). During first growing season, wheat was planted in field under optimal (well-watered) and drought stress imposed at reproductive stage (BBCH growth stage 49) until maturity (BBCH growth stage 83). Seeds collected from both sources were subjected to hydropriming or osmopriming (with 1.5% CaCl solution); while, dry seed was taken as control. Treated and control seeds, from both sources, were sown in soil filled pots. After the completion of seedling emergence, pots were maintained at 50% water holding capacity (drought) or 100% water holding capacity (well-watered). Drought stress suppressed the plant growth (2-44%), perturbed water relations (1-18%) and reduced yield (192%); however, osmolytes accumulation (3-14%) and malondialdehyde contents (26-29%) were increased under drought. The crop raised from the seeds collected from terminal drought stressed plants had better growth (5-63%), improved osmolyte accumulation (13-45%), and lower lipid peroxidation (3%) than the progeny of well-watered crop. Seed priming significantly improved the crop performance under drought stress as compared to control. However, osmopriming was more effective than hydropriming in this regard as it improved leaf area (9-43%), tissue water status (2-47%), osmolytes accumulation (6-48%) and grain yield (14-79%). In conclusion, terminal drought induced modifications in seed composition and seed priming improved generational drought tolerance through improvement in tissue water status and osmolytes accumulation, and decrease in lipid peroxidation.
植物保留先前的非生物胁迫记忆，这可能有助于获得对后续胁迫的耐受性。本研究旨在评估终末期干旱记忆（干旱引发）和种子引发对提高小麦（L.）耐旱性的影响。在第一个生长季节，将小麦种植在田间，在生殖阶段（BBCH生长阶段49）施加最佳（充分浇水）和干旱胁迫，直至成熟（BBCH生长阶段83）。从这两种来源收集的种子进行水引发或渗透引发（用1.5%氯化钙溶液）；而干种子作为对照。来自这两种来源的处理种子和对照种子播种在装满土壤的花盆中。幼苗出土完成后，将花盆保持在50%持水量（干旱）或100%持水量（充分浇水）。干旱胁迫抑制了植物生长（2 - 44%），扰乱了水分关系（1 - 18%）并降低了产量（19 - 2%）；然而，在干旱条件下，渗透调节物质积累（3 - 14%）和丙二醛含量（26 - 29%）增加。与充分浇水作物的后代相比，从终末期干旱胁迫植物收集的种子培育出的作物生长更好（5 - 63%），渗透调节物质积累改善（13 - 45%），脂质过氧化更低（3%）。与对照相比，种子引发显著改善了干旱胁迫下的作物表现。然而，在这方面渗透引发比水引发更有效，因为它改善了叶面积（9 - 43%）、组织水分状况（2 - 47%）、渗透调节物质积累（6 - 48%）和籽粒产量（14 - 79%）。总之，终末期干旱诱导种子成分发生变化，种子引发通过改善组织水分状况和渗透调节物质积累以及降低脂质过氧化，提高了代际耐旱性。
