Zhang Yi-Nan, Zhuang Ye, Wang Xiao-Guo, Wang Xiao-Dong
Henan Province Dryland Agricultural Engineering Technology Research Center/College of Agronomy, Henan University of Science and Technology, Luoyang, Henan, China.
Technology Research Center, Henan Tobacco Company, Luoyang, Henan, China.
Front Plant Sci. 2024 Sep 26;15:1442618. doi: 10.3389/fpls.2024.1442618. eCollection 2024.
In recent years, more severe droughts have occurred frequently in many parts of the world, drought stress is the primary abiotic stress factor restricting the growth and quality of flue-cured tobacco. Therefore, screening dryland cultivation-compatible flue-cured tobacco varieties will help reduce the negative impact of drought.
Tobacco varieties were selected: Qinyan 96 (Q96), Zhongyan 101 (Z101), Yunyan 87 (Y87), and Yunyan 116 (Y116). A pot experiment was conducted with four water supply gradients: sufficient, mild stress, moderate stress, and severe stress. The aim was to analyze inter-varietal differences in agronomic traits, photosynthetic traits, reactive oxygen species (ROS) metabolism, and antioxidant enzyme system under drought stress. Additionally, the drought resistance of four flue-cured tobacco varieties was evaluated using principal component analysis and membership function analysis.
The results showed that drought intensification inhibited seedling growth and development across all varieties, with Q96 showing the least decrease and Y116 the greatest. With the increasing degree of drought stress, photosynthetic rates (P), transpiration rate (T), and stomatal conduction (G) have shown gradually decreasing trends, while substomatal cavity CO concentration (C) showed a growing trend. Severe drought corresponded with lower chlorophyll content and decreased the maximal photochemical efficiency (F/F), photosystem II (PSII), and photochemical quenching coefficient (qP) in all varieties, while steady-state non-photochemical quenching (NPQ) increased. Increased drought stress led to significantly higher reactive oxygen species (ROS) and malondialdehyde (MDA) content accumulation in tobacco seedlings. The antioxidant enzyme activities in, Q96, Z101, and Y87 increased under mild drought stress, whereas Y116 showed decreased activity.
The drought resistance ranking among the four varieties is as follows: Q96 > Z101 > Y87 > Y116. Therefore, Q96 is a promising drought-tolerant breeding material that can be used as a reference for dryland cultivation of flue-cured tobacco.
近年来，世界许多地区频繁发生更为严重的干旱，干旱胁迫是限制烤烟生长和品质的主要非生物胁迫因素。因此，筛选适合旱地种植的烤烟品种将有助于减少干旱的负面影响。
选取烟草品种：秦烟96（Q96）、中烟101（Z101）、云烟87（Y87）和云烟116（Y116）。进行盆栽试验，设置四个供水梯度：充足、轻度胁迫、中度胁迫和重度胁迫。目的是分析干旱胁迫下各品种在农艺性状、光合性状、活性氧（ROS）代谢和抗氧化酶系统方面的品种间差异。此外，利用主成分分析和隶属函数分析对四个烤烟品种的抗旱性进行评价。
结果表明，干旱加剧抑制了所有品种烟苗的生长发育，其中Q96下降最少，Y116下降最多。随着干旱胁迫程度的增加，光合速率（P）、蒸腾速率（T）和气孔导度（G）均呈逐渐下降趋势，而胞间CO₂浓度（C）呈上升趋势。重度干旱导致所有品种叶绿素含量降低，最大光化学效率（Fv/Fm）、光系统II（PSII）和光化学猝灭系数（qP）下降，而稳态非光化学猝灭（NPQ）增加。干旱胁迫加剧导致烟苗活性氧（ROS）和丙二醛（MDA）含量显著积累。轻度干旱胁迫下，Q96、Z101和Y87的抗氧化酶活性增加，而Y116的活性降低。
四个品种的抗旱性排序为：Q96＞Z101＞Y87＞Y116。因此，Q96是一种有潜力的耐旱育种材料，可为烤烟旱地栽培提供参考。
