College of Life Sciences, Northwest A&F University, Yangling, 712100, Shaanxi, China.
National Center for Soybean Improvement, Key Laboratory of Biology and Genetics and Breeding for Soybean, Ministry of Agriculture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, 210095, China.
Environ Sci Pollut Res Int. 2021 Sep;28(33):45276-45295. doi: 10.1007/s11356-021-13755-3. Epub 2021 Apr 16.
Drought is a major environmental threat limiting worldwide crop production. Drought stress affects the tobacco quality and yield; therefore, the current research studies were undertaken to investigate the effectiveness of arbuscular mycorrhizal fungi (AMF) under drought stress on morphological and biochemical attributes of tobacco (Nicotiana tabacum L. variety Yunyan 87). AMF-inoculated and AMF-non-inoculated plants were maintained in a greenhouse and irrigated with a half-strength Hoagland solution (100 mL pot) once a week. At harvesting, the plant height, number of leaves, fresh and dry weights, mycorrhizal colonization, and concentration of leaf photosynthetic pigments and photosynthetic rate were measured. Data were statistically analyzed by ANOVA and the principal component (PCA) analyses. The effect of root colonization significantly increased biomass production and essential oil accumulation. Results showed that drought at mild and severe stressed levels significantly affected tobacco growth by decreasing plant height, biomass, and a number of leaves. However, inoculation of AMF considerably increased plant height, fresh and dry weights, chlorophyll (a, b), total chlorophyll, and carotenoid content by 43.84, 40.87 and 49.76, 185.29, 325.60, 173.12, and 211.49%, respectively. Compared with non-inoculated plants, AMF inoculation significantly enhanced the essential oil yield and the uptake of nitrogen, phosphorus, and potassium with the increase of 257.36, 102.71, and 90.76, 62.32, and 84.51%, respectively, in mild drought + AMF-treated plants. Similarly, the antioxidant enzymatic activity, glomalin-related soil protein (GRSP), and accumulation of phenols and flavonoids and osmolytes content were also significantly improved in inoculated plants under drought stress. Additionally, AMF inoculation significantly upregulated the lipoxygenase (LOX) and phenylalanine ammonia-lyase (PAL) enzymes by 197 and 298.44% under drought conditions. These findings depicted that the symbiotic association of AMF improved the overall growth pattern and secondary metabolism in tobacco plants under severe drought stress conditions and may be used as an approaching source of important drugs in the field of pharmacology.
干旱是限制全球作物生产的主要环境威胁。干旱胁迫会影响烟草的质量和产量；因此，进行了当前的研究，以研究丛枝菌根真菌（AMF）在干旱胁迫下对烟草（Nicotiana tabacum L.品种云烟 87）形态和生化特性的有效性。AMF 接种和非 AMF 接种的植物在温室中养护，并每周用半强度 Hoagland 溶液（每盆 100 毫升）浇水一次。收获时，测量株高、叶片数、鲜重和干重、菌根定植率以及叶片光合色素和光合速率的浓度。数据通过方差分析和主成分（PCA）分析进行统计分析。根定植的影响显著增加了生物量的产生和精油的积累。结果表明，在轻度和重度胁迫水平下的干旱显著影响了烟草的生长，降低了株高、生物量和叶片数。然而，AMF 的接种显著增加了株高、鲜重和干重、叶绿素（a、b）、总叶绿素和类胡萝卜素含量，分别增加了 43.84%、40.87%和 49.76%、185.29%、325.60%、173.12%和 211.49%。与未接种植物相比，AMF 接种显著提高了精油产量和氮、磷、钾的吸收，在轻度干旱+AMF 处理植物中，精油产量、氮、磷、钾的吸收分别增加了 257.36%、102.71%、90.76%、62.32%和 84.51%。同样，在干旱胁迫下，接种植物的抗氧化酶活性、球囊霉素相关土壤蛋白（GRSP）以及酚类、类黄酮和渗透物含量也显著提高。此外，在干旱条件下，AMF 接种显著上调了脂氧合酶（LOX）和苯丙氨酸解氨酶（PAL）酶的活性，分别增加了 197%和 298.44%。这些发现表明，在严重干旱胁迫条件下，AMF 的共生关系改善了烟草植物的整体生长模式和次生代谢，并且可以作为药理学领域重要药物的来源。
