Metwally Rabab A, Soliman Shereen A
Botany and Microbiology Department, Faculty of Science, Zagazig University, Zagazig, 44519, Egypt.
Bot Stud. 2023 Feb 9;64(1):4. doi: 10.1186/s40529-023-00368-x.
Trichoderma viride are well known for their biocontrol capabilities, but little is known about how they stimulate plant development and increase their resistance to salt stress. One of the main abiotic factors limiting crop development and yield is salt stress. Therefore, the purpose of this work was to ascertain how NaCl effects on T. viride growth as well as on the seedlings morphological and physio-biochemical parameters of tomato (Solanum lycopersicum L.) under plate culture conditions. Additionally, a pot experiment was conducted to determine how T. viride affected the development characteristics of tomato plants subjected to various salt concentrations (50 and 100 mM NaCl). T. viride's contribution to tomato seedling stress tolerance was also closely examined.
Results showed that 100 mM NaCl decreased the colony diameter of T. viride by 13.4% compared to the control. Under plate and greenhouse conditions, tomato seedlings exposed to salt exposure exhibited an overall decline in growth. Also, a reduction in relative water content (RWC) and protein contents occurred under salt stress. At the same time, increases were found in proline, total phenolics, flavonoids, HO content, malondialdehyde, likewise the activities of peroxidase (POD), catalase (CAT), polyphenol oxidase (PPO), and ascorbate peroxidase (APX) enzymes. Even though, with T. viride application, the salt negative effects on both morphological and physio-biochemical parameters were mitigated to a greater extent. T. viride increased proline and total antioxidant capacity (TAC) in tomato seedlings at 100 mM NaCl by an average of 20.66 and 43.82% compared to their comparable control. T. viride increased the activities of CAT, PPO, and APX enzymes by 74.6, 58.48, and 61.61% at 50 mM NaCl compared to non-saline control seedlings. As well, T. viride decreased MDA and HO contents by an average of 14 and 24.8% in tomato seedlings at 50 mM NaCl compared to their comparable control. Also, under 100 mM NaCl, the T. viride-treated tomato seedlings showed increased total phenolics (17.85%) and flavonoids (33.17%) compared to non- treated one.
Hence, our research sheds new insight on the pathways by which T. viride can boost tomato seedling tolerance to salt stress at morphological and physio-biochemical levels by activating both enzymatic and non-enzymatic antioxidant defense systems.
绿色木霉以其生物防治能力而闻名，但对于它们如何刺激植物生长发育并增强其对盐胁迫的抗性却知之甚少。盐胁迫是限制作物生长发育和产量的主要非生物因素之一。因此，本研究旨在确定在平板培养条件下，氯化钠对绿色木霉生长以及番茄（Solanum lycopersicum L.）幼苗形态和生理生化参数的影响。此外，还进行了盆栽试验，以确定绿色木霉对处于不同盐浓度（50和100 mM氯化钠）下番茄植株发育特性的影响。同时，也密切研究了绿色木霉对番茄幼苗耐胁迫能力的贡献。
结果表明，与对照相比，100 mM氯化钠使绿色木霉的菌落直径减小了13.4%。在平板和温室条件下，遭受盐胁迫的番茄幼苗生长总体下降。此外，盐胁迫下相对含水量（RWC）和蛋白质含量降低。同时，脯氨酸、总酚、类黄酮、过氧化氢（HO）含量、丙二醛含量增加，过氧化物酶（POD）、过氧化氢酶（CAT）、多酚氧化酶（PPO）和抗坏血酸过氧化物酶（APX）的活性也增加。尽管如此，施用绿色木霉后，盐对形态和生理生化参数的负面影响在很大程度上得到缓解。与相应对照相比，在100 mM氯化钠条件下，绿色木霉使番茄幼苗中的脯氨酸和总抗氧化能力（TAC）平均增加了20.66%和43.82%。与非盐胁迫对照幼苗相比，在50 mM氯化钠条件下，绿色木霉使CAT、PPO和APX的活性分别增加了74.6%、58.48%和61.61%。同样，在50 mM氯化钠条件下，与相应对照相比，绿色木霉使番茄幼苗中的丙二醛和过氧化氢含量平均降低了14%和24.8%。此外，在100 mM氯化钠条件下，与未处理的番茄幼苗相比，经绿色木霉处理的番茄幼苗总酚（17.85%）和类黄酮（33.17%）含量增加。
因此，我们的研究揭示了绿色木霉通过激活酶促和非酶促抗氧化防御系统，在形态和生理生化水平上提高番茄幼苗耐盐胁迫能力的新途径。
