■干旱是影响东北春玉米(ZeamaysL.)幼苗生长发育的关键限制因素。已发现5-硝基愈创木酚钠(5-NGS)可增强植物细胞代谢并促进幼苗生长,这可能会增加耐旱性。
■在本研究中,我们研究了在聚乙二醇(PEG-6000)诱导的渗透胁迫下,玉米幼苗对5-NGS溶液叶面施用的响应。建立了四个处理组:叶面施用蒸馏水(CK),5-NGS(NS)的叶面施用,渗透胁迫+叶面施用蒸馏水(D),和渗透胁迫+5-NGS(DN)的叶面施用。评估了四种处理下的植物特性,包括生长,光合和抗氧化能力。
■结果表明,在渗透胁迫下,玉米幼苗的生长受到抑制,光合能力和抗氧化能力均减弱。此外,脯氨酸和可溶性糖含量显着增加,幼苗相对含水量(RWC)降低。然而,应用5-NGS减轻了渗透胁迫对玉米幼苗生长参数的影响,特别是地下的生物量,干质量变化小于5%,相对含水量(RWC)增加。此外,用5-NGS处理通过增加叶绿素含量来恢复净光合速率(Pn),从而减轻了渗透胁迫对光合作用的抑制。光合电子传输,和细胞间CO2浓度(Ci)。此外,地上部分抗氧化酶的活性恢复,导致丙二醛(MDA)和H2O2减少约25%。值得注意的是,地下部分的酶活性表现出更显著的变化,MDA和H2O2含量降低50%以上。最后,5-NGS刺激可溶性糖作为渗透胁迫下的渗透保护剂和能量来源的代谢的双重作用,脯氨酸含量增加了30%以上。我们发现5-NGS在玉米幼苗中光合产物的积累和资源的有效分配中起作用。
■基于这些结果,我们确定,叶面施用5-NGS可以提高玉米幼苗的渗透胁迫耐受性。该研究为干旱条件下提高玉米产量提供了有价值的参考。
UNASSIGNED: Drought is a critical limiting factor affecting the growth and development of spring maize (Zea mays L.) seedlings in northeastern China. Sodium 5-nitroguaiacol (5-NGS) has been found to enhance plant cell metabolism and promote seedling growth, which may increase drought tolerance.
UNASSIGNED: In the present study, we investigated the response of maize seedlings to foliar application of a 5-NGS solution under osmotic stress induced by polyethylene glycol (PEG-6000). Four treatment groups were established: foliar application of distilled water (CK), foliar application of 5-NGS (NS), osmotic stress + foliar application of distilled water (D), and osmotic stress + foliar application of 5-NGS (DN). Plant characteristics including growth and photosynthetic and antioxidant capacities under the four treatments were evaluated.
UNASSIGNED: The results showed that under osmotic stress, the growth of maize seedlings was inhibited, and both the photosynthetic and antioxidant capacities were weakened. Additionally, there were significant increases in the proline and soluble sugar contents and a decrease in seedling relative water content (RWC). However, applying 5-NGS alleviated the impact of osmotic stress on maize seedling growth parameters, particularly the belowground biomass, with a dry mass change of less than 5% and increased relative water content (RWC). Moreover, treatment with 5-NGS mitigated the inhibition of photosynthesis caused by osmotic stress by restoring the net photosynthetic rate (Pn) through an increase in chlorophyll content, photosynthetic electron transport, and intercellular CO2 concentration (Ci). Furthermore, the activity of antioxidant enzymes in the aboveground parts recovered, resulting in an approximately 25% decrease in both malondialdehyde (MDA) and H2O2. Remarkably, the activity of enzymes in the underground parts exhibited more significant changes, with the contents of MDA and H2O2 decreasing by more than 50%. Finally, 5-NGS stimulated the dual roles of soluble sugars as osmoprotectants and energy sources for metabolism under osmotic stress, and the proline content increased by more than 30%. We found that 5-NGS played a role in the accumulation of photosynthates and the effective distribution of resources in maize seedlings.
UNASSIGNED: Based on these results, we determined that foliar application of 5-NGS may improve osmotic stress tolerance in maize seedlings. This study serves as a valuable reference for increasing maize yield under drought conditions.