Effect of Reactive Oxygen Scavenger N,N′-Dimethylthiourea (DMTU) on Seed Germination and Radicle Elongation of Maize

Abstract

Reactive oxygen species (ROS) are an important part of adaptation to biotic and abiotic stresses and regulate seed germination through positive or negative signaling. Seed adaptation to abiotic stress may be mediated by hydrogen peroxide (H2O2). The effects of the ROS scavenger N,N′-dimethylthiourea (DMTU) on maize seed germination through endogenous H2O2 regulation is unclear. In this study, we investigated the effects of different doses of DMTU on seed endogenous H2O2 and radicle development parameters using two maize varieties (ZD958 and DMY1). The inhibitory effect of DMTU on the germination rate and radicle growth was dose-dependent. The inhibitory effect of DMTU on radicle growth ceased after transferring maize seeds from DMTU to a water medium. Histochemical analyses showed that DMTU eliminated stable H2O2 accumulation in the radicle sheaths and radicles. The activity of antioxidant enzyme and the expression of antioxidant enzyme-related genes (ZmAPX2 and ZmCAT2) were reduced in maize seeds cultured with DMTU compared with normal culture conditions (0 mmol·dm−3 DMTU). We suggest the use of 200 mmol·dm−3 DMTU as an H2O2 scavenger to study the ROS equilibrium mechanisms during the germination of maize seeds, assisting in the future with the efficient development of plant growth regulators to enhance the seed germination performance of test maize varieties under abiotic stress.

A Phenotypic Extraction and Deep Learning-Based Method for Grading the Seedling Quality of Maize in a Cold Region

“…However, the slow warming of the tillage soil and stage of low temperature after sowing often lead to seed germination and seedling formation challenges, including reduced and delayed seedling emergence, decreased seedling rate, and an increased proportion of weak seedlings. In severe cases, seeds completely lose their viability, resulting in a large area without seedlings [14][15][16]. Ultimately, these factors make it difficult to establish high-quality maize populations in the region, causing a major bottleneck for maize mechanization and efficient production.…”

Transcriptome Analysis Reveals POD as an Important Indicator for Assessing Low-Temperature Tolerance in Maize Radicles during Germination

“…Radicle growth, which is a main component of seed embryo germination, is considerably affected by low temperature and water stress during seed germination and seedling emergence. Radicle length is widely used as a key indicator for evaluating abiotic stress tolerance to low temperature and drought in crops such as maize [30], rice [31], and cotton [32,33]. However, the effects of TS on maize seed germination and seedling stage have been extensively studied in terms of phenotype [34], physiology and biochemistry [35], transcriptome [36], and metabolome [37].…”