Combining transcriptome and metabolome analyses to reveal the response of maize roots to Pb stress.

As a major food crop, maize (Zea mays L.) is facing a serious threat of lead (Pb) pollution. Research into its Pb tolerance is crucial for ensuring food security and human health, however, the molecular mechanism underlying the response to Pb remains incompletely understood.

Transcriptomics Combined with Physiology and Metabolomics Reveals the Mechanism of Tolerance to Lead Toxicity in Maize Seedling.

Lead (Pb) exposure can induce molecular changes in plants, disrupt metabolites, and impact plant growth. Therefore, it is essential to comprehend the molecular mechanisms involved in Pb tolerance in plants to evaluate the long-term environmental consequences of Pb exposure. This research focused on maize as the test subject to study variations in biomass, root traits, genes, and metabolites under hydroponic conditions under Pb conditions.

Flavonoid metabolism plays an important role in response to lead stress in maize at seedling stage.

Background: Pb stress, a toxic abiotic stress, critically affects maize production and food security. Although some progress has been made in understanding the damage caused by Pb stress and plant response strategies, the regulatory mechanisms and resistance genes involved in the response to lead stress in crops are largely unknown.

Results: In this study, to uncover the response mechanism of maize to Pb stress phenotype, physiological and biochemical indexes, the transcriptome, and the metabolome under different concentrations of Pb stress were combined for comprehensive analysis.

Combined linkage mapping and association analysis reveals genetic control of maize kernel moisture content.

The free moisture in crop kernels after being naturally dried is referred to as kernel moisture content (KMC). Maize KMC reflects grain quality and influences transportation and storage of seeds. We used an IBM Syn10 DH maize population consisting of 249 lines and an association panel comprising 310 maize inbred lines to identify the genetic loci affecting maize KMC in three environments.

A combination of linkage mapping and GWAS brings new elements on the genetic basis of yield-related traits in maize across multiple environments.

Using GWAS and QTL mapping identified 100 QTL and 138 SNPs, which control yield-related traits in maize. The candidate gene GRMZM2G098557 was further validated to regulate ear row number by using a segregation population. Understanding the genetic basis of yield-related traits contributes to the improvement of grain yield in maize.

Genome-wide association studies and QTL mapping uncover the genetic architecture of ear tip-barrenness in maize.

Ear tip-barrenness (ETB) phenotype threatens crop yield, because it reduces the kernel number per ear. The genetic basis of ETB in maize remains largely unknown. Herein, a genome-wide association study (GWAS) and quantitative trait loci (QTL) mapping were jointly applied to identify the significant genetic loci interrelated with ETB.

Combined GWAS and QTL analysis for dissecting the genetic architecture of kernel test weight in maize.

Kernel weight in a unit volume is referred to as kernel test weight (KTW) that directly reflects maize (Zea mays L.) grain quality. In this study, an inter-mated B73 × Mo17 (IBM) Syn10 doubled haploid (DH) population and an association panel were used to identify loci responsible for KTW of maize across multiple environments.

Combination of multi-locus genome-wide association study and QTL mapping reveals genetic basis of tassel architecture in maize.

Maize tassel architecture is a complex quantitative trait that is significantly correlated with biomass yield and grain yield. The present study evaluated the major trait of maize tassel architecture, namely, tassel branch number (TBN), in an association population of 359 inbred lines and an IBM Syn 10 population of 273 doubled haploid lines across three environments. Approximately 43,958 high-quality single nucleotide polymorphisms were utilized to detect significant QTNs associated with TBN based on new multi-locus genome-wide association study methods.

Multi-Locus Genome-Wide Association Study Reveals the Genetic Architecture of Stalk Lodging Resistance-Related Traits in Maize.

Stalk lodging resistance, which is mainly measured by stem diameter (SD), stalk bending strength (SBS), and rind penetrometer resistance (RPR) in maize, seriously affects the yield and quality of maize ( L.). To dissect its genetic architecture, in this study multi-locus genome-wide association studies for stalk lodging resistance-related traits were conducted in a population of 257 inbred lines, with tropical, subtropical, and temperate backgrounds, genotyped with 48,193 high-quality single nucleotide polymorphisms.

A genetic study of the regeneration capacity of embryonic callus from the maize immature embryo culture.

We carried out a study of regeneration capacities of embryonic callus from maize immature embryo culture with 144 different inbred lines of natural groups from different countries, and found that the regeneration capacity was affected by three factors: environment, genotype and the interaction between the environment and genotype. We found that green embryonic callus rate (GCR), embryonic callus differentiating rate (CDR) and the plantlet number of embryonic callus regeneration (CPN) have significant positive correlations with each other, and they all have significant negative correlations with embryonic callus browning rate (CBR). Moreover, embryonic callus cloning index for the first subculture (CCI1) and embryonic callus cloning index for the second subculture (CCI2) have a significant positive correlation with each other, and CCI2 is positively correlated with green GCR, and is negatively correlated with CBR.