Background
The stalk traits (stalk diameter (SD), stalk length (SL), rind penetrometer resistance (RPR), and dry matter content (DMC)) are important indicators for measuring lodging resistance.
Results
In this study, 377 inbred lines were used as four stalk-related traits, including SD, SL, RPR and DMC, were investigated at the tasseling, grain filling, and maturity stages in the third segment of maize. 461053 high-quality SNPs which were obtained by whole genome resequencing was used for genome-wide association study. The results showed that 29 significant SNPs related to traits were detected by MLM analysis (P < 9.77×10− 6), related to stalk correlation explaining 7.19% -15.03% of phenotypic variation, among which 4, 1, 4 and 20 SNPs were found related to RPR, SD, SL, and DMC respectively. Most candidate genes are related to plant element structure, signal transduction mechanisms, inorganic ion transport and metabolism, nucleotide transport and metabolism, and transporter enzyme families. Comparing MLM and GLM statistical models, a total of 12 candidate genes were detected repeatedly, with candidate gene Zm00001d014449 being detected 5 times, with a phenotypic variation interpretation rate of 9.95% -10.84%. This gene is mainly expressed in cells with active cell division and tissue differentiation, and is involved in the formation of stalk vascular bundles and the synthesis of cell walls. Another candidate gene Zm00001d005300 encodes the transcription factor MYB44, which regulates the dependence of salt stress signal phosphorylation, can effectively inhibit the accumulation of destructive reactive oxygen species, and has a certain resistance to non-Biotic stress. In addition, this study also found that 10 unknown functional genes can be further Functional verification.
Conclusions
This study helps to deepen the understanding of the genetic basis of maize stalk lodging resistance related traits, and provides theoretical guidance for future maize lodging resistance breeding.