Comparative transcriptomics analysis at the key stage of maize ear development dissect heterosis

Area of Science:

• Plant genetics and breeding
• Maize (Zea mays L.) biology
• Agricultural science

Background:

• Maize grain yield components like ear length are determined during female inflorescence development.
• Inflorescence meristem (IM) activity positively correlates with yield components.

Purpose of the Study:

• To identify the critical developmental stage of ear heterosis in maize.
• To analyze transcriptomic differences during ear development in Yudan888 and its parent lines.

Main Methods:

• Phenotypic analysis of immature ears from IM to floral meristem (FM) stage.
• Comparative transcriptomics analysis of maize ear development.
• Gene Ontology (GO) enrichment analysis.

Main Results:

• Ear length showed additive inheritance at the IM stage and high parental dominance at the SPM stage.
• Distinct maternal or paternal (DMP) genes were more prevalent than ABF1 genes across developmental stages.
• Overdominance expression of cell redox homeostasis genes was linked to heterosis.

Conclusions:

• The transition from IM to SPM stage is inferred as the onset of ear length heterosis.
• A maize ear length heterosis network was established.
• Findings enhance understanding of maize ear development and heterosis.