Comparative Transcriptome Analysis in Eggplant Reveals Selection Trends during Eggplant Domestication

Area of Science:

• Genomics
• Plant Science
• Evolutionary Biology

Background:

• Eggplant (Solanum melongena L.) is a vital crop domesticated in India and southern China.
• Understanding selective pressures during eggplant domestication is crucial for crop improvement.

Purpose of the Study:

• To identify genome regions and genes under selection during eggplant domestication.
• To investigate the roles of artificial and natural selection in shaping the eggplant transcriptome.

Main Methods:

• Comparative transcriptome analysis of cultivated and wild eggplant species.
• Assessment of orthologous genes using nonsynonymous (Ka) to synonymous (Ks) nucleotide substitution ratios.
• Identification of genes under positive selection.

Main Results:

• Generated 44,073–58,677 unigenes across six eggplant accessions.
• Identified 19 genes under positive selection, categorized into four groups.
• One gene (OG12205) potentially linked to fruit traits and eight genes associated with stress/disease resistance were found.

Conclusions:

• Eggplant domestication involved both artificial selection for fruit traits and natural selection for environmental adaptation.
• Identified genes provide insights into the genetic basis of domesticated traits and resources for breeding resistant eggplant varieties.