Apomixis: oh, what a tangled web we have!

Area of Science:

• Plant biology
• Evolutionary genetics
• Reproductive biology

Background:

• Apomixis, asexual reproduction through seeds, is highly desirable in agriculture for creating clonal crops.
• Maintaining valuable genotypes and heterotic traits without inbreeding depression is a key benefit.
• The genetic basis and evolutionary origins of apomixis remain largely unclear.

Purpose of the Study:

• To explore the evolutionary origins and mechanisms of apomixis.
• To harmonize the three main hypotheses regarding apomixis development.
• To present a model integrating recent advances in understanding apomixis.

Main Methods:

• Review of recent advances in evolutionary perspective of apomixis.
• Incorporation of understanding of endogenous effectors (small RNAs, epigenetics, hormones, protein turnover, cell wall modification).
• Analysis of stress responses (oxidative stress, ROS) as potential triggers.

Main Results:

• Apomixis is an evolutionarily complex trait with multiple potential origins.
• Three working hypotheses exist: asynchronous development, epigenetic regulation, and gene-based inheritance.
• Endogenous and exogenous stresses, including ROS, influence apomixis.

Conclusions:

• A harmonized model is proposed to explain the multifaceted origins of apomixis.
• Apomixis implementation in breeding could revolutionize agriculture.
• Further research is needed to fully elucidate the mechanisms underlying this trait.