Developmental and genetic variation in nuclear microsatellite stability during somatic embryogenesis in pine

Area of Science:

• Plant Biotechnology
• Molecular Biology
• Forest Genetics

Background:

• Genotypic instability is a common issue in plants regenerated via tissue culture, often linked to in vitro-induced stress.
• Understanding genetic instability is crucial for optimizing plant propagation and breeding programs.

Purpose of the Study:

• To investigate if in vitro-induced genetic instability differs among Pinus sylvestris families.
• To determine the influence of genetic instability on adaptation to in vitro conditions and embryo development.

Main Methods:

• Comparison of genetic stability at four nuclear microsatellite loci in embryogenic cultures and zygotic embryos of Pinus sylvestris.
• Analysis of genetic stability across 10 different families.

Main Results:

• Significant variation in genetic stability was observed among Pinus sylvestris families.
• Six out of 10 families exhibited similar genetic stability between somatic and zygotic embryos.
• The remaining families showed significantly higher mutation rates during somatic embryogenesis.
• Families with lower genetic stability during culture establishment displayed higher embryogenic potential.
• Conversely, genetically unstable families experienced suppressed embryo development.

Conclusions:

• In vitro stress induces varying levels of genetic instability across Pinus sylvestris families.
• Genetic instability impacts both embryogenic potential and embryo development, suggesting a trade-off.
• The observed mutation rates may reflect adaptive plasticity in widely distributed species like Pinus sylvestris.