Chloroplast Genetic Engineering in Crop Plants: Techniques and Applications

Year 2025, Volume: 9 Issue: Special, 239 - 246, 28.12.2025

Talha Raziq

https://doi.org/10.31015/2025.si.10

Abstract

For molecular farming and crop improvement, chloroplast transformation has emerged as a compelling alternative to nuclear genetic modification. In this review we will discuss the biology of plastid genomes, highlighting their polyploidy, prokaryotic transcriptional organization, and maternal inheritance, all of which support high-level, stable, and contained transgene expression. Key components of transformation vectors, including homologous recombination sites and selectable markers, are detailed, alongside strategies for multigene operon construction. The article evaluates delivery methods, primarily biolistics and PEG-mediated protoplast transformation, while addressing technical barriers such as low regeneration efficiency in non model and monocot species. Applications are discussed in tobacco and food crops, with examples ranging from vaccine production to stress tolerance and pest resistance. Limitations such as transformation efficiency, species specificity, and regulatory hurdles are critically assessed. Recent advances in base editing, synthetic biology toolkits, and marker-free systems offer potential pathways toward broader adoption. The review concludes that while chloroplast biotechnology holds clear advantages in expression control and biosafety, further innovation in transformation protocols and genome editing delivery is essential for its practical deployment in diverse crops. This synthesis provides a framework for ongoing research aimed at overcoming the technical and regulatory constraints that currently limit widespread use of chloroplast engineering in agriculture.

Keywords

Chloroplast transformation , Plastid genome engineering , Transplastomic plants , Genetic modification in crops , Molecular farming

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