DEVELOPMENT OF STEM RUST RESISTANT TRANSGENIC WHEAT PLANTS THROUGH THE UTILIZATION OF THE PR2 GENE

Authors: Kamran Ali, Shazia Anwer Bukhari, Bushra Sadia, Mahmood-ur-Rahman
Journal: Journal of Animal and Plant Sciences (JAPS)
ISSN: 1018-7081 (Print), 2309-8694 (Online)
Volume: 36  Issue: 5  
Year: 2026
DOI: https://doi.org/10.36899/JAPS.2026.5.0109
URL: https://doi.org/https://doi.org/10.36899/JAPS.2026.5.0109
Publisher: Pakistan Agricultural Scientists Forum

Abstract:
<p style="margin-top: 12pt; line-height: normal; background: white; text-align: justify;"><span style="font-family: 'Times New Roman', serif; color: windowtext; font-size: 12pt;">Wheat (<em style="mso-bidi-font-style: normal;">Triticum aestivum </em>L.) productivity is severely constrained by biotic stresses, among which stem rust remains a major threat to global food security. In this study, we developed wheat line overexpressing the pathogenesis-related gene 2 (<em style="mso-bidi-font-style: normal;">PR2</em>) gene to build innate antifungal defenses. The <em style="mso-bidi-font-style: normal;">PR </em>gene<em style="mso-bidi-font-style: normal;"> </em>coding sequence was cloned into the pCB-<em style="mso-bidi-font-style: normal;">PR2</em>-P2A-GUS expression vector and introduced into embryogenic calli of the TD-1 cultivar via biolistic transformation. Regenerated plantlets were subjected to rigorous molecular analysis, including PCR and RT qPCR, confirming stable genomic integration and ~35-fold upregulation of <em style="mso-bidi-font-style: normal;">PR2 </em>gene<em style="mso-bidi-font-style: normal;"> </em>transcripts relative to non-transgenic controls. Histochemical &beta;-glucuronidase (GUS) assays revealed spatial and temporal expression patterns across callus and developing seeds, indicating robust promoter-driven activity. Functional evaluation under natural pathogen exposure demonstrated marked reduced stem rust pustule formation in transgenic lines, validating the antifungal efficacy of &beta;-1,3-glucanase in plants. <em style="mso-bidi-font-style: normal;">In silico</em> allergenicity analysis showed minimal similarity to known wheat allergens, supporting the biosafety of the transgene. These results established a comprehensive framework for <em style="mso-bidi-font-style: normal;">PR2</em> gene-mediated disease resistance, integrating molecular validation with phenotypic assessment. Future field trials will elucidate the durability of stem rust resistance and yield stability, providing strategic insights for wheat breeding programs.</span></p>

Keywords: Stem resistance, PR2 gene, Transgenic wheat, Wheat transformation