Cisgene stacking for the creation of late blight-resistant potatoes

Dr. Md. Monirul Islam: Developing late blight-resistant potatoes through cisgene stacking is an innovative approach that harnesses genetic engineering to create potato varieties with enhanced resistance to late blight (Phytophthora infestans). Late blight is a devastating disease that can cause significant crop losses in potato production. Cisgene stacking offers a targeted and sustainable solution to combat this disease while minimizing potential environmental and regulatory concerns associated with traditional genetic modification.

Cisgenes are genes sourced from the same or closely related species, ensuring that the genetic material introduced into the potato plant is natural and not from unrelated organisms. This approach reduces the likelihood of unintended side effects. Scientists identify naturally occurring late blight resistance genes in wild or cultivated potato relatives that have evolved to combat the disease. The late blight-resistant genes are isolated and characterized to ensure they are effective at conferring resistance to Phytophthora infestans. The identified cisgenes are introduced into cultivated potato varieties that are susceptible to late blight. This is typically done using genetic engineering techniques such as Agrobacterium-mediated transformation or particle bombardment. Multiple cisgenes with different modes of resistance may be stacked together in a single potato variety. This stacking approach enhances resistance and reduces the risk of the pathogen evolving to overcome a single resistance mechanism.

The genetically modified potato varieties are extensively tested in controlled field trials to assess their resistance to late blight, as well as their agronomic performance, yield, and other traits. Before commercial release, the genetically modified potatoes must go through rigorous safety assessments and regulatory approval processes to ensure they are safe for human consumption and the environment. Once regulatory approvals are obtained, late blight-resistant potato varieties can be commercialized, benefiting farmers by reducing the need for chemical fungicides and reducing crop losses due to late blight.

Benefits of Cisgene Stacking for Late Blight Resistance:

  1.  Enhanced Resistance: Cisgene stacking can provide robust and durable resistance to late blight, reducing the risk of pathogen evolution.
  2.  Reduced Chemical Use: Farmers can reduce their reliance on chemical fungicides, promoting environmentally friendly and sustainable agriculture.
  3.  Crop Yield and Quality: Improved resistance can lead to higher potato yields and improved crop quality.
  4.  Reduced Environmental Impact: Minimized chemical use and crop losses contribute to a reduced environmental footprint.
  5.  Food Security: Late blight-resistant potatoes can enhance food security by reducing crop losses and improving potato availability.

Cisgene stacking is an example of precision breeding that can address important agricultural challenges while addressing some of the concerns associated with genetic engineering. However, public acceptance, regulatory approval, and responsible deployment are essential aspects of its successful implementation in agriculture.

Writer: Senior Scientist, ASRBC, ACI Seed