Breeding for Cotton Leaf Curl Disease (CLCuD) Resistance

Cotton leaf curl disease (CLCuD) is caused by a Whitefly (B. tabaci) transmitted geminivirus.  It is a major disease of cotton in Africa and South Asia, and has spread to other countries purportedly thru ornamental plants.  It can potentially devastate US cotton where commercial varieties have no resistance to the CLCuD virus.  A recent outbreak devastated the 2015 cotton production in Pakistan.  In combination with other factors, yield was reduced by 30-35%. 

           A joint USDA-Pakistan screening program identified a source of resistance from a US germplasm line designated as MAC7.  Dr. Jodi Scheffler registered reselections from this line, as GVS8 and GVS9 cotton germplasm in the USDA GRIN system.

            A fast-tracked breeding program was initiated to transfer this resistance into commercially acceptable US germplasm.  Screening for the CLCuD virus will be done at the SANIFA Agri Services research station at Rahim Yar Khan in Punjab Province, Pakistan.  The breeding method used is a modified bulk-pedigree using two generations per year.  The winter nursery work will be done at the Cotton Inc. managed research site in Costa Rica.  The paper will discuss how the project is evolving as we move forward based on observations generated in the field.