To the extent of our knowledge, applications of DNA markers in marker-assisted breeding of cotton are handicapped due to low genetic diversity in cotton germplasm. Cotton leaf curl disease, a disease of viral origin, has substantially depressed cotton production in Pakistan, and this disease is also an emerging threat to the neighboring cotton-growing countries like China and India. | Turkish Journal of Botany Turk J Bot (2015) 39: 1033-1041 © TÜBİTAK doi: Research Article Estimating genetic diversity among selected cotton genotypes and the identification of DNA markers associated with resistance to cotton leaf curl disease 1 1 1 1,* 2 Ammad ABBAS , Muhammad Atif IQBAL , Mehboob-ur RAHMAN , Andrew H. PATERSON Plant Genomics & Molecular Breeding Lab, National Institute for Biotechnology and Genetic Engineering, PIEAS Campus, Faisalabad, Pakistan 2 Plant Genome Mapping Laboratory, University of Georgia, Athens, Georgia, USA Received: Accepted/Published Online: Printed: Abstract: To the extent of our knowledge, applications of DNA markers in marker-assisted breeding of cotton are handicapped due to low genetic diversity in cotton germplasm. Cotton leaf curl disease, a disease of viral origin, has substantially depressed cotton production in Pakistan, and this disease is also an emerging threat to the neighboring cotton-growing countries like China and India. The present study was designed to identify DNA markers, predominately simple sequence repeats (SSRs), associated with tolerance and/or resistance to the disease. Based upon 2 years of disease-screening field experiments, a total of 10 cotton genotypes (five highly tolerant, four highly susceptible, and one immune) of diverse origin were selected from the available cotton germplasm (~1200 accessions) of the National Institute for Biotechnology and Genetic Engineering, Faisalabad, Pakistan. In total, 322 SSRs derived from bacterial artificial chromosome end sequences of Gossypium raimondii (one of the progenitor species of cultivated tetraploid cotton) were screened. Out of these, 65 primer pairs were found polymorphic, and the extent of genetic similarity was in the range of to . A similarity matrix was used for studying their phylogenetic relationship using unweighted pair-group .
