Abstract
Chloride is an essential micronutrient in tobacco (Nicotiana tabaccum L.) cultivation. However, large amounts of it have many adverse effects on burning quality of tobacco leaves. The objective of this study was to evaluate the genetic variability among 70 oriental-type tobacco genotypes and determine the genomic regions associated with chloride accumulation rate using mixed linear model (MLM) procedure. A total number of 66 alleles were detected by 26 simple sequence repeat (SSR) loci with an average of 2.53 alleles per locus. A model-based Bayesian approach subdivided 70 tobacco genotypes into the three subgroups. Almost 5.85% of the 325 marker pairs showed a significant level of linkage disequilibrium (P ≤ 0.01). Using MLM procedure, 1 SSR locus (pt30027) from linkage group 13 was identified to be associated with the gene(s) controlling low chloride accumulation in oriental tobacco genotypes. Identified markers could be of great interest in marker-assisted selection in tobacco breeding programs.
Acknowledgment
The authors thank Urmia Tobacco Research Center for their practical help in field experiment and Urmia Institute of Biotechnology about lab facilities.