|
Structural variation of leaf rust resistance gene Lr35 in resistant and susceptible bread wheat (Triticum aestivum L.) genotypes
|
| |
|
|
|
Abstract: (4368 Views) |
| Leaf rust is one of the most important diseases of wheat causing grain yield loss in most of the wheat growing areas in the world. Development of resistant cultivars is one of the main approaches to control rust diseases. Understanding the genetic basis of resistance and indentifying resistance genes are essential for developement of resistant cultivars. In this study, three specific primer pairs designed based on NCBI data were used and fragments from Lr35 gene with lengths of 340 to 351 base pairs were amplified. The fragments were then cloned and sequenced. The alignment of Lr35 gene sequence revealed 93% similarity with Lr35 sequence from NCBI. In addition, the sequences showed 93% similarity to Lr21 gene from cosmid No. 69-7-1 clone of Aegilops tauschii, 87% to high molecular weight glutenin A gene from Triticum turgidum, 84% to plastid gene acetyl-CoA carboxylase from T. turgidum as well as bread wheat powdery mildew and cold tolerance genes. The fragments amplified using three primer pairs consisted of one open reading frame with lengths of 162, 156 and 160 base pairs coding proteins with lengths of 54, 52 and 54 amino acids, respectively. Structure analysis of sequences revealed the presence of leucine rich repeats which is a conserved site in plant disease resistance genes. Cluster analysis based on sequences of Lr35 gene amplified using the second primer pair could group genotypes according to their response to leaf rust. Ratios of nonsynonymous (Ka) to synonymous (Ks) nucleotide substitutions indicated the possible role of positive or diversifying selection in nucleotide diversity of this gene. Nucleotide diversity among resistant, moderately resistant and susceptible genotypes could be used to design primers based on SNPs Markers for identification of resistant and susceptible cultivars. |
|
| Keywords: Nucleotide diversity, Plant disease resistance genes, Synonymous substitution and Wheat |
|
|
Full-Text [PDF 513 kb]
(1473 Downloads)
|
Type of Study: Scientific & Research |
Subject:
Special
Received: 2015/02/22 | Accepted: 2015/02/22 | Published: 2015/02/22
|
|
|
|
|
|
|
| Add your comments about this article |
|
|
|
