Effects of Selection on Genetic Parameters of Secale montanum Based on Seed Storage Protein Marker

Document Type: Research and Full Length Article

Authors

1 Natural Resources Gene Bank, Research Institutes of Forests and Rangelands, Tehran

2 Natural Resources Gene Bank, Research Institutes of Forests and Rangelands, Tehran,

3 Azad University of Karaj, Karaj

Abstract

Secale montanum is one of the important perennial grasses growing
naturally in arid to semiarid pastures and rangelands, with a typical Mediterranean
climate, in northern and western Iran at altitudes of 800-2900 m. In this paper, seed
storage protein profiles of nine wild populations of S. montanum from different
regions of Iran and their phenotypically superior progenies as well as a multi-origin
polycross (PLC) were studied. High levels of polymorphism were observed over all
populations with the average number of bands and average heterozygosity. Superior
progeny of different populations showed less genetic variability than wild parents in
terms of band diversity, whereas PLC samples showed extremely high values of
genetic parameters. Two locally common bands were observed in almost all wild
parent populations, which are missing in superior progeny of different populations
and PLC. These results provide highly support for the hypothesis that neutral genetic
diversity has been reduced or inadvertently lost via artificial selection. Among wild
parent populations and their superior progenies significant differences were observed
in expected heterozygosity suggesting that more intensive breeding practices may
have resulted in a further erosion of genetic variability. Neighbor-joining cluster
analysis showed that wild populations and the phenotypically superior progeny of
different populations were separated into two groups. This suggests that founder
effects and subsequent selection have had more effect on the genetic differentiation
between these accessions than geographical separation. This technology, seed storage
protein profiling, has great potential for use in breeding programmes.

Keywords