Variability and Relationships of Root Traits in a Subset of Induced Barley Mutant Collection

Abstract

Although the role of roots in plant performance and in tolerating environmental stresses is unquestionable, no much emphasize have been given to roots because of difficulty in assessing root traits. Sixteen barley mutant genotypes, a representative sub-set of a barley mutant collection maintained at Akdeniz University, Turkey, two wild-type cultivars, Kaya, Quantum and one exotic cultivar, Baronesse, were evaluated to assess variability and interrelationships in root traits. The material was grown in a container filled with cocopeat-perlite mixture in a randomized complete blocks design with two replicates in a greenhouse. The longest root length, total root length, shoot length, number of primary root, root dry weight, shoot dry weight and root/shoot dry weight ratio were measured on the 7th, 14th and 21st day, respectively following the sowing date of the genotypes. There were statistically significant differences (p< 0.05) among genotypes for all characters studied. The early heading mutant, M-K-1, selected from Kaya, was superior for total root length and the longest root length comparing with the rest of entries whereas Quantum and its mutant, M-Q-54, had generally superior means for most of the traits measured. The highest broad-sense heritability estimated by variance components method (91 %) was obtained for root dry weight in this population. Regarding relationships among the traits, the strongest correlation was obtained between the longest root length and the total root length (r=0.953**). It was finally concluded that the mutants selected for above-ground characters are also of significant variability for root traits as part of the mutation spectrum.