Manju1, V. Kaur2*,
K. Sharma1? and A. Kumar2 ???
Botany, Baba Mastnath University, Rohtak- 124 021, India
Germplasm Evaluation, ICAR- National?? Bureau of Plant Genetic Resources,
New Delhi-110 012,
Author Email :
Aim: Root architecture
of 220 diverse barley germplasm of Indian (134) and exotic (86) origin was
evaluated for polyethylene-glycol simulated drought stress to identify
drought tolerant genotypes.
Methodology: The evaluation of
root images was done using root scanner (WinRHIZO Pro software v2009).
Variance, Principal Component Analysis (PCA) and Ward?s agglomerative
hierarchical clustering were carried out using SAS software. Correlation
matrices were generated using R.
Results: Analysis of
variance indicated that under stress treatment, differences among the tested
germplasm accessions were highly significant (P0.01) with respect
to total root length (RL), seminal root number (SRN), root surface area
(RSA), root volume (RV), root diameter (RD), lateral root number (LRN) and
root dry weight (RDW) per seedling. LRN was stimulated while other root
traits such as RL, RSA, RV and RDW were significantly inhibited under stress.
PCA indicated that first three components accounted for 80.50% of the total
multivariate variation with PC1 accounting for 44.83%, PC2 for 19.84% and PC3
for 15.87% and it was mainly explained by RL, RSA, RV and RDW. Cluster
analysis grouped 220 barley accessions into five major clusters, with cluster
I being drought susceptible, cluster II being drought tolerant, cluster III
being moderately drought tolerant, Cluster IV being highly drought tolerant
and Cluster V being highly drought sensitive, respectively. ????????????
IC393980, IC082719, IC329556, EC492318, EC578789, EC578790, IC335811 and wild
barley H. marinum ssp. gussoneanum proved to be potential
genetic resources for drought tolerance, which can be used in cereal breeding
program for rain-fed agriculture.
Key words: Barley germplasm, Drought stress, Root architecture, Root
traits, Wild species