Abstract
Aim:
Identification of high breeding value donor lines harbouring tolerance to
moisture stress from diversity stock of 443 genotypes of Brassica juncea.
Methodology: Germplasm stock of 443 Indian mustard (Brassica
juncea L.) genotypes, comprising introgression lines, land races, old
cultivars and advance breeding lines, were evaluated under two environments
viz., irrigated and rainfed conditions to check the variability for yield and
related traits. Statistical software META-Rver 6.0 (Multi Environment Trial
Analysis using R) was used for computation of Best Linear Unbiased
Predictions, Analysis of Variance (ANOVA), Genetic Correlations and
Heritability. Drought susceptibility index and per cent seed yield reduction
under rainfed conditions were used as indicators to determine moisture stress
tolerance in genotypes.
Results:
The variability for moisture stress tolerance has been unravelled in a
diverse genetic stock of Brassica juncea under two environments:
irrigated and rainfed. For high prediction accuracy, the ranking of genotypes
was done based on Best Linear Unbiased Predictions for seed yield and its
component traits. PBR-378, RGN-329, RB-73, RB-50 and PBR-422 and Giriraj were
identified as moisture stress tolerant genotypes. One land race Sahib 36 and
three introgression lines viz., MCP 12-211, PTJ-3-69 and MSC-3 have also been
identified as potential genetic resources for moisture stress tolerance.
Principal component analysis based on biplots depicted specific distribution
of variables for each environment.
Interpretation: This study led to the identification of
potential donors for moisture stress tolerance with high predictive accuracy.
Low drought susceptibility index and high breeding value in a land race and
three introgression lines derived from Erucastrum cardaminoides, B.
tournefortii and B. carinata emphasized their utilization as
potential genetic resources to breed for moisture stress tolerance in B.
juncea.
Key words: Brassica juncea, Drought susceptibility
index, Moisture stress, Seed yield
|