Multi-environment evaluation of Clary sage (Salvia sclarea L.) selections for yield and essential oil traits under Western Himalayan conditions

Abstract

Clary sage is an important aromatic herb that has a high potential for commercial cultivation under the diversified climates of the Western Himalayas. The present study was carried out to understand the performance of genotypes and their interaction with the varied environments prevalent in the Western Himalayas and to identify stable and best-performing genotypes. In the present experiment, ten superior selections were evaluated in four different environments as multi-location trials in a randomized block design with three replications during 2021 and 2022. The pooled analysis of variance revealed significant variations for genotypes, environments, and genotype × environment interaction for all the studied traits. The highest mean performance suggests that Env-1 has the most suitable conditions for clary sage cultivation. The genotypes CSIR-IHBT-SS-07 and CSIR-IHBT-SS-09 were found to be the best performers for fresh inflorescence weight (418.73 g/plant) and essential oil content (428.91 mg/Kg), respectively. The results of Eberhart and Russell’s regression-based model confirm that the genotype CSIR-IHBT-SS-07 is a stable and superior genotype for the economically important traits. Further, the gas-chromatography mass spectroscopic characterization of essential oil disclosed that CSIR-IHBT-SS-07 was unique in terms of the highest sclareol content (23.39–45.17 %) across all the test environments. Genotype + Genotype × Environment biplot analysis confirmed that all the test environments form a single mega-environment. The study is a pioneer in unraveling the stability response of clary sage in Western Himalaya and provides a strong base for the identification of superior genotypes and selection strategy for future genetic improvement programs of clary sage.