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Stevia rebaudiana Bertoni is a perennial herb, widely used as a natural sweetener around the globe. The key compounds responsible for its sweetness includes stevioside and rebaudioside-A. In order to improve these steviol glycosides, the present study was initiated to study the effect of induced mutagenesis on growth parameters, steviol glycosides and nuclear DNA content in Stevia rebaudiana Bertoni using ten doses of gamma-rays (5-100 kR). Healthy seeds of 'Madhuguna' variety of Stevia rebaudiana Bertoni developed and maintained at stevia breeding farm, Agrotechnology division, CSIR-Institute of Himalayan Bioresource Technology, Palampur (HP), India were irradiated with ten doses of gamma rays (600 seeds each/dose) ranging from 5 kR to 100 kR (i.e., 5, 10, 15, 20, 30, 40, 50, 60, 80 and 100 kR) using Co60 gamma irradiation chamber at CCS Haryana Agricultural University, Hisar, (Haryana), India. Significant variations were recorded for all the seedling traits studied while major impact was noticed on the seedling after reaching the cotyledonary stage and doses above 40 kR showed absolute mortality of the seedlings. Based on probit analysis, the optimum LD50 dose lies in the range of 20-23 kR. Glycosidic profiling of 296 mutants using high-performance liquid chromatography showed decreased total steviol glycoside content with increased radiation dose. Doses 5 kR and 10 kR, were found to be effective in increasing the overall glycosidic content. A total of 72 promising mutants were also screened for increased rebaudioside-A stevioside ratio. Comparison of nuclear DNA content using flow cytometry revealed a similar decrease in the total nuclear DNA content with increase in dosage of gamma rays. The average genome size at 5, 10, 15, 20 and 30 kR treatments were 2.72, 2.69, 2.68, 2.70 and 2.66 pg as compared to 2.72 pg in control. Mild dose of gamma rays (5 and 10 kR) in stevia were found to be effective in improving the mean steviol glycoside content and may be used in future stevia mutation programmes. [ABSTRACT FROM AUTHOR]

Lavender is a highly valuable medicinal and aromatic perennial shrub lacking superior and stable varieties for varied environments in the western Himalayas. In the present experiment, estimates of genotypic effects and their interaction with the environment under various conditions of Himachal Pradesh were investigated to identify superior and stable genotypes. For that, seven selections with a check were evaluated at four different locations in randomized block design with three replications during 2020 and 2021. The pooled analysis of variance showed that genotypic and environmental main effects were highly significant for all the traits under study while, G×E interaction was significant (p=0.05) for plant height, spike length and spike yield. The highest mean performance for all the traits revealed that location-4 has favourable conditions for lavender cultivation, and LOH15141 followed by LOH15040 were the best performers over all the locations. These high-performing genotypes were clustered together with the check in a major cluster. The stability parameters of the Eberhart and Russell model showed that LOH15141 is stable and superior for both spike yield and essential oil content, further confirmed by GGE biplot analysis. GGE biplot analysis revealed that all the tested locations formed a single mega-environment. The strong positive yield contribution described through Pearson's correlation coefficients and genotypic path diagram states that plant height, number of spikes and spike length were significant contributors to the spike yield and could be used as selection criteria to improve spike yield due to their high heritability and genetic advance. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Stability assessment of selected chrysanthemum hybrids in the North-Western Himalayas." The correction adds Bhavya Bhargava as a co-corresponding author and includes the omitted Funding and Acknowledgements sections. The corrected article can be found online. [Extracted from the article]