Diallel Analysis for Nicotine Content and Leaf Thickness in Hookah and Chewing Tobacco (Nicotiana Rustica L.)

A ten-parent diallel study conducted on the genetic architecture of nicotine content and leaf thickness in hookah and chewing tobacco (Nicotiana rustics L.) showed that mean squares due to general and specific combining ability were significant, suggesting the importance of both additive and dominance components. The line Farrukhabad was identified as best general combiner for simultaneous improvement In both characters. The crosses T 238×Tangna, Hazro×Tangua, and Farrukhabad×NP 222 for nicotine content and Chaithar×M₄, Farrukhabad×Tangua, and Famikhabad×Peshawar Snuff for leaf thickness were the best specific combinations for nonfixable components. Low narrow sense heritability was observed for both characters. Numerical analysis for leaf thickness revealed asymmetrical gene distribution and uneaqual allele frequency. Reciprocal recurrent selection or diallel selective mating, which exploits both fixable and nonfixable components, has been suggested for the improvement of these traits.