Analysis on Solanesol Content and Genetic Diversity of Chinese Flue‐Cured Tobacco (Nicotiana tabacum L.)

Solanesol is an important pharmaceutical intermediate that also affects the quality of tobacco ( Nicotiana tabacum L.) leaves. To explore novel applications of tobacco leaves and to broaden the genetic basis of flue‐cured tobacco breeding varieties, the solanesol content of 168 Chinese flue‐cured tobacco germplasm resources, planted at four geographical regions of China in 2014 and 2015, was determined using ultra‐performance liquid chromatography. Solanesol content and genetic diversity were analyzed using additive main effects and multiplicative interaction model (AMMI) and simple sequence repeat (SSR) markers. The results indicated that solanesol content of flue‐cured tobacco ranged from 0.70 to 4.13% and the mean content of samples from the northern regions (2.60%) were higher than that from the southern regions (1.67%) of China. Genotypes, environments, and their interactions all had significant impacts on the solanesol content of tobacco leaves. Additionally, high‐solanesol varieties Dashuba2106, Changboyan, and Heiyeyan and low‐solanesol cultivars Zhongyan90, CF90NF, Zhongyan102 had the highest hereditary stability. These 168 accessions were divided into introduced (Y), breeding (X), and local (D) groups according to origins. Using 69 SSR primer pairs selected from 1196 primer combinations, we scored 271 alleles, of which 229 (84.50%) were polymorphic. Shannon's index, Nei's index, and polymorphism information content value were 0.8006, 0.4613, and 0.4014, respectively, suggesting a wide genetic basis of these 168 germplasm resources. Among the three groups, the D group showed the richest genetic diversity, while the Y group exhibited the lowest genetic diversity. The Y and X groups had the highest genetic similarity (0.9657), followed by X group versus D group (0.9462) and Y group versus D group (0.9019). Findings in this study should have great importance for future exploitation and utilization of solanesol from tobacco leaves.