Genetic variation in alkaloid accumulation in leaves of Nicotiana

Abstract

Alkaloids are plant secondary metabolites that are widely distributed in Nicotiana species and contribute greatly to the quality of tobacco leaves. Some alkaloids, such as nornicotine and myosmine, have adverse effects on human health. To reduce the content of harmful alkaloids in tobacco leaves through conventional breeding, a genetic study of the alkaloid variation among different genotypes is required. In this study, alkaloid profiles in leaves of five Nicotiana tabacum cultivars and Nicotiana tomentosiformis were investigated. Six alkaloids were identified from all six genotypes via gas chromatograph-mass spectrometry (GC-MS). Significant differences in alkaloid content were observed both among different leaf positions and among cultivars. The contents of nornicotine and myosmine were positively and significantly correlated (R 2 =0.881), and were also separated from those of other alkaloids by clustering. Thus, the genotype plays a major role in alkaloid accumulation, indicating a high potential for manipulation of alkaloid content through traditional breeding.

Variability of phenolic and alkaloid content in different plant parts of Carissa edulis Vahl and Zanthoxylum chalybeum Engl.

“…The abundance of total phenols was higher in Z. chalybeum than C. edulis and the opposite was true for alkaloids. Differences in metabolite abundance have been detected among and within species primarily due to genetic factors [ 30 , 33 , 34 ], environmental effects and their interaction [ 30 , 35 ]. Changing growth conditions, especially nitrogen (N) availability, have been shown to affect phenolic concentrations in plant tissues.…”

“…Most intra-specific variations have been explained by the carbon/nutrient balance hypothesis that predicts leaves to be more responsive to C:N variations and over a very short time period [ 40 ]. Qualitative and quantitative variability due to plant ontogeny, physiological constraints and life-history strategy is also characteristic secondary metabolites [ 21 , 29 , 34 , 39 – 41 ].…”

A Quantitative Real-Time PCR-Based Strategy for Molecular Evaluation of Nicotine Conversion in Burley Tobacco

“…Alkaloids were extracted from lyophilized samples and analyzed as previously described with a minor modification [ 21 , 22 ]. A 300 mg sample was added to 2.0 mL of 5% NaOH in a 50 mL conical flask until mixture, and then incubated for 15 min at room temperature.…”

“…The mass detector was operated by electron impact ionization (EI, 70 eV) with an ion source temperature of 230 °C and an interface temperature of 280 °C. The mass spectrometer was operated in selected ion monitoring (SIM) mode for quantitative analysis [ 21 , 22 ]. The alkaloid content was determined through a calibration curve, and the percentage of nicotine conversion was calculated as: [% nornicotine/(% nornicotine + % nicotine)] × 100 [ 11 ].…”

Endorhizal Fungal Association and Colonization Patterns in Solanaceae

“…The toxicity of these alkaloids to humans and other animals can range from mild irritation to lethality even in small quantities (Chowański et al 2016). The poisonous species in this family include Atropa belladonna L., Hyoscyamus niger L. and Datura stramonium L. The family includes an important economic plant, tobacco (Nicotiana tabacum L.), which contains highly toxic alkaloids such as anabasine, anatabine, nicotine and nornicotine (Sun et al 2013).…”