Difference between Burley Tobacco and Flue-Cured Tobacco in Nitrate Accumulation and Chemical Regulation of Nitrate and TSNA Contents

Abstract

Tobacco-specific nitrosamines (TSNAs) are harmful carcinogens, with nitrate as a precursor of their formation. Nitrate content is considerably higher in burley tobacco than in flue-cured tobacco, but little has been reported on the differences between types of nitrate accumulation during development. We explored nitrate accumulation prior to harvest and examined the effects of regulatory substances aimed at decreasing nitrate and TSNA accumulation. In growth experiments, nitrate accumulation in burley and flue-cured tobacco initially increased but then declined with the highest nitrate content observed during a fast-growth period. When treating tobacco crops with molybdenum (Mo) during fast growth, nitrate reductase activity in burley tobacco increased significantly, but the NO3-N content decreased. These treatments also yielded significant reductions in NO3-N and TSNA contents. Therefore, we suggest that treatment with Mo during the fast-growth period and a Mo-Gfo (Mo-glufosinate) combination at the maturity stage is an effective strategy for decreasing nitrate and TSNAs during cultivation.

Yield Response, Quality Traits, and Nitrogen-Use Efficiency of a Burley Tobacco Crop Grown in Mediterranean Areas (Southern Italy) as Affected by Intensive N Management

“…Alkaloids content of cured leaves increased significantly up to the highest dose of N fertilization. It was in line (or sometimes less), on average, with what is required by tobacco companies and similar to that reported in previous studies on different kinds of tobacco [50,52,55,59]. Alkaloids contribute to defining the organoleptic properties of tobacco smoke; they influence both its flavor and taste [59].…”

“…Considering that nitrates are substrates for tobacco-specific nitrosamines (TSNA) during the curing period [53,54], this is another reason to recommend to growers not to apply an excessive amount of N fertilizers. Nitrate content measured in the present experiment might already produce in light air-cured (Burley) tobacco very high amount of TSNA [55], which are potentially carcinogenic.…”

Parameters of radish phytomass (Raphanus sativus L.) determined by vermicompost and earthworms (Eisenia fetida)

“…The decrease in nitrate content in time (content of nitrates on 3 and 9 May) occurred in all the treatments. The decline in nitrate content with the following days of the growing season was also presented by Li et al (2017). In their experiments the contents of nitrates in tobacco leaves measured from the 45 th to 75 th day after transplanting varied approximately from 100 mg • kg −1 to 1,250 mg • kg −1 NO 3 − -N. On the contrary, Tabaglio et al (2020) did not record the unambiguous dependence between the nitrate content in lettuce leaves and duration of lettuce growing season in the last 6 days before lettuce harvest.…”

Genotypic Variation in Nitrogen Use-Efficiency Traits of 28 Tobacco Genotypes

“…It is known, for example, that the varietal group Burley demands more N than others groups [11], but has similar yields. There are works that show that the difference of N fertilization is even 4-fold higher for Burley compared to other genotypes [12]. For tobacco genotypes, few works have used numerous genotypes in the study of NUE traits [13,14].…”