Regulations under consideration by the U.S. Food and Drug Administration and the World Health Organization propose that nicotine concentration in tobacco (Nicotiana tabacum L.) should be lowered to non-addictive levels (0.3 to 0.5 mg g −1 ). The proposed standards are 90 to 95% lower than the nicotine concentration typically documented in commercially available cultivars. Research was conducted in six environments to evaluate two cultivars with normal alkaloid levels (K326 and NC95) and four genotypes with low alkaloid levels (DH16A, DH22A, DH32, and LAFC53). Each cultivar and genotype was paired with three N application rates: 70, 85, and 100% of the recommended rate. As N application declined, so too did cured leaf yield and nicotine, anabasine, and anatabine concentration in K326 and NC95. These factors were generally not affected by N application in the low alkaloid genotypes. In contrast, LAFC53 consistently produced the lowest cured leaf quality, value, and reducing sugar concentration when compared to all other cultivars. This observation demonstrates that K326 isolines are agronomically superior to LAFC53. Despite reductions in nicotine, the lowest documented concentration was still 10fold greater than the proposed minimum (LAFC53). Nitrogen did not influence the measured parameters as much as genetics; therefore, additional research that involves other agronomic practices is warranted. In addition, further genetic manipulation will be required to meet the standards proposed by regulatory groups.

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Over the last two decades, burley tobacco (Nicotiana tabacum L.) production has declined by 5,300 acres in western North Carolina (North Carolina Department of Agriculture and Consumer Services, 2005; USDA-NASS, 2019). The loss of burley tobacco has left a void in the agricultural economy. Cigar wrapper tobacco types, such as Pennsylvania seedleaf (PA41) and Connecticut broadleaf, may be suitable replacements for burley because of their overlapping production practices. Cigar tobacco has not been produced in western North Carolina; therefore, knowledge gaps exist regarding its growth habits in the region. The objective of this study was to quantify the days to flower removal, yield, and grade distribution of six cigar tobacco varieties. 2 METHODS AND MATERIALS In 2019, experiments were initiated at the Mountain Research Station in Waynesville, NC (35.48N,-82.96W) and the Upper Mountain Research Station in Laurel Springs, NC (36.39N,-81.30W). Treatments were arranged This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Organic flue-cured tobacco (Nicotiana tabacum L.) accounts for more than US$39 million in farm gate revenue in North Carolina (USDA-NASS, 2017). Commercial production has not been free of challenges, specifically in reference to axillary bud (sucker) control because of the prohibition of synthetic plant growth regulators. Organic sources of fatty alcohol have been approved for application; however, the USDA National Organic Standards Board has recently scrutinized their use (Suchoff, Vann, & Short, 2019). Without options for chemical sucker control, the cost of production may increase by US$400 to 800 acre -1 (Short, Suchoff, Vann, & Fisher, 2020). To ensure the longevity and success of organic tobacco production, alternative organic options are needed. Pelargonic acid (PA) (nonanoic acid) is currently certified for organic tobacco production in the United States but has not been evaluated by a Cooperative Extension. Our objectives were to quantify the phytotoxicity and sucker control efficacy of various application rates of PA.