Stability of Alkaloid Production in Flue‐Cured Tobacco

Abstract

Alkaloid production in flue‐cared tobacco (Nicotiana tabacum L.) genotypes must be within an established acceptable level for the genotypes to be released as cultivars. The objectives of this study were to examine the stability of alkaloid production in cultivars and advanced breeding lines relative to standards set in the Regional Minimum Standards Program. Stability of alkaloid production was examined using data from the Regional Farm Test entries (1986– 1988) and the North Carolina Official Variety Tests (1979–1983). Averaged across 55 environments, the two check cultivars did not differ in nicotine or nornicotine production; however, ‘NC 95’ produced higher levels of anabasine and anatabine and had a higher ratio of total secondary alkaloids to total alkaloids (TSA/TA) than ‘NC 2326’. As indicated by the coefficients of variation, there were stability differences for nornicotine, anabasine, and anatabine production as well as TSA/TA in the Regional Farm Tests but none for nicotine production. In the North Carolina Official Variety Tests, there was a significant cultivar ✕ year interaction for nicotine production and a significant location effect for nornicotine production. The unstable production of secondary alkaloids suggests that TSA/TA should be examined across both years in which the entries are in the program before rejection or acceptance.