四川雪茄系列品种烟碱转化率及品种纯化效果.

【Objective】 The present paper aimed to optimize the composition of alkaloid in Sichuan cigar and realize the quality improvement and harm reduction of cigar, the conversion degree of nicotine to nornicotine and the distribution of nicotine conversion rate between plants among the main cigar varieties were determined, and variety purification was carried out according to the conversion traits of nicotine.【Method】 Dexue 1, Dexue 3, Dexue 4, Dexue 5, Dexue 7 and Shiyan 1 were used as test materials. The content of alkaloids and TSNAs in the middle leaves of the tested varieties were determined and analyzed. The main cultivars in Sichuan (Dexue 4, Dexue 7 and Shiyan 1) were purified by early conversion stimulation and converter identification. 【Result】 (i) The alkaloid composition and contents in Sichuan cigar varieties were significantly different, and there were different degrees of nicotine conversion in different varieties, and the distribution of nicotine conversion rate between plants was quite different. The nicotine conversion problem of Dexue 5 was prominent. The proportion of converters in the tested group was 100%, and all converters were high converter. There were a large number of nicotine converters in Shiyan 1, among which the low converters were the majority, accounting for 37.9% of the total population. The problems of nicotine conversion in Dexue 1 and Dexue 3 were relatively less serious with all the tested plants being low converters. The conversion rate of Dexue 4 and Dexue 7 were 48% and 30%, respectively. (ii) Based on the early conversion stimulation and converter identification of Dexue 4, Dexue 7 and Shiyan 1, the non-converters were strictly selected for self-fertilize, and the corresponding purified species seeds were obtained. Compared with the corresponding conventional varieties, the nicotine content and nicotine conversion rate of purified variety were significantly reduced, the NNN contents and the total amount of TSNAs were significantly reduced, and the NNN contents of Dexue 7 was reduced from 2615.27 ng/g to 442.67 ng/g, the total amount of TSNAs decreased from 3602.46 ng/g to 1327.24 ng/g, and the NNN contents of Dexue 4 and Shiyan 1 decreased from 3235.76 and 3940.32 ng/g to 945.32 and 1315.40 ng/g, the total amount of TSNAs decreased from 5658.51 and 6669.89 ng/g to 2889.81 and 2840.12 ng/g. The purified variety had better cigar flavor. 【Conclusion】 Sichuan cigar varieties have different degree of nicotine conversion problems. By early conversion stimulation and converter identification and strictly selecting non-converters to self-fertilize for the purification, conversion rate and tobacco-specific nitrosamine contents can be effectively reduced, the quality and safety of cigar can be improved. [ABSTRACT FROM AUTHOR]