Effects of meteorological factors on aroma precursors contents of high aroma flue-cured tobacco

It is important to explore correlation between meteorological factors and aroma precursors for cultivation of high aroma flue-cured tobacco varieties. In this study, the contents of main aroma precursors of the high aroma flue-cured tobacco variety ‘Yuyan 11’ and conventional flue-cure tobacco variety ‘Yunyan 87’ at 5 different experimental locations (with different meteorological conditions due to different altitudes and latitudes) were analyzed to determine the effects of meteorological factors on aroma precursors contents of high aroma flue-cured tobacco. The correlations between aroma precursors contents and 6 meteorological factors (average temperature, relative humidity, sunshine duration, rainfall, evaporation and cloudiness) at rooting stage, vigorous growth and mature stage of tobacco, a total of 18 meteorological factors, were also determined using the grey relational degree method. The results indicated that the main aroma precursors contents of ‘Yuyan 11’ at each location was significantly higher than those of ‘Yunyan 87’. The contents of tobacco leaf carotenoids in low latitude locations were lower than those in high latitude locations. Polyphenol content increased gradually with decreasing altitude and increasing sunshine hour at maturity stage. The content of leaf trichome exudates in high latitude locations was higher than that in low-latitude locations, and it was highest in Henan Lushi. The contents of carotenoid in the leaves of ‘Yuyan 11’ and ‘Yunyan 87’ were influenced more by sunshine hour at maturity stage and average temperature at other growth stages. Sunshine duration during the growth period greatly influenced the content of polyphenols. Grey correlation trend for the contents of petroleum ether extracts and leaf trichome exudates with meteorological conditions for ‘Yuyan 11’ and ‘Yunyan 87’ were significantly different. The content of petroleum ether extract of ‘Yuyan 11’ was more influenced by sunshine hour during the growth period, but that of ‘Yunyan 87’ was more influenced by average temperature. The content leaf trichome exudates of ‘Yuyan 11’ was more influenced by sunshine hour at maturity stage and average temperature during vigorous growth stage, but that of ‘Yunyan 87’ was more influenced by average temperature at rooting stage, and by evaporation and average temperature at maturity stage. The effect of sunshine hour at maturity stage and that of average temperature at vigorous growth stage on the quality of high aroma flue-cured tobacco variety ‘Yuyan 11’ should be fully considered when choosing a planting area.