The Effects Of Maturity And Wet-bulb Temperature At Different Color Fixing Stage To Quality Of Tobacco Leaves Of CB-1

Experiment is conducted to study the changing of chemical substance contents of the fresh tobacco leaves at different maturity levels, the effects of different maturity levels of tobacco leaves and wet-bulb temperature at different color fixing stage on chemical compositions, appearance quality and economic traits of cured leaves. The results are as follows:The nicotine, total nitrogen, starch and chlorophyll contents of different mature fresh tobacco leaves is significant different and all decreased with maturity level. The total sugar and reducing sugar contents of them has no significant difference. The lower matured leaves have the highest content, followed by less matured, over matured has a minimum level. The total sugar and reducing sugar content of the middle and upper leaves increased with the increasing of the maturity level. The petroleum ether extract and the polyphenol content increased with the increasing of the maturity level.During color fixing stage, starch degraded rapidly first and then degraded slowly. When the wet bulb temperature is 38℃, starch degraded most. followed by wet bulb temperature 39℃, When wet bulb temperature is 37℃starch degraded at the lowest level. The total sugar and reducing sugar contents increased first and decreased then increased again at different wet bulb temperature. The nicotine, total nitrogen content was first increased and then decreased at different wet-bulb temperature.The best treatment for lower leaves is harvesting matured leaves, setting wet-bulb temperature of 38℃at color fixing stage. The chemical compositions are all at suitable level, and its average price, the ratio of middle-high quality leaves are 13.6 yuan / kg and 88.36% respectively. The best treatment for middle leaves is harvesting matured leaves, setting wet-bulb temperature of 38℃at color fixing stage. The chemical compositions are all at suitable level, and its average price, the ratio of middle-high quality leaves are 15.7yuan / kg and 88.37% respectively. The best treatment for lower leaves is harvesting matured leaves, setting wet-bulb temperature of 38℃at color fixing stage. The chemical compositions are all at suitable level, and its average price, the ratio of middle-high quality leaves are 12.9yuan / kg and 89.08% respectively.