Study On Quantitative Analysis Of Leaf Surface Aroma Matter And Germplasm Resources Of Tobacco

This paper studied on the method of quantitative analysis to tobacco leaf surface glandular trichome exudates based on the cured tobacco leaves from different ecological regions and green tobacco leaves from the same experiment field. With this method, some genotypes of high density glandular trichome and rich leaf surface exudates were identified from 47 tobacco genotypes which were plant in experiment field of Henan Agricultural University during 2002~2003. Selection index in breeding was also given. The results were as follows:Characteristic absorption of leaves surface CH2Cl2 extractive solution from different tobacco types and genotypes is near 232nm in Ultraviolet area. Main chemical components of leaf surface are close to characteristic absorption. Regression equation from the standard solution was reasonable. The concentration of leaves surface CH2Cl2 extractive solution could be test sensitively at 232nm. The error of regression equation was lower than 5 percent. So the spectrophotometry could be used to test the concentration of leaves surface CH2Cl2 extractive solution.The isoprenoid chemical components were identified as main chemical components of leaf surface exudates in different ecological regions, so the spectrophotometry is suitable in the six ecological regions.Tobacco leaves were extracted with different time length and times by CH2Cl2 solvent. Then the concentration of CH2Cl2 extracted solutions were test by spectrophotometry, and the effect of extraction to microstructure of leaves paraffinic slice were analysed. The best method of extraction leaves surface f exudates was extracting 8 times, every time 2s.From 2002 to 2003, tobacco exudates on leaf surface weight per unit area(EW) varied from 0.007 to 0.16mg/cm2, many EW of genotypes were lower. About two-part genotypes were in 0.007~0.16mg/cm2. The different of EW among the genotypes both were very significant in two years. This suggests that tobacco genotype of high EW can get through breeding progeny selection. But this character was affected easily by entironment, the character was not stable as density of trichome. Some genotypes of high EW were identified: G28, K346, NC628, 8504, 8541, K358, Nongda202, 6388 et al. G28 and 8504 were steadier than the others on the character in two years.In 2002 and 2003, the trichome density of tobacco cutters varied from 500 to 900 per cm2. About a genotypes' trichome density varied from a cm2. The rate of long stalk density and short stalk density varied from 5.88:1 to 16.67:1, of which 60 percent genotypes from 8:1 to 14:1. The difference of trichome density among genotypes was very significant. This suggests that tobacco genotype of high trichome density can get through breeding progeny selection. The density of trichome was stable in two years, and largely determined by genes.Some genotypes of high trichome density were identified: K346, Nongda202, 8502, K149, NC628, 6388, Jinxing6007, K358. Some high trichome density genotypes were stable between two years: K346, NC628, K149, K358. Correlation analysis has been done between glandular trichomes density and leaves surface exudates weight per unit area of two years. Correlation coefficient both was significant. This suggests the genotype of high exudates weight per unit area can get by select genotype of high glandular trichome density.