Identification and Analysis of Glandular Trichomes Density in Different Tobacco Germplasms

In order to select the germplasm resources with high density of glandular trichomes for tobacco breeding and accelerate genetic improvement of the fragrance trait. Tall and short glandular trichomes of 110 materials were observed and analyzed. The variation coefficients of the short, long and total glandular trichomes were 25.4%, 29.3% and 23.4%, respectively, there were extensive variations in the experimental materials. Density of short glandular trichomes, tall glandular trichomes and total glandular trichomes were more 34, 17 and 19 than the contrast materials MSK326, respectively, of which the quantity of shared materials were 11. Overall, density of short glandular trichomes on the upper surface of leaves was greater than the lower surface, density of tall glandular trichomes on the upper surface of leaves was lesser than the lower surface, density of the total glandular trichomes on the upper or lower surface was not consistent, density of tall glandular trichomes was greater than short glandular trichomes, but there were individual specific materials which were mainly local germplasms contrary to the law. The results of cluster analysis showed that, when the threshold is 4, the 110 materials can be divided into 5 categories, except for the special class B, the density of the glandular trichomes of other classes was A > C > E > D. Yunyan116, V2, Honghuadajinyuan, Xilouyan and so on, can provide the reference for breeding as materials with high density glandular trichomes.