Physical Properties of Non-Fermented and Fermented Tobacco of Burley Varieties and Lines (original) (raw)
The physical properties of the raw material are an objective indicator of the quality of the tobacco leaves and a reflection of their structure. They are very closely related to the structure and the content of the organic matter in the leaf. The selection of the variety, the applied agricultural techniques, the environmental conditions during the vegetation period, the leaf position, the technological maturity, as well as the conditions during drying, are important factors that have a strong impact on the formation of the physical and technological properties of the tobacco raw material. The tests included 4 varieties and 2 lines, namely: L-8 (control variety, Zimbabwe), Kentucky-22 (USA), B-963 (Bulgaria) and B-1246 (Bulgaria), all in fertile form, as well as the male sterile hybrid lines B-204/15 CMS F 1 and B-206 A/15 CMS F 1. The test was planted in 4 repetitions with a planting density of 90×50 cm according to the Randomized Block System method. After the evaluation of the tobacco according to the current Rulebook for qualitative evaluation of raw tobacco, we separated tobacco material from the middle belt, in order to get an insight into the differences of the physical properties from the examined varieties and lines in the non-fermented and fermented tobacco. The percentage portion of the main (mid) rib, the thickness of the leaves, and the materiality of the leaves, are important physical indicators of the quality of the raw material, and from the obtained results we can point out the line B-206 A/15 CMS F 1 , where the average content of the main rib of the nonfermented tobacco leaf is within the limits of 26.82%, in the line B-206 A/15 CMS F 1 there is up to 25.13% portion of the main rib of the fermented leafs. The leaf portion in the newly obtained line is within the range from 73.18% (non-fermented tobacco leaf) to 74.87% (fermented tobacco leaf). The materiality is within the range from 41.26 g/m² for non-fermented tobacco leaf up to 41.90 g/m² for fermented tobacco leaf, and the leaf thickness is 91.5 μm (non-fermented tobacco leaf) up to 77.2 μm (fermented tobacco leaf). The obtained data from non-fermented and fermented tobacco, the content of the main rib (%), the thickness of the tobacco leaves (μm), the materiality of the leaves (g/cm 2), are determined according to recognized methods that are being applied in the operation of the accredited laboratory-L04 within the