ORIGINAL SCIENTIFIC PAPER The contributions to the amelioration of the industrial quality of Virginia type tobacco cultivated on low productive soils Jenica Calina 1, Aurel Calina 1, Pompilica Iagaru 2, Gligor Ciortea 2 1University of Craiova, Faculty of Agriculture, Romania (e-mail: jeni_calina@yahoo.com) 2 Lucian Blaga University of Sibiu, Faculty of Agricultural Sciences, Food Industry and Environmental Protection, Romania Abstract For the program of improving Virginia tobacco of interest there are the lines and soils achieving yellow-orange colour leaves (with a sweet taste), uniform yellow colour, whose dry tobacco production is over 80% Superior + I classes. The industrial quality of tobacco is determined both by the characteristics of green leaves at the moment of harvest and the physical characteristics of the dry leaf. The results of the researches made for the industrial quality of dry tobacco, with a mean of three years, reveal a great variability within the studied biologic material.the analysis of the data reveals that 18 sorts have given good results, with over 80 % of production at Superior + I classes, which can be genetic sources for improving the quality of unfermented tobacco. Key words: tobacco, genotypes, quality, classes. Introduction Under the conditions which are not quite favourable for tobacco culture created in this century, the work wants to identify the sorts with as many as useful features that have to be improved through genetic, sexed recombination, through somatic hybridization and individual selection.the annual amounts of ash of about 2.5 million tones have required the extension of initial surfaces, because, in more than 35 years of existence, more than 110 million tones of waste product ash have been. One hectare of tobacco cultivated ash brings as many incomes as 5.09 ha of wheat, 4.97 ha maize or 6.51 ha sunflower. The quality of tobacco leaves is determined by the industrial, chemical and smoking quality. The final assessment of the optimum quality belongs to smokers. They have to find the pleasant taste, flavour, strength in the smoke of the cigarette (2). The paper purpose was the inventory of genotypes with superior qualitatively attributes, with perspective, which may be used into the tobacco improvement program, suitable for low productive soils. Material and methods The biological material consisted by 29 genotypes specifically: Virginia 207 (Romania); Virginia 196 (Romania); Virginia 180 (Romania) Virginia 177/93 (Romania); Virginia 211 (Romania); Virginia 9028*ASC*Stam C 9 (Romania); Virginia 236 (Romania); Virginia 291 (Romania); Virginia 257 (Romania); Virginia 965 (Romania); Virginia 165 (Romania); Virginia 325 (Romania); Virginia 233 (Roumania); Zemun 1973 *ASC* Virginia 226 (Romania); Virginia 1173 (Romania); Speight G 28 (Germany); Stam C 9 (Germany); Virginia 427 (Poland), Coker 254 (USA); Coker 394 (USA); Coker 326 (USA); Coker 176 (USA); Mc Nair 944 (USA); Virginia 3593 (USA); Virginia 24 (Canada); Virginia 3802 (Canada); Virginia 3370 (Canada); Virginia 3373 (India); Virginia 3350 (India) and was studied in 298
Genetika, oplemenjivanje bilja i sjemenarstvo Işalniţa Experimental Centre within the Faculty of Agronomy in Craiova, for 3 years (2000-2003) under the aspect of qualitative characteristics and under the aspect of adaptability to pedoclimatic, ecologic and culture conditions on the steam power plant ash dumps, for extracting valuable genotypes for improving this species. Işalniţa Experimental Centre has a surface of 4 ha, with a thickness of the deposited ash layer of approximately 15 m, located on the west side of dumps of the left side of Jiu river, next to it, for facilitating water supply. The biological material, 29 domestic and introduced Virginia varieties and lines, was grown in a randomized block design with four replications in the experimental plots were 12 meters long, with two rows on each plot. Was applied the specific technology for Virginia tobacco type adapted to existent conditions from ash, that allow to assure the hereditary potential of each genotype. Thus, the tobacco seedling produced in Malu Mare Experimental Centre, Dolj County was planted between 15-20 May at a distance of 70/35 cm, with a density of 30,000 plants / hectare. Was realized a fertilization with N 100, having in view the good supply of ashes with phosphorus and potassium. The maintenance works consisted in 10 moisten norms of 300 m 3 / hectare. The harvest was done in three stages, dry leafs production being by 6.3 times smaller than those obtained at harvest, because the produces obtained on irrigated ash are more succulent than those from natural soils. Tobacco leaves drying was made with natural air currents, and the assessment of their industrial quality was made according to Romanian Technical Norm 511/1980, for unfermented tobacco on 5 classes of quality, according to the colour, fineness, elasticity and consistency of the leaf. Results and discussion The quality of flue- cured tobacco is the essential matter equally concerning researchers in the entire world, cultivators, industrialists so that the interaction between the genotype x culture techniques x environment conditions could lead to the transformation of potential quality in a real one. The industrial quality of tobacco is established both by green leave characteristics at the moment of harvest, as well as by the physical characteristics of dried leaf. The quality of dry Virginia tobacco type includes 5 classes: Superior - light yellow leafs, light yellow and orange leafs, with evenly colour. Leafs from under-middle, middle and top story, with fine and elastic tissue; 1 st class - yellow leafs, orange and red-orange leafs. Leafs from under-middle, middle and under-top, with fine and elastic tissue; 2 nd class - leafs by all red nuances. Leafs from under-middle, middle, under-top and top, with elastic tissue; 3 rd class - auburn and brown leafs. Leafs from all foliation stories. Any quality of foliar tissue, without being burnt; 4 th class all colours leafs, from all foliation stories. Any quality of foliar tissue, without being burnt. Yellow colour denotes a superior tobacco, rich in soluble carbohydrates, with a high content of xanthophylls and carotene. These tobaccos are sweets at smoking. The cultivars of Virginia tobacco type from Romania have yellow and yellow-orange leafs and high content of carbohydrates. For the colour, was followed the tonality, intensity and uniformity (1). For Virginia tobacco improvement program of interest are the lines and sorts achieving yelloworange colour leaves (with a sweet taste), uniform yellow colour, whose dry tobacco production is over 80% Superior + I-a classes (3, 4). 44. hrvatski i 4. međunarodni simpozij agronoma 299
The research results on the industrial quality of dry tobacco, on an average of three years reveal a great variability within the studied material. According to the average data of industrial quality registered and marked in Table 1, we can notice that the variation limits on classes of quality are: At the superior class from 0.9 % (at Virginia 233 line) to 4.5% at (Virginia 291), experience average being 1.2 %; At 1 st class from 59.6 % (at Virginia 233) to 92.7 % (Virginia 24); At 2 nd class from 3.1% (Coker 326) to 25% (Virginia 9028*ASC* Stam C 9); At 3 rd class from 0.3 % (Virginia 211 to 9.6 % (Virginia 1173); The data analysis reveals that the greatest tobacco production is at the 1 st classes superior + I tobacco, the limitations being included between 96.3 % at Coker 326 sort and 60.5 % at Virginia 233, the experience average being of 70.1 % of production (Fig, 1, 2). The best results are for the genotypes: Coker 326 (96.3 %); Virginia 207 (93.9%) ; Virginia 211 (93.6%); Coker 176 (91.3%); Virginia 965 (91.3%); Coker 394 (90.5%).18 sorts have also displayed good results, with more than 80 % of production at din superior + I classes (Fig. 2). Among them we mention Coker 254 (89 %); Speight G 28 (89.7%); Mc Nair 944 (87.1%); Virginia 236 (88.3%); Virginia 3802 (86.0%). Of the 29 studied genotypes, only one was under the limitation of the witness, Virginia 233 (60.5%). For the improvement process, we have been interested in the genotypes whose production is included in the Superior + I classes, in a percentage of 81-90 % and 91-100 %. Results allow us to appreciate that there are enough genetic sources for improving the quality of unfermented tobacco (3, 4).The improver exigency has to be even greater as we know that this character has a quantitatively genetic determinism, being powerfully influenced by the pedo-climatic conditions and the drying way. Conclusions 1. The greatest tobacco production is in the superior + I classes, the limitations being included between 96.3% at Coker 326 sort and 60.5% at Virginia 233, the experience mean being of 70.1% of production. 2. The best results are from the genotypes: Coker 326 (96.3 %); Virginia 207 (90.9%); Virginia 211 (93.6%); Coker 176 (91.3 %); Virginia 965 (91.3%); Coker 394 (90.5%); 3. Among the gene sources for the industrial quality we mention the genotypes: Coker 254 (89%); Speight G 28 (89.7%); Mc Nair 944 (87.1%); Virginia 236 (88.3%); Virginia 3802 (86.0%). 4. We recommend as valuable genetically sources, for industrial quality improvement the following genotypes: Coker 326, Virginia 207, Virginia 211, Coker 176, Virginia 965, and Coker 394. References 1. Anitia, P., Marinescu P. (1993). The physiology and the biochemistry of tobacco. Technical publishing House, Bucharest. 2. Sasson A. (1988). Biotechnologies challenge and promise. Technical publishing House, Bucharest. 3. *** (1993). The Bulletin Coresta no. 1-3. 4. *** (1991). Catalogue des Nicotianees en colletion a Bergerac. France. 300
Genetika, oplemenjivanje bilja i sjemenarstvo Table 1.Production on classes of quality at the Virginia tobacco type sorts, lines and hybrids 44. hrvatski i 4. međunarodni simpozij agronoma 301
Figure. 1. The weight of superior + I quality in the total production Figure. 2. Character histogram- dry tobacco industrial quality (Superior + I) 302