New cultivars for the Italian Burley industry Eugenio Cozzolino, Vincenzo Leone, Pasquale Lombardi Consiglio per la Sperimentazione e la Ricerca in Agricoltura – Centro di Ricerca per le colture alternative al tabacco (CRA-CAT), Italy
Introduction The Burley tobacco produced in the province of Caserta is appreciated for light texture, neutral taste and low alkaloid content. However, lack of information about performance of new cultivars in the area might be cause of neglecting opportunities for further progress of the industry. To provide such information an on-farm variety trial is on course and here we report the results of the first year.
Materials and methods The trial is conducted at Vitulazio (province of Caserta) in a farm of the A LESSIA farming company, testing fourteen lines, including as control the cultivar FB9, widely cultivated in the area, in a complete block design with two replicates in plots of 40 m2. Cultural practices are those customary for the type: fertilization according to the regional guidelines for areas vulnerable to nitrate pollution, drip irrigation, harvesting by three or more primings, curing under plastic barns. The cured leaf was graded by visual assessment on a decimal scale by an expert. An index of value yield (equivalent yield) was obtained multiplying cured yield by the visual score divided by its maximum value. A statistical summary of the results was computed by fitting a general linear model to the responses, using the R environment (R Core Team, 2012) and functions of the contributed packages arm, BiplotGUI (La Grange et al., 2009) e ggplot2 (Wickham, 2009)..
Results PM34
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STARTAR
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737AR
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80
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110
Days to flower
4
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90
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FB3119
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KT200LC
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HB4488P
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F40
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KT206LC F24
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FB82 KT204LC
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FB9
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START
FB3117
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5
6
Cured yield (t/ha)
7
5
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6
7
8
Visual quality (1:10)
3
4
5
Value yield (t/ha)
Figure 1. Earliness, visual quality index, cured and value yield of fourteen lines of Burley tobacco. Means with 68% and 95% confidence intervals.
References Gelman A. and Yu-Sung S. (2013). arm: Data Analysis Using Regression and Multilevel/Hierarchical Models. R package version 1.6-09. http://CRAN.R-project.org/package=arm La Grange et al. 2009. BiplotGUI: Interactive Biplots in R. J. Statistical Software 30:1-37. R Development Core Team, 2013. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0, http://www.R-project.org. Wickham H., 2008. ggplot2: elegant graphics for data analysis. Springer New York, 2009. 2013 CORESTA Joint Study Group Meeting • Agronomy & Leaf integrity / Phytopathology & Genetics • 13-17 October 2013 / Brufa di Torgiano, Italy
Figure 2. Correlation biplot of earliness, visual quality index, cured and value yield of fourteen lines of Burley tobacco. Lines are coloured by earliness and groups are delimited by convex hulls (dotted lines). Axes and line names are projected on the plane of the first two principal components and response values for the lines can be read on the axes by orthogonal projection of the line points on the axes. Cured and value yield are in tonnes per hectare and visual quality in a 1:10 scale.
Three groups of lines were differentiated on account of earliness and yield, with a positive correlation between these traits: late flowering lines (PM34, STARTAR, 737AR, START, FB82) showed yields considerably higher than early flowering (FB3117 e FB3119) and intermediate ones (all the others) (figure 1 and 2). Late flowering, high yielding lines showed large differences for leaf quality, with STARTAR the best and FB82 the worst. Lines of average earliness were more similar for leaf quality, which was quite high, while earliness was associated with low quality. Value yield for the best two lines (STARTAR and PM34) was nearly double compared with the worst two lines (FB3117 and FB3119).
Conclusions Large differences among the tested lines for earliness, cured yield, leaf visual quality and value yield highlight the opportunity for Burley production improvement through cultivar choice. Two lines (STARTAR and PM3) coupled high cured yields (around 6.5 t ha−1) with high visual quality.