Assessment of Water Stress in Tobacco Genotypes using factor and Cluster Analyses

Drought is one of the most important factors limiting growth of plants around the world and the most common environmental stress. It is well known that the effect of water stress on growth and yield depends on genotype of the plant. Therefore, the importance of drought stress in tobacco plants is important. The aim of this study was to classify of tobacco genotypes under drought stress by factor analysis and cluster analysis. In this study, 18 genotypes of tobacco were examined using a split plot design based on randomized complete block design (RCBD) with three replications. Levels of water stress treatments were defined as main plot (perfect, 50 and 75 % of available water) and genotypes were considered as sub-plot. The results of factor analysis in control (full or perfect irrigation) determined five factors explained 92.3 of total variation, correspondingly in 50 and 75% of available water, 97.95 and 98.50% of total variations explained by two factors. At the control level, RosecaNela, P.B.D.6 and Comstake Spanish genotypes were introduced as the highest genotypes, and genotypes of drought tolerant genotypes were introduced in the genotypes of VirAurea, Virgina Free and Trumpf genotypes. RXT and NC-60 genotypes, which had low yield, were sensitive to water stress. The cluster analysis using UPGMA method classified the genotypes under control in four groups and under stress conditions in three separate groups. Therefore, there is variation between genotypes under control and stress conditions. Keywords: Cluster Analysis, , Factor Analysis, Tobacco, Water Stress