Abstract
The intragenotypic varlability of a quantitative character can be measured in two ways : (1) variation of mean phenotype to different enviornments and known. as phenotypic plasticity. The latter is generally attributed to developmental instability which is assumed to be due to accidents in the developmental processes of individual plants and unrelated to external environmental conditions. The genetic analysis of the intragenotypic variability for plant height was carried out by mea.ns of complete diallel crosses of six inbred lines in rustica tobacco (Nicotiana rustica L.) under seven conditions. The magnitude of inter-plant variation of plant height was estimated from standard deviation within plot.
