Evaluation of genetic variation between some variety and lines of pepper (Capsicum annum) and effects of drought stress on its active ingredient

Analysis of genetic variation is the first step in plant breeding programs. The most important secondary metabolites of capsicum are capsaicin that increasing of this material is favorable for researchers. The aim of this study was Evaluation of genetic variation between some variety and lines of pepper and effects of drought stress on its active ingredient. Irrigation of six native lines of capsicum and the cultivar 0013 were conducted at 25%, 50%, 75% and 100% of field capacity. Morphological traits of fruit were noted and HPLC were used for measurement of fruits capsaicin concentrations. The results of morphological measurements were analyzed by factorial experiment in a completely randomized design with the factors of genotypes at seven levels and stress at four levels (control, 75%, 50% and 25% field capacity). Between capsicum lines in term of the amount of capsaicin there were significant differences but drought stress couldn’t significant effect on them. In Kruskal-Wallis assay based on capsaicin amount, we found that levels of fruits capsicum were different between studied lines at 5 percent levels of probability. The cultivars 2-15 and 6-31 from Biarjomand region khanlhodi village of Shahrood and Abater Gilan had the highest amount of capsaicin in fruits, respectively. Cluster analysis with average method for all entered traits divide lines in 2 groups.