Increasing resistance of chrysanthemum to white rust disease : the role of mutant genotypes and enzymes activities

Abstract

Chrysanthemum is an ornamental crop with high economic value and consistently received hight demand attributed to its amazing beautifulness. However, white rust disease has drastically suppressed the growth and production of chrysanthemum. The purpose of this study was to obtain genetic and phenotypic diversity characters of peroxidase (pod), polyphenol oxidase (ppo), phenylalanine ammonia lyase (pal) and their resistant component of enzymes activity. The eksperiment was conducted using a randomized block design. The treatments consisted of 37 mutants and 11 genotypes chrysanthemum parents with two replications. Observations were made for pod, ppo and pal enzyme activities. Results showed pod, ppo, and pal enzyme activities had narrow genetic and phenotypic variabilities. Further, chrysanthemum mutant obtained enzyme activities is better than the best control, namely 18.30.068, 10.10.010, 1.30.038, 20.35.056, 18.20.112, 18.25.079, 9.35.162, 18.20.089 and 16.35.086 genotypes. Pod, ppo and pal enzymes activity are more resistant to higher than the susceptible genotype chrysanthemum white rust disease. The other finding is as revealed by negative correlation between disease intensity character and pod, ppo and pal enzymes activity, while disease incidence and the rate disease development characters did not correlate with the third enzymes activity characters.