|Stipanovic, Robert - Bob|
Submitted to: American Phytopathological Society
Publication Type: Abstract Only
Publication Acceptance Date: 6/10/2008
Publication Date: 7/26/2008
Citation: Tashpulatov, J.J., Gulyamova, T.G., Ruzieva, D.M., Kerbalaeva, A.M., Nasmetova, S.M., Khodjibaeva, S.M., Stipanovic, R.D. 2008. Enzymatic response of cotton plants to the pathogen, Verticillium dahliae [abstract]. American Phytopathological Society. p. 179.
Technical Abstract: Pathogen infection initiates a set of local and systemic responses in plants. These responses include local oxidative burst, which may lead to death of infected cells, and changes of cell walls composition in neighbouring tissues, and de novo synthesis of antimicrobial compounds (phytoalexins) and PR-proteins. The enzymatic response of resistant and susceptible cotton varieties to the pathogenic fungus Verticillium dahliae was studied. The enzymatic activity was measured in cell free extracts of roots, stalks and leaves of 30-day-old plants to determine efficiency of intercellular signal distribution after pathogen treatment. Comparative analysis of the distribution of specific enzymatic activities in tissues of resistant and susceptible varieties before and after infection revealed that the primary localization of activity (except chitinase and peroxidase) was in roots of healthy plants. Although qualitative changes of enzymatic activities in resistant and susceptible cotton varieties were similar, there were significant quantitative differences. Specifically, the activity of all of the studied enzymes except amylase was higher in the resistant variety. The highest enzymatic activity in both varieties was located in roots, except peroxidase; the activity of the latter was highest in leaves. The increase of enzymatic activity in response to pathogen action testifies to a defensive reaction in both varieties. Expressed activity in resistant and susceptible plants was highest in roots – the place of direct contact between the plant and pathogen. Thus, the data suggests that the systemic increase of chitinase, peroxidase, glucanase and xylanase activities may be considered part of cotton’s defensive reaction in response to the pathogenic fungus V. dahliae.