Reaction of winter oilseed rape callus to different concentrations of elicitors: pectinase or chitosan

Abstract

The aim of the presented methodical experiments was 1) the evaluation if callus of winter oilseed rape (Brassica napus var. oleifera L.) initiates a defence reaction to fungal elicitors: pectinase (polygalacturonase) or chitosan, and 2) the choice of the elicitor doses, which evoke the strongest tissue reaction. The results obtained will be used in the next experiments relating the studies of pathogenesis mechanisms proceeding in rape plants infected by necrotrophic fungi. The defence response was estimated on the basis of changes in electrolyte leakage from cells, metabolic efficiency, phenolic content and catalase activity. In the experiment pectinase was used at concentration of 3, 8, 16, 133 and 166 ~tl per 1 cm 3 of culture medium while chitosan at: 25, 50, 75 and I00 lag.cm 3. Both elicitors increased cell membrane permeability: pectinase at the doses 3 3 equal orgreater to 16 lal.cm -while chitosan of 25 lag.cm-. The greatest metabolic inefficiency was observed in calli elicited with 16 pl.cm 3 pectinase and with chitosan of 100 lag.cm -3. The decrease in phenolic content was noted under influence of most doses of both elicitors. The highest catalase activity was evoked by pectinase of 8 lal.cm -3 and chitosan of 75 and 100 pg.cm 3. The results indicated that 8-16 lal.cm -3 of pectinase and 100 lag.cm 3 of chitosan caused the strongest defence reaction of oilseed rape tissue. List of abbreviations: B A P -6-benzylaminopurine;CAT -catalase; DW -dry weight; EL -electrolyte leakage; FW -fresh weight; HE -heat emission; MEC -metabolic efficiency coefficient; P -p h e n olics; P A L -phenylalanine ammonia-lyase; R -respiration rate; ROS -reactive oxygen species; 2,4-D -2,4-dichlorophenoxyacetic acid.

Physiological and Biochemical Response to Fusarium culmorum Infection in Three Durum Wheat Genotypes at Seedling and Full Anthesis Stage

“…Their biosynthesis occurs both before and after the infection [ 52 ]. The defensive role of phenolics in fungal infections in plants was confirmed in our previous studies [ 53 , 54 , 55 ]. The phenolic compounds involved in the immune response to pathogen attack include salicylic and chlorogenic acids.…”

Metabolic Effects of Elicitors on the Biosynthesis of Tropane Alkaloids in Medicinal Plants

“…Pectinase is a general term for a category of enzymes that break down pectin. Its main sources are microorganisms, and it has also been studied as an elicitor in some experiments [41,42]. Pitta Alvarez et al found that pectinase increased the hyoscyamine content in Brugmansia candida hairy root cells and promoted the release of both hyoscyamine and scopolamine.…”

Function of the photosynthetic apparatus of oilseed winter rape under elicitation by Phoma lingam phytotoxins in relation to carotenoid and phenolic levels

“…Many of these substances were described as phytoalexins or scavengers of reactive oxygen species. The role of phenolics in plant defence under fungal infection has been confirmed in some studies (Pła_ zek et al 2003(Pła_ zek et al , 2005Pourcel et al 2007). Shadle et al (2003) have been found that tobacco plants with high level of phenylpropanoids markedly reduced the susceptibility to infection with the fungal pathogen Cercospora nicotianae.…”