Changes in Peroxidases and Catalase Activity During in vitro Rooting

Enzyme changes in non-rooted (treated with Fe-EDTA) and rooted (treated with Fe-EDDHA) stems of rootstock GF-677 (Prunus amygdalus×P. persica) during adventitious root formation in vitro have been recorded. The first roots appeared approximately after 12 d on the rooting medium. By contrast to non-rooted stems, rooted stems showed a maximum of soluble peroxidase activity on the 9^th day, of ionically bound peroxidase to cell wall on the 6^th and 12^th day and of catalase on the 6^th and the 15^th day. A time course study of changes of soluble peroxidases isoenzymes showed that there was a band visible only in the rooted stems and also a new band appeared three days before the emergence of roots.     

Role of auxin and its modulators in the adventitious rooting of <Emphasis Type="Italic">Eucalyptus</Emphasis> species differing in recalcitrance

It is well established that auxins play a central role in the determination of rooting capacity, which is essential for vegetative propagation. Recent studies with apple trees have pointed to significant effects of auxin stability, wound related phenolics and ethylene production in the control of adventitious rooting. In the present study, a comparative analysis of the adventitious rooting of microcuttings of Eucalyptus saligna (easy-to-root species) and Eucalyptus globulus (difficult-to-root species) was carried out with different types of auxins, light intensities, presence or absence of apical meristem, different concentrations of phenolic compounds and presence or absence of an ethylene action inhibitor. Parameters evaluated were the percent rooting, number of roots per rooted cutting, length of longest root and mean rooting time. Results showed that auxins of intermediate stability are more favorable to rooting (particularly for the recalcitrant species), higher light intensities in the presence of exogenous auxins promote the rooting response, the absence of meristematic apex or externally supplied phenolics are not limiting for the rooting induced by exogenous auxins, and ethylene appears to play a minor role in the development of adventitious roots in microcuttings of Eucalyptus, indicating that the rhizogenic response results from direct effect of auxins.     

Isozymes variability among <Emphasis Type="Italic">Fusarium udum</Emphasis> resistant cultivars of pigeonpea (<Emphasis Type="Italic">Cajanus cajan</Emphasis> (L.) (Millsp)

The present study was carried out to select the different pigeonpea cultivars for resistance against wilt caused by Fusarium udum and to assess the genetic variability among the resistant and susceptible cultivars. These cultivars were screened by root dip inoculation and classified into resistant (ICP 8863 and 9145), moderately resistant (ICP 11681 and Selection-1), susceptible (ICP 7118, TRG-1 and LRG-30) and highly susceptible cultivars (ICP-2376 and LRG-41). The peroxidase activity (PEO) in both leaf and root tissues of four pigeonpea cultivars (ICP 8863, Selection-1, ICP 2376 and LRG-30) were determined at 1^st, 4^th and 7^th day after inoculation (DAI) in healthy and F. udum infected tissues. Higher PEO activity in both leaf and root was observed and at 4^th DAI in susceptible cultivars. In native-PAGE analysis of isozymes, the induction of specific leaf peroxidase band (Em=0.17) and two root peroxidase bands (Em=0.24 and 0.55) were observed in ICP 8863 after inoculation. Significant differences were observed in the leaf phosphatase and esterase banding profiles of all the cultivars. The presence of leaf phosphatase band at Em of 0.04 was observed only in ICP 8863 and 11681. The leaf esterase band (Em=0.3) was well expressed in ICP 8863 when compared to other cultivars. The significance of peroxidase in plant defense mechanism and utility of biochemical markers in breeding programmes are discussed. Part of M.Sc. (Ag) thesis of the first author and approved by the Acharya N.G. Ranga Agricultural University during March 2002.     

Comparative lipid peroxidation,antioxidant defense systems and proline content in roots of two rice cultivars differing in salt tolerance

The changes in the activity of antioxidant enzymes such as superoxide dismutase (SOD: EC 1.15.1.1), catalase (CAT: EC 1.11.1.6), peroxidase (POX: EC 1.11.1.7), ascorbate peroxidase (APOX: EC 1.11.1.11) and glutathione reductase (GR: EC 1.6.4.2), free proline content, and the rate of lipid peroxidation level in terms of malondialdehyde (MDA) in roots of two rice cultivars (cvs.) differing in salt tolerance were investigated. Plants were subjected to three salt treatments, 0, 60, and 120 mol m⁻³ NaCl for 7 days. The results showed that activated oxygen species may play a role in cellular toxicity of NaCl and indicated differences in activation of antioxidant defense systems between the two cvs. The roots of both cultivars showed a decrease in GR activity with increase in salinity. CAT and APOX activities increased with increasing salt stress in roots of salt-tolerant cultivar Pokkali but decreased and showed no change, respectively, in roots of IR-28 cultivar. POX activity decreased with increasing NaCl concentrations in salt-tolerant Pokkali but increased in IR-28. SOD activity showed no change in roots of both cultivars under increasing salinity. MDA level in the roots increased under salt stress in sensitive IR-28 but showed no change in Pokkali. IR-28 produced higher amount of proline under salt stress than in Pokkali. Increasing NaCl concentration caused a reduction in root fresh weight of Pokkali and root dry weight of IR-28. The results indicate that improved tolerance to salt stress in root tissues of rice plants may be accomplished by increased capacity of antioxidative system.     

Biochemical genetic basis of downy mildew resistance in pearl millet

Summary The study of phenolic content and activities of peroxidase and polyphenoloxidase in relation to the degree of downy mildew infection of 12 pearl millet cultivars revealed that these were linearly related to the degree of resistance at both the 30 and 50 day growth stages. Useful electrophoretic differences in peroxidase and polyphenoloxidase were also observed with respect to the expression of resistance.     

Ontogenetic aspects of plant respiration (by the example of <Emphasis Type="Italic">Rubus chamaemorus</Emphasis> L.)

Respiration, content of soluble carbohydrates and phenolics, level of lipid peroxidation, and activity of peroxidase and polyphenoloxidase were investigated in the leaves of cloudberry (Rubus chamaemorus L.) in different stages of shoot development. Age dependence of respiration was wave like with peaks associated with the periods of vegetative growth and fruit bearing. Prior to the onset of fruit bearing, respiration was clearly suppressed, while the content of soluble carbohydrates rose. In the course of development, contribution of cytochrome pathway to total respiration changed more drastically than participation of energy-wise ineffective alternative pathway. Activation of residual (nonmitochondrial) respiration observed in the postgenerative period directly correlated with a rise in activity of polyphenoloxidase and peroxidase in the leaves. The results show that ontogenetic changes in leaf respiration are complex and depend on genetically predetermined processes of plant growth and development. Behavior of respiration and its components predictably reflects changes in the direction and intensity of overall metabolism of plants associated with strict order of alternation of regular age states.     

Effects of lanthanum element on the rooting of loquat plantlet in vitro

We investigated the rooting rate, the number of roots, and the state of growth of loquat (Eriobotrya japonica Lindi) plantlet in medium where La(NO₃)₃ (0.5–100.O μmol/L) was added 20 d after transplanting. The activity of peroxidase, nitrate reductase, and the fresh weight of roots were determined 44 d after transplanting. The result showed that the optimum concentration of La(NO₃)₃ (1.0–3.0 μmol/L) in the rooted medium could increase the rate and the fresh weight of rooting, promote the length of root, and increase the activities of peroxidase and nitrate reductase.     

Soluble sugar,starch and phenolic status during rooting of easy- and difficult-to-root magnolia cultivars

The aim of the study was to determine the effect of indole-3-butyric acid (IBA) and exogenous sucrose concentrations on in vitro rooting, soluble sugar, starch and phenolic production, and ex vitro survival of four magnolia cultivars. There was a significant linear increase in rooting of most magnolia genotypes with an increase in IBA concentration in the medium from 1 to 6 mg L^?1. A further increase of IBA concentration to 10 mg L^?1 decreased (‘Elizabeth’, ‘Burgundy’) or had no effect on rooting frequency (‘Spectrum’). The effect of IBA on rooting of magnolia shoots was modified by sucrose supply. The three out of four magnolia cultivars showed the highest rooting efficiency in the presence of 6 mg L^?1 IBA and 30 g L^?1 of sucrose. Generally, decreasing and increasing the sucrose supply from 30 g L^?1 significantly lowered the rooting frequency. In ‘Yellow Bird’, sucrose at 40 g L^?1 totally blocked root formation. It has been found that the poor rooting ability of ‘Yellow Bird’ coincided with a low soluble sugar content, and high production of starch and phenolics in the shoot bases during the whole rooting period as compared to easy-to-root cultivars. After 5 weeks of the growth on IBA medium, rooted and unrooted shoots were transferred to ex vitro conditions. Both types of shoots showed a high survival and rooting rate (85.4–100%), but they differed in their growth activity and quality. Sucrose concentration in the rooting medium had a post-effect on ex vitro root formation and survival of magnolia plantlets. Ex vitro establishment (13.3%) of recalcitrant ‘Yellow Bird’ was obtained only when the shoots were taken from rooting medium containing the lowest level of sucrose (20 g L^?1).

     

Control of shoot necrosis and plant death during micro-propagation of banana and plantains (<Emphasis Type="Italic">Musa</Emphasis> spp.)

Shoot necrosis and plant death occurred during large-scale propagation of Musa cultivars, viz. Grande Naine (AAA), Dwarf Cavendish (AAA), Nendran (AAB) and Quintal Nendran (AAB). The timing and frequency of necrosis was influenced by the cultivar. Grande Naine and Dwarf Cavendish showed necrosis after the 7^th subculture at frequencies of 27 and 29%, whilst at the rooting stage (after seven transfers of shoot multiplication) the frequencies were 18 and 19% respectively. In Nendran and Quintal Nendran, necrosis occurred after the 5^th subculture at frequencies of 38 and 40%, and at the rooting stage (after five transfers of shoot multiplication) the frequencies of necrosis were 26 and 27% respectively. Several methods were tested for alleviating shoot necrosis, including shortening the culture period, altering the media salt strength, use of various plant growth regulators, different levels of sucrose, fructose, silver nitrate, and increasing the concentration of calcium chloride. Only the addition of calcium chloride proved effective in reducing shoot necrosis. Transfer of shoots showing early signs of necrosis to Murashige and Skoog medium with an addition of 50–100 mg l^-1 calcium chloride facilitated recovery of more than 90% of the shoots. The same addition to shoot multiplication medium for 2–4 transfers after the 6^th and 4^th subcultures respectively, for bananas and plantains alleviated shoot necrosis up to the 12^th subculture in all cultivars. This also prevented necrosis during subsequent rooting. The prevention of loss of cultures by shoot necrosis by the addition of calcium chloride at the shoot multiplication stage, and thereby the reduction of production cost, will be beneficial to the banana micro-propagation industry.     

Dynamics of extractable carbohydrates in Pisum sativum. III. The effect of IAA and temperature on content and translocation of carbohydrates in pea cuttings during rooting

The number of roots formed in cuttings of pea ( Pisum sativum L. cv. Alaska) was regulated both by the temperature and by IAA, whereas the time to the appearance of the first roots was regulated only by the temperature. Cuttings treated with 10^-3 M IAA had a smaller content of extractable carbohydrates than the control ones irrespective of the temperature. In the bases of cuttings rooted at 25°C the content of extractable carbohydrates was lower than in those rooted at 15°C. Cuttings treated with IAA showed up to elevenfold increase of extractable carbohydrates in the bases at day 3. This increase of soluble sugars was not correlated with the number of roots formed or the speed of rooting. It is concluded that IAA affects the accumulation of carbohydrates, and this is not connected with the rooting ability of the cuttings.     

Mechanisms of salt tolerance and interactive effects of <Emphasis Type="Italic">Azospirillum brasilense</Emphasis> inoculation on maize cultivars grown under salt stress conditions

The present work has been performed to study the growth and metabolic activities of two maize cultivars (cv. 323 and cv. 324) which are shown to have different tolerances to salt stress and to determine the effects of inoculation with Azospirillum spp. Along with identifying the mechanisms of maize salt tolerance and the role of Azospirillum (growth promoting rhizobacteria) in elevating salinity stress conditions is examined Maize cv. 323 was the most sensitive to salinity, while cultivar 324 was the most resistant of the 12 maize cultivars tested. Cultivars differences were apparent with certain growth criteria as well as related metabolic activities. The lack of a negative response to increasing NaCl concentration for water content, dry matter yield and leaf area of cv. 324 up to a concentration of – 0.6 MPa indicated salt tolerance. While for cv. 323 there was a marked inhibitory effect of salinity on growth. In the tolerant cv. 324, soluble and total saccharides, soluble protein in shoots and total protein in roots increased with salinity stress. The sensitivity of cv. 323 however was associated with depletion in saccharides and proteins. Proline accumulation was higher and detected earlier at a lower salinity concentration in the salt sensitive cv. 323 comapred to the salt tolerant cv. 324. When salt stressed maize was inoculated with Azospirillum, proline concentration declined significantly. The present study showed, in general, that the concentration of most amino acid increased on exposure to NaCl as well as when inoculated with Azospirillum. The relatively high salt tolerance of cv. 324, compared with cv. 323 was associated with a significantly high K⁺/Na⁺ ratio. Azospirillum inoculation markedly altered the selectivity of Na⁺, K⁺ and Ca⁺⁺ especially in the salt sensitive cultivar cv. 323. Azospirillum restricted Na⁺ uptake and enhanced the uptake of K⁺ and Ca⁺⁺ in cv. 323. A sharp reduction in the activity of nitrate reductase and nitrogenase in shoots and roots of both cultivars was induced by salinity stress. This reduction in NR and NA activity was highly significant at all salinity concentrations. Azospirillum inoculation stimulated NR and nitrogenase activity in both shoots and roots of both cultivars. The differential effect of Azospirillum inoculation on maize cv. 323 and cv. 324 illustrates the different sensitivity of these two cultivars to stress, but still does not provide any clues as to the key events leading to this difference.     

NAA处理对艾纳香扦插生根生理生化特性的影响

为探讨NAA对艾纳香(Blumea balsamifera)扦插生根的影响,4 a生艾纳香健康枝条用500 mg/L NAA处理,对生根过程中的生理生化特征进行了研究.结果表明,艾纳香扦插生根率与内源IAA、GA含量和IAA/ABA呈正相关,而与ABA含量呈负相关.NAA处理能提高插穗的IAA含量,降低ABA含量,有助...     

Anatomical and Biochemical Changes Associated with In Vitro Rhizogenesis in Dendrocalamus giganteus

Successful micropropagation protocol of a difficult-to-root bamboo species, Dendrocalamus giganteus (10–15 years old) along with the analysis of anatomical and biochemical changes during in vitro rhizogenesis was accomplished. Proliferated axillary shoots from nodal segments of 10–15 years old field culms exhibited shoot necrosis during multiple shoot formation phase and was controlled by subculturing in modified MS liquid medium having 825 mg ^l?1 NH₄NO₃, 3800 mg ^l?1 KNO₃, 740 mg ^l?1 MgSO₄ and 9% coconut water, 26.64 μM 6-benzylaminopurine (BA) and 0.46 μM kinetin. These multiple shoots proliferated from field grown culms, failed to root and hence callus was induced on MS solid medium containing 4.44 μM BA, 4.52 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 5.37 μM naphthalene acetic acid (NAA). Organogenesis from the callus was achieved upon transfer to MS medium with 11.10 μM BA and 2.32 pM kinetin. The callus-derived shoots multiplied on modified MS medium were rooted the best (91%) by culturing 3 days on MS medium having glucose (0.5%), sucrose (2.5%) and 98.41 μM indolebutyric acid (IBA) and subsequently to IBA-free MS medium containing 3% sucrose. Studies on peroxidase and IAA oxidase activity and endogenous free- and bound-IAA content showed that IAA oxidase and peroxidase oxidize endogenous IAA resulting in root initials formation. Anatomical studies confirmed the root primordia formation from 3^rd day of IBA treatment and primordia were visible over the surface on 8^th to 10^th day. However, the shoot necrosis symptoms which started on 6^th day of treatment intensified by 10^th day leading to the death of the whole shoot system by 12^th–15^th day. Nevertheless, on the root formation medium with 9.84 μM IBA, new shoot buds were emerged and showed shoot growth in 60% of the rooted cultures, which were successfully acclimatized in shade-house with 100% survival. The present study establishes rooting of callus-derived shoots as the best way for the successful propagation of the difficult-to-root bamboo, D. giganteus when compared to axillary bud proliferated shoots.     

Characterization of the antioxidant system during the vegetative development of pea plants

The antioxidative system was studied during the development of pea plants. The reduced glutathione (GSH) content was higher in shoots than in roots, but a greater redox state of glutathione existed in roots compared with shoots, at least after 7 d of growth. The 3-d-old seedlings showed the highest content of oxidised ascorbate (DHA), which correlated with the ascorbate oxidase (AAO) activity. Also, the roots exhibited higher DHA content than shoots, correlated with their higher AAO activity. The activities of antioxidant enzymes were much higher in shoots than in roots. Ascorbate peroxidase (APX) activity decreased during the progression of growth in both shoots and roots, whereas peroxidase (POX) activity strongly increased in roots, reflecting a correlation between POX activity and the enhancement of growth. Catalase activity from shoots reached values nearly 3 or 4-fold higher than in roots. The monodehydroascorbate reductase (MDHAR) activity was higher in young seedlings than in more mature tissues, and in roots a decrease in MDHAR was noticed at the 11^th day. No dehydroascorbate reductase (DHAR) was detected in roots from the pea plants and DHAR values detected in seedlings and in shoots were much lower than those of MDHAR. In shoots, GR decreased with the progression of growth, whereas in roots an increase was seen on the 9^th and 11^th days. Finally, superoxide dismutase (SOD) activity increased in shoots during the progression of growth, but specific SOD activity was higher in roots than in shoots.     

Catalase, Peroxidase, and Polyphenoloxidase Activities during Rice Leaf Senescence

The activities of catalase, peroxidase, and polyphenoloxidase were studied in attached and detached rice (Oryza sativa L. cv. Ratna) leaves. Catalase activity decreased while peroxidase and polyphenoloxidase activities increased during senescence of both attached and detached rice leaves. Kinetic (5 mum) and benzimidazole (1 mm), which are known to delay the senescence of detached rice leaves, retarded the decrease of catalase activity during detached leaf senescence. On the other hand, these chemicals accelerated the increase of peroxidase and polyphenoloxidase activities over the water control. Total phenolics accumulated in detached and darkened rice leaves, but in attached leaf senescence in light no accumulation of phenolics was observed.     

Phenolic Compounds and the Polyphenoloxidase and Peroxidase Activity in Callus Tissue Culture-Pathogen Combination of Red Raspberry and Didymella applanata (Niessl.) Sacc.

The content of phenolic compounds as well as the activity of polyphenoloxidase and peroxidase in the red raspberry callus tissue after D. applanata infection were investigated. Two red raspberry cultivars: Latham — relatively resistant and M. Promise — susceptible were used. In the M. Promise cultivar the amount of phenols, especially o-diphenols, decreased after infection and stayed more or less on the same level in Latham cultivar. The activity of polyphenoloxidase increased in both of the investigated cultivars, however in the tissue of Latham cultivar this rise was more pronounced than in the M. Promise one. The changes in peroxidase activity after infection were inconsiderable. The relation between the changes observed after infection in the phenolic metabolism and the differentiated susceptibility of callus tissue to D. applanata of the investigated cultivars was discussed. The obtained results explain partially the browning of infected callus tissue of one of the investigated cultivar i.e. M. Promise which had already been observed in the earlier investigations.     

Assigning a Role to the Endogenous Phenolic Compounds on Adventitious Root Formation of Olive Stem Cuttings

The objective of this study was to role the effect of phenolic compounds on the rooting potential of leafy cuttings of the recalcitrant to root olive cultivar ‘Kalamata’ and the easy to root ‘Arbequina’. Subsamples of cuttings were taken for analysis before planting (day 0) in the mist system and during the early phases of rhizogenesis (EPR). ‘Kalamata’ presented higher initial (day 0) total phenols in summer and total o-diphenols in autumn and spring compared to ‘Arbequina’, while ‘Arbequina’ had significantly higher initial total flavonoids and flavanols in autumn. A positive correlation was found between initial total phenols and rooting ability of ‘Arbequina’. In ‘Kalamata’ a positive correlation was established between initial total o-diphenols and rooting percentage while total flavonoids were negatively correlated with rooting. Generally, total phenols, o-diphenols, flavanols and flavonoids did not differ between the two cultivars and their concentration reduced significantly 15 days after planting. Furthermore, ‘Arbequina’ presented higher initial tyrosol, chlorogenic acid, luteolin-7-glucoside, rutin, quercetin and luteolin in summer and autumn compared to ‘Kalamata’. The above phenolics were positively correlated with the rooting of ‘Arbequina’. Significant changes were observed in the concentration of the individual phenolics during the EPR, whereas chlorogenic acid, rutin, quercetin and luteolin concentration increased significantly from day 1 to 5. In conclusion, there is a clear relationship between the phenolic profile and adventitious rooting of the two olive cultivars and in fact chlorogenic acid and rutin can be proposed as olive rooting enhancers.

     

Root Development Enhanced by Using Indole-3-butyric Acid and Naphthalene Acetic Acid and Associated Biochemical Changes of In Vitro Azalea Microshoots

Based on the importance of producing in vitro adventitious roots, this study was carried out to investigate the effects of indole-3-butyric acid (IBA) and naphthalene acetic acid (NAA) at a concentration of 2 mg L^?1 on the formation of adventitious roots of azalea and their impact on biochemical changes and endogenous hormones. The rooting percentage, root number, and root length were increased in the microshoots of both studied cultivars (‘Mingchao’ and ‘Zihudie’) when the growth medium was supplemented with IBA. Additionally, peroxidase, indole acetic acid oxidase, hydrogen peroxide, and soluble protein contents were improved in both cultivars by auxin treatments especially during the first 7 days of the rooting period. However, application of IBA and NAA increased catalase and polyphenol oxidase in both cultivars during the first 14 and 28 days of culture. The increase in endogenous indole acetic acid (IAA) levels was accompanied by low activity of IAAO during most periods of root induction of microshoots in all treatments. Endogenous gibberellic acid levels were increased after 7 days of culture and then increased again after 28 days of culture. In contrast, the levels of endogenous zeatin riboside and isopentenyl adenosine were decreased with auxin treatments in the first period of the rooting process and then increased after 21 and 28 days of culture. The present study demonstrated that IBA at a concentration of 2 mg L^?1 has a strong effect on azalea rooting. Moreover, the efficiency of IBA and NAA effects on biochemical changes during adventitious root induction was investigated, which may provide new horizons of in vitro rooting production and provide valuable information for the micropropagation of Rhododendron plants.     

Biochemical responses of glyphosate resistant and susceptible soybean plants exposed to glyphosate

Glyphosate is a wide spectrum, non-selective, post-emergence herbicide. It acts on the shikimic acid pathway inhibiting 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), thus obstructing the synthesis of tryptophan, phenylalanine, tyrosine and other secondary products, leading to plant death. Transgenic glyphosate-resistant (GR) soybean [Glycine max (L.)] expressing an glyphosate-insensitive EPSPS enzyme has provided new opportunities for weed control in soybean production. The effect of glyphosate application on chlorophyll level, lipid peroxidation, catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GOPX) and superoxide dismutase (SOD) activities, soluble amino acid levels and protein profile, in leaves and roots, was examined in two conventional (non-GR) and two transgenic (GR) soybean. Glyphosate treatment had no significant impact on lipid peroxidation, whilst the chlorophyll content decreased in only one non-GR cultivar. However, there was a significant increase in the levels of soluble amino acid in roots and leaves, more so in non-GR than in GR soybean cultivars. Root CAT activity increased in non-GR cultivars and was not altered in GR cultivars. In leaves, CAT activity was inhibited in one non-GR and one GR cultivar. GOPX activity increased in one GR cultivar and in both non-GR cultivars. Root APX activity increased in one GR cultivar. The soluble protein profiles as assessed by 1-D gel electrophoresis of selected non-GR and GR soybean lines were unaffected by glyphosate treatment. Neither was formation of new isoenzymes of SOD and CAT observed when these lines were treated by glyphosate. The slight oxidative stress generated by glyphosate has no relevance to plant mortality. The potential antioxidant action of soluble amino acids may be responsible for the lack of lipid peroxidation observed. CAT activity in the roots and soluble amino acids in the leaves can be used as indicators of glyphosate resistance.     

Activity and isoforms of peroxidases, lignin and anatomy, during adventitious rooting in cuttings of Ebenus cretica L

Adventitious rooting of Ebenus cretica cuttings was studied in order to examine a) the rooting ability of different genotypes in relation to electrophoretic patterns of peroxidases. b) the activity and electrophoretic patterns of soluble and wall ionically bound peroxidases, the lignin content and anatomical changes in the control and IBA treated cuttings of and genotypes in the course of adventitious root formation. In addition, a fraction of soluble cationic peroxidases was separated by gel filtration chromatography from the total soluble peroxidases of a genotype. No rooting occurred in cuttings without IBA-treatment. In both genotypes, electrophoretic patterns of soluble anionic peroxidases revealed two common peroxidase isoforms, while a fast-migrating anionic peroxidase isoform (A3) appeared only in genotypes. Both genotypes showed similar patterns of soluble, as well as wall ionically bound cationic peroxidase isoforms. The number of isoforms was unchanged during the rooting process (induction, initiation and expression phase) but an increase in peroxidase activity (initiation phase) followed by decrease has been found in IBA-treated cuttings. During initiation phase the lignin content was almost similar to that on day 0 in genotype while it was reduced at by about 50% in genotype at the respective time. Microscopic observations revealed anatomical differences between genotypes. According to this study, the and genotypes display differences in anatomy, lignin content, activity of soluble peroxidases and the electrophoretic patterns of soluble anionic peroxidase isoforms. The A3-anionic peroxidase isoform could be used as biochemical marker to distinguish and genotypes of E. cretica and seems to be correlated to lignin synthesis in rooting process.