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The role of hydrogen peroxide in the regulation of glucose-6-phosphate dehydrogenase (G6PDH) activity in the red kidney bean (Phaseolus vulgaris L.) roots under salt stress (100 mM NaCl) was investigated. Salt stress caused the increase of the activities of G6PDH and antioxidative enzymes including ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), as well as H2O2 production. The application of H2O2 (1 mM) also enhanced the activities of G6PDH as well as antioxidative enzymes. In the presence of exogenous CAT, H2O2 content was decreased, and the enhanced activities of G6PDH and antioxidative enzymes induced by NaCl or by exogenous H2O2 were also abolished, suggesting that the enhancement of the above enzyme activities under salt stress was a result of the increased endogenous H2O2 levels. Further results showed that the effects of NaCl and H2O2 on the activities of antioxidative enzymes were diminished by Na3PO4 (a G6PDH inhibitor), suggesting G6PDH activity is required in enhancing the activities of antioxidative enzymes. The enhanced membrane leakage, lipid peroxidation, H2O2 and O2 - contents, G6PDH and antioxidative enzyme activities under salt stress were all recovered to control level when the red kidney bean seedlings treated with 100 mM NaCl for 6 d were transferred to the control conditions for 8 d.

cDNA-AFLP fingerprinting was used to identify genes with modulated expression during germination in common bean (Phaseolus vulgaris L.). The analysis was performed on the embryo axes. Nine time points covering the whole germination were considered and 800 transcript-derived fragments (PvTDFs) were scored. Among them, 80 % showed no changes during germination. The 97 PvTDFs showing differential expressions during germination were sequenced along with 14 constant transcripts that were randomly chosen. The expression of seven variable PvTDFs was confirmed by real-time RT-PCR. We observed that 92 % of the transcript changes, including 35 % of appearing mRNAs, took place before radicule protrusion, 0-17 h after imbibition (HAI). A major shift in gene expression was observed between 9 and 14 HAI, suggesting a key moment of cell re-programming. Sequence homologies were found for 52 % of the sequenced PvTDFs. The identified transcripts encode proteins belonging to several functional groups including transcription factors, proteins involved in storage compound hydrolysis, cell elongation or oxidative stress protection.

Three genetic similarity coefficients were estimated and compared for their usefulness: simple matching (S SM), Jaccard's (S J) and Dice's (S D), all based on dominant markers data from individuals representing predominantly self-pollinating species. AFLP markers were used to analyze 139 Phaseolus vulgaris L. (common bean) and 67 Lactuca saligna L. (least lettuce) accessions, and RAPD markers were used to analyze 110 Triticum dicoccoides Koern. (wild emmer wheat) accessions. Similar discriminating structure and power based on the three genetic similarity coefficients was found for each of the three species. This discriminating power was high for both P. vulgaris and L. saligna but moderate for T. dicoccoides. With closely related individuals, as in our study, the absence of a band in two individuals should be due to an identical cause inherited from the same ancestor. Accordingly we propose the use of S SM, which alone out of the three examined coefficients involved shared absence of DNA bands, as contributing to genetic similarity. When RAPDs are employed, inferences about population structure and nucleotide divergence should be made with prudence as the nature of genetic variation uncovered by RAPDs is often unclear.

It is hypothesized that since protein α-amylase inhibitor (α-AI) and stimulator might be present together in red kidney bean (Phaseolus vulgaris L.) seeds, their in vitro interactions might influence their detection and quantification. Assay of α-AI using extracts from the embryonic axes revealed an unexpected finding in that the extracts stimulated rather than inhibited α-amylase activity. The cotyledon extracts exhibited inhibitory or enhancement effect on α-amylase activity depending on whether prior to the α-amylase assay they had been boiled for 10 min or not. Phytohemagglutinin (PHA-L in particular) is implicated in the present study as a stimulator of α-amylase activity co-extracted with α-AI from red kidney bean cotyledons. The importance of these findings is discussed in relation to the possible widespread occurrence of protein α-amylase stimulator in seeds and other plant parts.

The role of hydrogen peroxide in the regulation of glucose-6-phosphate dehydrogenase (G6PDH) activity in the red kidney bean ( Phaseolus vulgaris L.) roots under salt stress (100 mM NaCl) was investigated. Salt stress caused the increase of the activities of G6PDH and antioxidative enzymes including ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), as well as HO production. The application of HO (1 mM) also enhanced the activities of G6PDH as well as antioxidative enzymes. In the presence of exogenous CAT, HO content was decreased, and the enhanced activities of G6PDH and antioxidative enzymes induced by NaCl or by exogenous HO were also abolished, suggesting that the enhancement of the above enzyme activities under salt stress was a result of the increased endogenous HO levels. Further results showed that the effects of NaCl and HO on the activities of antioxidative enzymes were diminished by NaPO (a G6PDH inhibitor), suggesting G6PDH activity is required in enhancing the activities of antioxidative enzymes. The enhanced membrane leakage, lipid peroxidation, HO and O - contents, G6PDH and antioxidative enzyme activities under salt stress were all recovered to control level when the red kidney bean seedlings treated with 100 mM NaCl for 6 d were transferred to the control conditions for 8 d. [ABSTRACT FROM AUTHOR]

DNA-AFLP fingerprinting was used to identify genes with modulated expression during germination in common bean ( Phaseolus vulgaris L.). The analysis was performed on the embryo axes. Nine time points covering the whole germination were considered and 800 transcript-derived fragments (PvTDFs) were scored. Among them, 80 % showed no changes during germination. The 97 PvTDFs showing differential expressions during germination were sequenced along with 14 constant transcripts that were randomly chosen. The expression of seven variable PvTDFs was confirmed by real-time RT-PCR. We observed that 92 % of the transcript changes, including 35 % of appearing mRNAs, took place before radicule protrusion, 0-17 h after imbibition (HAI). A major shift in gene expression was observed between 9 and 14 HAI, suggesting a key moment of cell re-programming. Sequence homologies were found for 52 % of the sequenced PvTDFs. The identified transcripts encode proteins belonging to several functional groups including transcription factors, proteins involved in storage compound hydrolysis, cell elongation or oxidative stress protection. [ABSTRACT FROM AUTHOR]

Three genetic similarity coefficients were estimated and compared for their usefulness: simple matching ( S), Jaccard’s ( S) and Dice’s ( S), all based on dominant markers data from individuals representing predominantly self-pollinating species. AFLP markers were used to analyze 139 Phaseolus vulgaris L. (common bean) and 67 Lactuca saligna L. (least lettuce) accessions, and RAPD markers were used to analyze 110 Triticum dicoccoides Koern. (wild emmer wheat) accessions. Similar discriminating structure and power based on the three genetic similarity coefficients was found for each of the three species. This discriminating power was high for both P. vulgaris and L. saligna but moderate for T. dicoccoides. With closely related individuals, as in our study, the absence of a band in two individuals should be due to an identical cause inherited from the same ancestor. Accordingly we propose the use of S, which alone out of the three examined coefficients involved shared absence of DNA bands, as contributing to genetic similarity. When RAPDs are employed, inferences about population structure and nucleotide divergence should be made with prudence as the nature of genetic variation uncovered by RAPDs is often unclear. [ABSTRACT FROM AUTHOR]

An efficient regeneration system for Phaseolus vulgaris was developed from mature seeds germinated on Murashige and Skoog (MS) medium supplemented with thidiazuron or N6 -benzylaminopurine (BA) for 6 d. Using cotyledonary nodes, multiple buds were induced on the MS medium supplemented with 5.0 mg dm3 BA with the induction frequency 71.9 % after 4-week culture. The buds were then transferred onto shoot formation medium containing 1.0 mg dm3 BA, 0.1 mg dm3 gibberellic acid and 2.0 mg dm3 silver nitrate. The addition of AgNO3 enhanced the frequency of the shoot formation from 61.3 to 87.6 %. Root induction medium was half-strength MS medium with 0.75 mg dm-3 indolebutyric acid and 0.02 mg dm3 BA. The average root frequency was 84.3 %. The regenerated plantlets with healthy roots grew successfully when transferred to soil. Using this system we obtained over 10 regenerated plantlets from one explant. [ABSTRACT FROM AUTHOR]

The leaf water potential, gas exchange and chlorophyll fluorescence were evaluated in five common bean (Phaseolus vulgaris) genotypes A222, A320, BAT477, Carioca and Ouro Negro subjected to moderate water deficit. At the maximum water deficit (10 d of water withholding), the leaf water potential of genotypes A320 and A222 was higher (-0.35 and -0.50 MPa) when compared to the other genotypes (-0.67 to -0.77 MPa). The stomatal conductance and net photosynthetic rate were significantly reduced in all genotypes due to the water deficit. The greater reduction in stomatal conductance of A320 under drought resulted in high intrinsic water use efficiency. Mild water deficit affected the photochemical apparatus in bean genotypes probably by down-regulation since plants did not show photoinhibition. The photochemical apparatus of A222 and A320 genotypes was more sensitive to drought stress, showing reduced apparent electron transport even after the recovery of plant water status. On the other hand, even after 10 d of water withholding, the maximum efficiency of photosystem 2 was not affected, what suggest efficiency of the photoprotection mechanisms. [ABSTRACT FROM AUTHOR]

With the aim to contribute to elucidation of the role of phytohormones in plant responses to stresses the endogenous contents of abscisic acid (ABA) and cytokinins (CK) were followed in French bean, maize, sugar beet, and tobacco during water stress and subsequent rehydration. The effects of pre-treatments with exogenous ABA or benzyladenine (BA) before imposition of water stress were also evaluated. The content of ABA increased by water stress, and with the exception of bean plants increased content of ABA remained also after rehydration. In all plant species the ABA content was further increased by ABA pre-treatment, but in bean and maize it decreased by BA pre-treatment. The highest total content of CK was observed in bean and the lowest in maize during water stress. In their spectrum, the storage CK were dominant in bean, and inactive CK in tobacco while in sugar beet and maize all groups were present in comparable amounts. In all plant species, the contents of CK increased during water stress and with exception of bean they decreased back after rehydration. ABA pre-treatment further increased contents of CK in water-stressed bean and tobacco. BA pre-treatment increased contents of CK in sugar beet and tobacco after rehydration. [ABSTRACT FROM AUTHOR]

A simple histo-cytochemical method, combining Evans blue staining to assess cell death and in vivo 3,3′-diaminobenzidine uptake for H2O2 localisation, has been used to evaluate O3 damages in leaf tissues of three Phaseolus vulgaris L. cultivars (Cannellino, BLF, Saxa) with different sensitivity to the pollutant. Bean plants were exposed to a single pulse of O3 (150 ± 10 mm3 m−3 × 3 h) and leaves were examined at different time-span after fumigation. Cannellino proved to be the most sensitive, showing chlorotic spots 2 h after fumigation and chlorotic lesions 24 h later. In BLF, necrotic spots appeared 4 h after fumigation and reddish necrotic lesions (bronzing) developed in further 24 h. Saxa remained symptomless up to 10 d of observation, thus appearing tolerant. The early appearance of symptoms in Cannellino correlated with H2O2 accumulation in leaf tissues and consequent extensive cell death, involving both palisade and spongy mesophyll. H2O2 accumulation was observed also in BLF, though to a lesser extent and dead cells were rare at 2 h after fumigation. However, they increased in number 24 h later, forming small groups in the palisade mesophyll. These groups further enlarged in the next 24 h, again involving only palisade mesophyll. In Saxa leaves, H2O2 accumulation was found only in the epidermal cells, though the number of dead cells was very similar to BLF, at least up to 24 h after fumigation. However, in Saxa, dead cells have been always found singly scattered through the palisade mesophyll, or forming very small groups around substomatal cavity, thus remaining invisible at a macroscopic level. [ABSTRACT FROM AUTHOR]

During ageing of bean ( Phaseolus vulgaris L.) cotyledons in plants with modified life span the time-course of four cytokinins, ethylene, and the end products of free radical attack, lipofuscin-like pigments (LFP), were studied. UV irradiation shortened cotyledon life span, while epicotyl decapitation prolonged it. In controls, LFP increased at the senescence onset but at the end of life span it returned to the initial level. Ethylene increased more than 3-fold at the time of abscission. The content of individual cytokinins (zeatin, zeatin riboside, isopentenyl adenine, isopentenyl adenine riboside) varied differently during ageing but they did not decreased in any case under level observed in young cotyledons at the time of abscission. UV irradiation resulted in 14-fold increase in LFP concentration at the end. Ethylene increased 8-fold 2 h after irradiation. Individual cytokinins increased after UV irradiation to a different extent and time-course, nevertheless cotyledon life span was shortened. Decapitation induced LFP decrease. On day 13, LFP abruptly increased and than decreased and stayed lowered until abscission. Ethylene was maximum on day 24, at the time of abscission, it was above 200 % of control. Decapitation produced transient decrease in some cytokinins namely zeatin and isopentenyl adenine riboside. [ABSTRACT FROM AUTHOR]

Effect of pre-treatments of 1 and 5 μM epibrassinolide or homobrassinolide prior to water stress induction on changes in root nodulation and contents of endogenous abscisic acid (ABA) and cytokinin trans-zeatin riboside (ZR), and nitrogenase activity was investigated in the nodulated roots of Phaseolus vulgaris L. cv. Arka Suvidha. Brassinosteroids in the unstressed plants increased root nodulation, ZR content and nitrogenase activity, and also ameliorated their stress-induced decline in the nodulated roots. The ABA contents in the nodules of control or stressed plants were not altered by brassinosteroids treatment. There was an increase in pod yield by brassinosteroids treatment (5 μM) in the irrigated control as well as stressed plants without influencing pod number or pod length. Among the brassinosteroids, epibrassinolide was relatively more effective. [ABSTRACT FROM AUTHOR]

Effect of phosphorus deficiency on photosynthetic and respiratory CO2 exchanges were analysed in primary leaves of 2-week-old bean ( Phaseolus vulgaris L. cv. Golden Saxa) plants under non-photorespiratory (2 % O2) and photorespiratory (21 % O2) conditions. Low P decreased maximum net photosynthetic rate (PNmax) and increased the time necessary to reach it. In the leaves of P-deficient plants the relative decrease of PNmax at 2 % O2 was larger than at 21 % O2. The results suggested the influence of photorespiration in the cellular turnover of phosphates. [ABSTRACT FROM AUTHOR]

Net photosynthetic rate (PN), transpiration rate (E), and stomatal conductance (gs) during water stress and after rehydration were measured in Phaseolus vulgaris, Beta vulgaris, and Zea mays. Immediately before imposition of water stress by cessation of watering, plants were irrigated with water (control), 100 μM abscisic acid (ABA), and/or 10 μM N6-benzyladenine (BA). In all three species, application of ABA decreased gs, E, and PN already 1 h after application. However, during water stress gs, E, and PN in plants pre-treated with ABA remained higher than in plants pre-treated with water. Positive effects of ABA application were observed also after rehydration. In contrast, the effects of pre-treatment with BA were species-specific. While in bean plants BA application ameliorated negative effect of water stress, only very slight effects were observed in maize, and in sugar beet BA even aggravated the effects of water stress. [ABSTRACT FROM AUTHOR]

We have designed and constructed four oligonucleotides corresponding to the most conserved regions of ornithine decarboxylases (ODC; EC 4.1.1.17) of plant origin. These oligonucleotides were used for the amplification of homologous fragments from several plants ( Zea mays, Capsicum annuum, Sorghum bicolor, Phaseolus vulgaris, Carica papaya and Daucus carota). The amplified fragments were cloned and sequenced, revealing high homology to other ODCs. Peptide sequences coded by these fragments were compared by Clustal analyses. These analyses identified the location of the conserved sequences corresponding to the binding sites of substrate and cofactor. Data demonstrated that the plant ODCs fragments lacked intron sequences and were extremely homologous (over 80 %), constituting a compact group separated from other eukaryotic ODCs. [ABSTRACT FROM AUTHOR]

Using water infiltration of the plant and individual shoots with the subsequent intercellular liquid extraction by the pressure chamber, dynamics of the movement 14C-photosynthates from cell to apoplast, and 14C distribution among photosynthetic products in mesophyll cells and apoplast were studied. The relative quantity of 14C-photosynthetes in leaf apoplast depended on growing conditions; drought increased, and nitrate supply decreased it. When the middle leaves absorbed 14CO2, photosynthates moving down in stem phloem appeared in intercellular space, where they were transported up by transpiration stream. 14C-photosynthates entering to the apex and young leaves were utilized a accumulated, and photosynthates transported to the mature leaves were reloaded into the phloem and reexported. Thus, photosynthates circulated through the plant and were redistributed to the plant organs according to their transpiration. In leaf apoplast photosynthetic sucrose was partly hydrolyzed to glucose and fructose. This increased under high nitrogen supply. The result indicate that apoplast sucrose hydrolysis is the basic cause of the reduction of photosynthate flux from leaves when the nitrate concentration in soil increases. [ABSTRACT FROM AUTHOR]

Using bean seedlings, the effects of benzyladenine (BA) on stomatal conductance (gs), transpiration rate (E), and net photosynthetic rate (PN) were examined in order to find out dose and time responses. In bean seedlings, BA appli roots in concentrations of 1, 5, 10, and 20 µM increased gs and PN of leaves already 1 h after application. E was not markedly affected and water use efficiency (WUE) was increased. However, the effects were mostly transient and after 24 h PN only at 1 and 5 µM BA was increased, and other parameters were not affected or even decreased. In sugar beet seedlings, the effects of hydroxybenzyladenosine (HBA) in addition to those of BA on the same parameters were determined. The both cytokinins were applied in 1, 5, 10, and 20 µM concentrations either to roots or sprayed on leaves However, the effects were inconsistent and the positive effect was observed only after 24 h on PN in plants with roots immersed in 5 and 10 µM BA, or 10 µM HBA, and on E in plants sprayed with 5 µM BA or 10 µM HBA. Thus the stimulation of gas exchange by exogenously applied cytokinins is rather exceptional than general. [ABSTRACT FROM AUTHOR]

The possibility of improving the recovery of plant photosynthesis after water stress by cytokinin-induced stimulation of stomatal opening or delay of leaf senescence was tested. The 6-benzylaminopurine (BAP) in concentrations 1 and 10 μM was applied to the substrate (sand + nutrient solution) or sprayed on primary leaves of 14-d-old Phaseolus vulgaris L. plants sufficiently supplied with water or water-stressed for 4 d. The later ones having relative water content decreased to 69 % were fully rehydrated during the following three days. Parameters of photosynthesis and water relations were measured in primary leaves of 7-, 10-, 14-, and 17-d-old plants. Application of 1 μM BAP slightly delayed leaf senescence: in 17-d-old control plants, net photosynthetic rate (PN) and chlorophyll (Chl) content, and when sprayed on leaves also some of Chl a fluorescence kinetic parameters of BAP-treated leaves were slightly higher than those of untreated leaves. Both types of application of 1 μM BAP slightly improved recovery of plants during rehydration after water stress in terms of increased gad, gab and PN, i.e., parameters which were markedly decreased by mild water stress. However, contents of Chl a, Chl b and carotenoids and parameters of Chl a fluorescence kinetic were not markedly affected by mild water stress and after rehydration were not stimulated by 1 μM BAP. 10 μM BAP had mostly negative effects on the parameters measured. [ABSTRACT FROM AUTHOR]

Eight-day-old bean plants, grown in a nutrient solution, were sprayed with 10−5, 10−4, 10−3, and 10−2 M atrazine. The lipid changes in primary and trifoliate leaves were studied 6 d after the herbicide application. The atrazine treatment inhibited the growth of the trifoliate leaves, and decreased photosynthetic and transpiration rates, the stomatal conductance, and the total lipid content. Atrazine treatment increased 16:0 and 18:3 acids and decreased trans-3-hexadecenoic and 18:2 acids in the phospholipids. The herbicide also increased 16:0 and 18:1 acids in glycolipids and decreased 18:3 acid in monogalactosyl diacylglycerols and digalactosyl diacylglycerols. In most cases the marked changes in fatty acid composition of the main lipid classes were observed at 10−4 and 10−3 M atrazine. [ABSTRACT FROM AUTHOR]

French bean (Phaseolus vulgaris L. cv. Contender) plants at five developmental stages (4, 8, 12, 16 and 20 d after sowing) were exposed to one of three treatments: 1 - 25 °C (control), 2 - exposure to chilling at 10 °C only for 2 d prior to sampling, and 3 - long-term exposure to chilling at 10 °C. Short- and long-term chilling decreased plant growth. Higher concentrations of ascorbate and glutathione were found in the chilling-treated plants throughout the different period of growth in comparison with those in the control plants. The activities of superoxide dismutase, ascorbate peroxidase, and glutathione reductase increased in the chilling-treated seedlings while activities of catalase and peroxidase and of β-carotene content decreased in young chilling-treated plants and slightly increased in older ones. [ABSTRACT FROM AUTHOR]

Fourteen days-old bean plants, grown on sand with Knop's nutrient solution were subjected to water stress (three days without irrigation). The stress led to a decrease in almost all lipid classes except phospholipids in the primary leaves. The content of palmitic acid increased, and that of the linolenic acid decreased. An increase of hexadecenoic acid in phospholipids was also observed. Rewatering for 24 h led to the recovery of the stressed plants including that of the photosynthetic apparatus, but the changes in the lipid composition were insignificant. The spraying of the plants before and after the water stress with 5 × 10-6 M solution of the phenylurea cytokinin 4-PU-30 alleviated negative effect of water stress on the lipid membrane composition permitting the plants to resist the harmful environment. [ABSTRACT FROM AUTHOR]

The decrease in inorganic phosphate concentration in bean (Phaseolus vulgaris L. cv. Złota Saxa) roots induced decrease in respiration rate. The decrease observed in ATP pool in phosphate deficient (-P) roots was greater than it would result from the decline in respiration and possible involvement of alternative pathway, suggesting an increased energy utilization for growth and ion uptake. Indeed, relative growth rate was higher in -P plants until 12 d of culture and later dropped to the rate similar to the control. Net nitrate uptake rate was higher in -P plants than in +P plants at the beginning of phosphate starvation, then during the prolonged culture it decreased rapidly in -P plants and after 19 d it was 8 times lower than that in the control. The decline in ATP production during prolonged phosphate starvation influenced NO3 - uptake more than root growth. [ABSTRACT FROM AUTHOR]

In non-acclimated bean plants heat shock induced oxidative damage (increase of free radical concentration and drop of bound thiols, indicating aggregation of proteins) which was regulated by the enhanced activities of peroxidase and superoxide dismutase, as well as by the accumulation of polyphenols and especially of polyamines. In the plants acclimated to high temperature no oxidative damage occurred following heat shock. [ABSTRACT FROM AUTHOR]

We obtained transformed bean shoots by electroporation of intact bean cells with the plasmid pDPG165 containing bar gene conferring herbicide resistance to plants. Transformed shoots were selected from electroporated callus on herbicide containing media. Data of molecular analysis (PCR and Southern blotting) confirmed the insertion of bar gene in the genome of herbicide resistant shoots. Detailed procedures for obtaining regenerative bean callus, optimization of electroporation of intact cells and transgenic shoots are given. [ABSTRACT FROM AUTHOR]

Effects of water stress at different stages of plant growth on leaf relative water content (RWC), osmotic potential (Ψos) and changes in contents of chlorophyll, abscisic acid (ABA), zeatin riboside (t-ZR), ethylene and proline in six cultivars of French bean (Phaseolus vulgaris L.) were studied. Under water stress, Ψos and RWC were highest in cv. Contender and lowest in cvs. IIHR-909 and Sel-2. The increase in contents of ABA and proline was marked in cv. Contender followed by cv. UPF-626. Decrease in t-ZR and chlorophyll contents was prominent in cv. IIHR-909. Ethylene production surged in all the cultivars under 4- and 8-d stress and declined under 12-d stress. [ABSTRACT FROM AUTHOR]

It is hypothesized that since protein α-amylase inhibitor (α-AI) and stimulator might be present together in red kidney bean (Phaseolus vulgaris L.) seeds, their in vitro interactions might influence their detection and quantification. Assay of α-AI using extracts from the embryonic axes revealed an unexpected finding in that the extracts stimulated rather than inhibited α-amylase activity. The cotyledon extracts exhibited inhibitory or enhancement effect on α-amylase activity depending on whether prior to the α-amylase assay they had been boiled for 10 min or not. Phytohemagglutinin (PHA-L in particular) is implicated in the present study as a stimulator of α-amylase activity co-extracted with α-AI from red kidney bean cotyledons. The importance of these findings is discussed in relation to the possible widespread occurrence of protein α-amylase stimulator in seeds and other plant parts. [ABSTRACT FROM AUTHOR]

Auxins were analysed in roots, stems with apical shoots, and leaves of beans ( Phaseolus vulgaris L. cv. Zorin) cultured for three weeks on media supplied with different concentrations of jasmonic acid (JA). Morphology changes induced by applied JA were reflected in tissue-specific changes of auxins. [ABSTRACT FROM AUTHOR]

Effects of NaCl (150 mM), proline (10 mM) and their combination on growth and contents of chlorophyll, proline and protein of bean ( Phaseolus vulgaris cv. Kizilhaç) seedlings in vitro were investigated. NaCl decreased seedling growth. Proline added to control seedlings did not change seedling growth but decreased chlorophyll and increased protein contents. When proline added to NaCl-treated seedlings growth was increased in comparison with NaCl-treated only. Thus, proline alleviated salinity stress in bean seedlings. [ABSTRACT FROM AUTHOR]

In this work, the effects of NaCl (0, 50, 100, and 150 mM), proline (0, 5 and 10 mM) and NaCl + proline in combinations on activity of polyphenol oxidase (PPO; E.C. 1.10.3.1) and soluble protein content have been investigated in the root, stem and leaf tissues of bean ( Phaseolus vulgaris L.) seedlings grown in embryo culture. PPO activities were higher in all the tissues treated with NaCl, proline and NaCl + proline combinations those that of the control tissues. The protein content was very high in tissues exposed to proline and NaCl + proline combination, but NaCl alone decreased protein contents in root and leaf tissues. The results suggest that proline may play a role as an enzyme-stabilizing agent in salt stress. [ABSTRACT FROM AUTHOR]