biologia plantarum

International journal on Plant Life established by Bohumil Němec in 1959

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Results 2161 to 2190 of 6170:

The Decrease of Extracted Apoplast Protein in Soybean Root Tip by Aluminium Treatment

T. Kataoka, J. Furukawa, T.M. Nakanishi

Biologia plantarum 46:445-449, 2003 | DOI: 10.1023/A:1024302924984

Aluminium effect on the mobility of apoplast protein in root tips was studied. Two-day seedlings of soybean (Glycine max. (L.) Merr. cv. Tsurunoko) were treated with 50 μM AlCl3 for 2 h. Using infiltration method, the apoplast protein in root tips was extracted with 20 or 100 mM MgCl2. When 20 mM MgCl2 was used to collect weakly bound protein to apoplast, the amount of protein extracted was reduced to be about 20 % compared with that of control and the band of 97 kDa disappeared in SDS-PAGE gel. However, the 97 kDa protein could be extracted by 100 mM MgCl2, which were used for extraction of more tightly bound protein to apoplast, and the amount was estimated to be the same as that of control. When the protein was further developed in two-dimensional electrophoresis, three spots were found between pI 6.4 and 6.5. This is the first report of an Al effect on the mobility of apoplast protein.

Thidiazuron Induced Multiple Shoot Induction and Plant Regeneration from Cotyledonary Explants of Mulberry

T. Dennis Thomas

Biologia plantarum 46:529-533, 2003 | DOI: 10.1023/A:1024807426591

A rapid micropropagation protocol through induced multiple shoots from the cotyledonary explant of mulberry (Morus alba L) is described. The highest number of shoots (20.3) was obtained when explants from 14-d-old embryos were cultured on Murashige and Skoog (MS) medium supplemented with 7 μM thidiazuron for 45 d. Of the three cultivars used, cv. S-36 was the best followed by cv. K-2 and S-1. The shoots were transferred to MS medium supplemented with 5 μM 6-benzylaminopurine for elongation. The elongated shoots were rooted on half strength MS medium containing 1 - 7 μM indole 3-butyric acid or 1-naphthalene acetic acid. The rooted plants were transplanted to soil with 90 % success. The emerged shoot primordia probably initiated from the pre-existing meristems since the shoot bud show definite vascular connection to the major vascular tissue.

Alleviation of Ultraviolet-B Radiation-Induced Growth Inhibition of Green Gram by Triadimefon

K. Rajendiran, M.P. Ramanujam

Biologia plantarum 46:621-624, 2003 | DOI: 10.1023/A:1024840301092

Supplementary UV-B (12.2 kJ m-2 d-1 UV-BBE) provided to Vigna radiata for 2 h d-1 suppressed the length of root, shoot and whole plants, number of leaves, total leaf area, leaf area index, specific leaf mass, fresh and dry mass of leaves and shoot, relative growth rate and net productivity. In unstressed green gram plants (10 kJ m-2 d-1 UV-BBE), triadimefon (TRIAD) (20 mg dm-3) enhanced growth in all parameters over control. The growth promoting effect of TRIAD enabled the UV-B impacted plants to overcome the growth inhibitions to varying degrees indicating its protective potential against UV-B stress.

Free Amino Acid, Protein and Water Content Changes Associated with Seed Development in Araucaria angustifolia

L.V. Astarita, E.I.S. Floh, W. Handro

Biologia plantarum 46:53-59, 2003 | DOI: 10.1023/A:1027376730521

The free amino acid, protein, water and dry matter contents were determined during the seed development of Araucaria angustifolia. Soluble and insoluble proteins in the mature seed represent 4.2 % of the fresh matter. The embryonic axis stored the greatest amount of soluble proteins, while cotyledons both with the embryonic axis showed the largest quantities of insoluble proteins in the mature seed. The greatest concentration of free amino acids was detected during the stage when cotyledons start to develop. Glutamic acid, aspartic acid, alanine and serine were predominant in the whole seed while arginine, lysine and γ-aminobutyric acid were present in great amounts only in cotyledons and embryonic axis. Although megagametophyte was important as a source of free amino acids, it was not the major protein storage organ in the mature seed. In the embryogenetic process, the rise of cotyledons is closely related to physiological and biochemical changes.

Effect of 6-benzyladenine and Casein Hydrolysate on Micropropagation of Amorpha fruticosa

H.H. Gao, W. Li, J. Yang, Y. Wang, G.Q. Guo, G.C. Zheng

Biologia plantarum 46:145-148, 2003 | DOI: 10.1023/A:1027361721860

Using apical and axillary nodes as explants, a rapid and efficient method for propagation of Amorpha fruticosa L. has been developed. When grown on Murashige and Skoog (MS) medium supplemented with 8 mg dm-3 benzyladenine, 100 % explants responded with 4.94 shoots per explant after 6-weeks culture, and explants taken from the in vitro proliferated shoots subsequently produced multiple shoots when cultured on the same medium. The addition of casein hydrolysate (200 mg dm-3) enhanced the number of shoots up to 8.77 per subculture, and coconut milk was found to promote the shoot elongation and make them grow more vigorously, 82.53 % excised shoots were rooted on half-strength MS medium containing 2.0 mg dm-3 indoleacetic acid after 3 weeks of incubation. After acclimatization, all of the rooted plantlets established in soil, exhibiting uniform morphological and growth characteristics.

Functioning of the γ-Aminobutyrate Pathway in Wheat Seedlings Affected by Osmotic Stress

I. Bartyzel, K. Pelczar, A. Paszkowski

Biologia plantarum 46:221-225, 2003 | DOI: 10.1023/B:BIOP.0000022255.01125.99

γ-Aminobutyrate (GABA) was the only amino acid out of three amino acid intermediates of GABA shunt that increased significantly after 28 h from the beginning of osmotic stress induced by 20 % polyethylene glycol 6000 in wheat seedlings. At the same time specific activities of glutamate decarboxylase (GAD) and GABA aminotransferase (GABA-T) two enzymes of GABA pathway did not change as compared with the control plants. The response of two GABA-T activities (with pyruvate or 2-oxoglutarate as amino acid acceptor) to aminooxyacetate, 3-chloro-L-alanine and p-hydroxymercuribenzoate prompted us to suggest that at least two isoforms of GABA-T showing different substrate specificity do exist in wheat leaves.

Glutamine Synthetase Activity, Relative Water Content and Water Potential in Maize Submitted to Drought

L.O. Medici, A.T. Machado, R.A. Azevedo, C. Pimentel

Biologia plantarum 46:301-304, 2003 | DOI: 10.1023/B:BIOP.0000022271.35778.17

Two maize (Zea mays L.) hybrids, BR 201 and P 6875, were submitted to drought by withholding irrigation at the vegetative or reproductive phases. During water deficit, in both phases, the relative water content (RWC) was higher and leaf water potential (Ψw) was lower in the hybrid P 6875 than in the hybrid BR201. This response indicated a better osmotic adjustment capacity of the hybrid P 6875 when compared to BR 201. Glutamine synthetase activity was not affected by drought even at a RWC of 60 % and Ψw of -1.2 MPa or during rehydration.

Ecophysiological Characterization of Dormancy States in Turions of the Aquatic Carnivorous Plant Aldrovanda vesiculosa

L. Adamec

Biologia plantarum 46:395-402, 2003 | DOI: 10.1023/B:BIOP.0000023883.62127.5e

Two main dormancy states, innate and imposed dormancy, were characterized in turions (winter buds) of the aquatic carnivorous plant Aldrovanda vesiculosa L. (Droseraceae) kept at 3 ± 1 °C in a refrigerator over the winter. As a result of the breaking of imposed dormancy by a temperature increase (at 15 - 20 °C), some of the turions rose to the water surface within 1 - 3 d and germinated. Turion leaves contained large lacunae with a slimy reticulum and were filled by water over winter. As a result of breaking imposed dormancy, the proportion of gas volume in inner turion leaves rose from 10 - 20 % to 100 % of leaf lacunae volume. The aerobic dark respiration rate of the turions [0.74 - 1.5 μmol O2) kg-1(FM) s-1] slightly increased during innate dormancy after 1 - 2 d at 20 °C, while it was almost constant during the breaking of imposed dormancy. The anaerobic fermentation rate of the turions was only 1.5 - 7 % of the oxygen respiration rate and also was constant during the breaking of imposed dormancy. In turions, the content of glucose, fructose, and sucrose was the same for the two states of dormancy, but starch content was greatly reduced for the imposed dormancy (10 - 11 vs. 32 % DM). It may be suggested that a temperature increase causes an increase of fermentation or respiration which is responsible for the evolution of gas in turion lacunae and, thus, for turion rising.

Allelopathic Potential of Pueraria thunbergiana

H. Kato-Noguchi

Biologia plantarum 46:471-473, 2003 | DOI: 10.1023/B:BIOP.0000023899.52362.f3

The allelopathic potential of Pueraria thunbergiana was investigated under laboratory conditions. The powder of freeze-dried leaves of P. thunbergiana inhibited the germination and the growth of roots and shoots of cress, lettuce, timothy and ryegrass. Significant reductions in the germination and growth of roots and shoots were observed as the powder concentration increased in all bioassays. The putative compounds causing the inhibitory effect of the powder were isolated and determined by their spectral data as cis.trans- and trans,trans-xanthoxin

Physiological Effects of Plant Hormones in Cotton Under Drought

D.M. Pandey, C.L. Goswami, B. Kumar

Biologia plantarum 46:535-540, 2003 | DOI: 10.1023/B:BIOP.0000041058.65442.41

Effects of plant hormones indole-3-yl-acetic acid (IAA), gibberellic acid (GA), benzylaminopurine (BAP), abscisic acid (ABA) and ethrel (ETH) in 5 μM concentration on gas exchange, ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO, EC 4.1.1.39) activity, pigment content and yield in cotton (Gossypium hirsutum L. cv. H-777) under drought were studied. At reproductive stage (55 - 60 d after sowing) these hormones were sprayed on shoots one day prior to stress imposition by withholding irrigation. The soil moisture of control plants was kept at field capacity. Net photosynthetic rate (PN), stomatal conductance (gs), transpiration rate (E), carboxylation efficiency (CE), water use efficiency (WUE), RuBPCO activity, boll number per plant, seed number per plant and lint mass per plant significantly decreased at drought while chlorophyll (Chl) b content and flower number per plant increased. ABA and ETH significantly reduced gas exchange parameters, Chl a and Chl b content. Detrimental drought effect on PN, gs, E, CE, RuBPCO and lint mass per plant was significantly alleviated by BAP and also its effect on seed number and lint mass per plant was significantly alleviated with the ABA treatment.

Molecular Cloning of ADP-Glucose Pyrophosphorylase Large Subunit cDNA from Oncidium

C.R. Li, X.B. Zhang, C.S. Hew

Biologia plantarum 46:613-615, 2003 | DOI: 10.1023/B:BIOP.0000041073.13794.0c

A full-length cDNA for ADP-glucose pyrophosphorylase large subunit (AGPL) was isolated from tropical epiphytic orchid Oncidium hybrid Goldiana. The cDNA was 1754 bp in length with an open reading frame of 1551 bp encoding 517 amino acids. The deduced amino acid sequence showed 73 % identity with those of potato isoform 3 (AGPL3) and Arabidopsis thaliana isoform 1 (AGPL1), 71 % identity with that of barley isoform BLPL. RT-PCR analysis showed that AGPL was expressed in mature leaf, immature leaf, developing inflorescence and flower of Oncidium. No expression was detected in roots.

Responses of Rice Cultivars to the Elevated CO2

D.C. Uprety, N. Dwivedi, V. Jain, R. Mohan, D.C. Saxena, M. Jolly, G. Paswan

Biologia plantarum 46:35-39, 2003 | DOI: 10.1023/A:1022349814670

The effect of CO2 concentration elevated to 575 - 620 µmol mol-1 on growth, tillering, grain yield, net photosynthetic rate, dark respiration rate, stomatal conductance, sugar content and protein profile of two rice (Oryza sativa L.) cultivars Pusa Basmati-1 and Pusa-677 at flowering stage was studied using open top chambers. The cultivar Pusa Basmati-1 responded more markedly for most of the growth and physiological parameters compared to Pusa-677. The increase in grain yield in Pusa Basmati-1 attributed largely to increased grain number. The increased net photosynthetic rate and greater accumulation of sugar contributed significantly to the accelerated development of leaves and tillers in both the cultivars. The reduction in the low molecular mass proteins including Rubisco and increase in high molecular mass photosystem 2 proteins was observed in both the cultivars. Additional sugars may possibly help in balancing the profile of photosynthetic proteins and sustain greater growth and productivity in rice cultivars.

Emergence, Growth and Nutrient Composition of Sugarcane Sprouts Under NaCl Salinity

S. Akhtar, A. Wahid, E. Rasul

Biologia plantarum 46:113-116, 2003 | DOI: 10.1023/A:1022326604192

The changes induced by 80 and 120 mM NaCl during emergence and growth of sprouts in salt-tolerant (CPF-213) and sensitive (L-116) genotypes of sugarcane were determined. The rate and percentage of emergence of sprouts, length and dry mass of shoot and root, and number of nodal roots decreased under salinity. Concentrations of Na and Cl increased and those of K, Ca, N and P decreased with a rise in substrate salinity. A greater salinity tolerance ability of CPF-213 than L-116 was attributable to greater root mass and higher nutrient concentrations in the sprouts of the former genotype.

Micropropagation of Crataeva nurvala

N. Walia, S. Sinha, S.B. Babbar

Biologia plantarum 46:181-185, 2003 | DOI: 10.1023/A:1022882006682

A simple protocol for mass multiplication of Crataeva nurvala, a medicinal tree, from seedling-derived explants is described. Six different types of explants (cotyledonary nodes, epicotyl nodes, hypocotyl segments, first pair of leaves, cotyledons, and root segments) developed shoots on Murashige and Skoog's (MS) basal medium or the same supplemented with different concentrations of 6-benzylaminopurine (BAP). Among the explants tested for caulogenic potential, only the epicotyl and cotyledonary nodal explants developed shoots on MS basal medium, while on BAP (0 - 2.0 mg dm-3) adjuvated media all the explants exhibited caulogenesis. The optimum concentration of BAP varied for these explants. The shoots could be rooted on half strength MS with 0.02 mg dm-3 α-naphthalene acetic acid to get plants, which have been transferred to soil. The explants from in vitro regenerated shoots also possessed a similar caulogenic potential.

The Relationship between Salinity and Cadmium Stress in Barley

I. Smýkalová, B. Zámečníková

Biologia plantarum 46:269-273, 2003 | DOI: 10.1023/A:1022815013951

Distribution of cadmium between roots and shoots of barley was manipulated by the cadmium concentration (0.01 and 0.005 mM Cd2+), pH (4.6 and 5.9) as well as treatment duration. The prolongation of treatment increased dry mass and content of cadmium in plants. The cadmium is accumulated mainly in roots. Presence of both, 0.005 mM Cd2+ and 100 mM NaCl in medium at pH 5.9 (Cd-NaCl plants) resulted in the most severe growth inhibition of plants, but about one half accumulation of cadmium in roots then in a case of only Cd-treated plants. In the Cd-NaCl plants, the net photosynthetic and transpiration rates were less reduced then in a case of only NaCl-treated plants. The treatments also influenced uptake of Ca, Cd, Cu, K, Mg, Na and Zn predominantly in roots.

Propagation of Angelica archangelica Plants in an Air-Sparged Bioreactor from a Novel Embryogenic Cell Line, and their Production of Coumarins

M. Eeva, T. Ojala, P. Tammela, B. Galambosi, H. Vuorela, R. Hiltunen, K. Fagerstedt, P. Vuorela

Biologia plantarum 46:343-347, 2003 | DOI: 10.1023/A:1024309731828

A spontaneously embryogenic cell line of the coumarin producing angelica [Angelica archangelica (L.) subsp. archangelica] was established via callus formation from seedlings grown from sterilized seeds on semi-solid, hormone-free modified B5 medium. The cell line has retained its embryogenic capacity for 5 years. The highest coumarin production for the cell line after 3 weeks of cultivation was achieved in the medium containing 3.0 % sucrose. Jasmonic acid had no statistically significant effect on the biomass or coumarin production. The established embryogenic cell line could be stored using cryopreservation. Plantlets grown in an air-sparged bioreactor were transferred directly to soil and vermiculite, and 63 % of them grew to maturity through two growth seasons. The coumarin content in the regenerated plants was comparable to that in wild plants. Thus this cell line could be used for in vitro propagation.

Nitrogen and Carbon Concentrations, and Stable Isotope Ratios in Mediterranean Shrubs Growing in the Proximity of a CO2 spring

R. Tognetti, J. Peñuelas

Biologia plantarum 46:411-418, 2003 | DOI: 10.1023/A:1024342606329

Seasonal changes in foliage nitrogen (N) and carbon (C) concentrations and δ15N and δ13C ratios were monitored during a year in Erica arborea, Myrtus communis and Juniperus communis co-occurring at a natural CO2 spring (elevated [CO2], about 700 μmol mol-1) and at a nearby control site (ambient [CO2], 360 μmol mol-1) in a Mediterranean environment. Leaf N concentration was lower in elevated [CO2] than in ambient [CO2] for M. communis, higher for J. communis, and dependent on the season for E. arborea. Leaf C concentration was negatively affected by atmospheric CO2 enrichment, regardless of the species. C/N ratio varied concomitantly to N. Leaves in elevated [CO2] showed lower δ13C, and therefore likely lower water use efficiencies than leaves at the control site, regardless of the species, suggesting substantial photosynthetic acclimation under long-term CO2-enriched atmosphere. Leaves of E. arborea showed lower values of δ15N under elevated [CO2], but this was not the case of M. communis and J. communis foliage. The use of the resources and leaf chemical composition are affected by elevated [CO2], but such an effect varies during the year, and is species-dependent. The seasonal dependency and species specificity suggest that plants are able to exploit different available water and N resources within Mediterranean sites.

Spatio-Temporal Variations in Starch Accumulation During Germination and Post-Germinative Growth of Zygotic and Somatic Embryos of Pinus pinaster

M.-N. Jordy, J.-M. Favre

Biologia plantarum 46:507-512, 2003 | DOI: 10.1023/A:1024847007935

During germination and post-germinative growth of Pinus pinaster Ait. seeds, triglycerides are hydrolysed and concurrently the embryo accumulates starch. In this study, the spatio-temporal variation of starch accumulation was described in zygotic embryos associated (ZE+) or not (ZE-) to their megagametophyte and in somatic embryos (SE). In germinating ZE+, starch was accumulated in the growing tissues, following closely the spatio-temporal pattern of triglycerides depletion. In contrast, in ZE- and SE, starch was only found in cortical cells close to the culture medium. In germinating ZE+, the spatio-temporal variations of starch accumulation can be thus interpreted as the result of the changing contact between the megagametophyte and the growing tissues and also of the existing interactions between triglyceride hydrolysis and the allocation of sucrose exported from the megagametophyte.

Image Analysis - Tool for Quantification of Histochemical Detections of Phenolic Compounds, Lignin and Peroxidases in Needles of Norway Spruce

J. Soukupová, J. Albrechtová

Biologia plantarum 46:595-601, 2003 | DOI: 10.1023/A:1024880015204

Image analysis has become a powerful tool for the quantification of histochemical detections mainly in animal and medical sciences. There is not, however, much information about the accuracy of image analysis quantification of histochemical products and their comparison to biochemical analyses. Our study focused on the quantification of histochemically detected amounts of phenolic compounds, lignin and activity of peroxidases in the two youngest age classes of Norway spruce (Picea abies (L.) Karst) needles with the use of image analysis and its comparison with biochemical assays. The image analysis-determined amount of lignin and peroxidase activity was well correlated with its biochemical assay. On the other hand, no optical parameters of the reaction product of the histochemical reaction of phenolics correlated with the biochemical quantification. This proves that results of quantification of histochemical detection with image analysis greatly depend on the character and procedure of the histochemical proof. If it is done in full respect of the conditions of a histochemical reaction it can gain reliable and interesting results. Great advantage of the image analysis approach is quantification of the studied substance in different tissues within single sample as well as among different samples, which in many cases cannot be detected with biochemical tools.

Optimisation of Protoplast Production in White Lupin

A. Sinha, A.C. Wetten, P.D.S. Caligari

Biologia plantarum 46:21-25, 2003 | DOI: 10.1023/A:1027316511865

The influence, was investigated, of abiotic parameters on the isolation of protoplasts from in vitro seedling cotyledons of white lupin. The protoplasts were found to be competent in withstanding a wide range of osmotic potentials of the enzyme medium, however, -2.25 MPa (0.5 M mannitol), resulted in the highest yield of protoplasts. The pH of the isolation medium also had a profound effect on protoplast production. Vacuum infiltration of the enzyme solution into the cotyledon tissue resulted in a progressive drop in the yield of protoplasts. The speed and duration of orbital agitation of the cotyledon tissue played a significant role in the release of protoplasts and a two step (stationary-gyratory) regime was found to be better than the gyratory-only system.

Heat Shock Proteins in the Terrestrial Epilithic Cyanobacterium Tolypothrix byssoidea

S.P. Adhikary

Biologia plantarum 46:125-128, 2003 | DOI: 10.1023/A:1027301503204

The cyanobacterial crust occurring in desiccated state exposed to high temperature and solar radiation on the rock surface contained several low molecular mass (LMM) proteins (10.5, 13, and 25 kDa), water stress protein (wsp, 39 kDa), additional proteins (43 and 49 kDa), a chaperonin (58 kDa), and a stress-induced protein (84 kDa). When the crust was exposed to UV-C radiation, it counteracted the UV-B damage by overproduction of certain proteins and synthesis of two high molecular mass (HMM) proteins. Exposure of the crust to heat had an adverse effect on the survival of the organism there-in which was due to repression of few proteins. Unlike the modification pattern of protein synthesis in the cyanobacterium inhabiting the crust, the same organism grown in culture could tolerate heat by synthesizing two HMM proteins. Several proteins of diverse groups were repressed in the cyanobacterium in culture upon exposure to UV-C, which was counteracted by induction of three new polypeptides (chaperonin and HMMs), and overproduction of one 41 kDa protein.

Glutamate Oxaloacetic Transaminase and Malate Dehydrogenase Isozymes of Zea mays L. × Tripsacum dactyloides L. Hybrids and Parents

V. Tsanev, R. Vladova, K. Petkolicheva, B. Kraptchev, C. Milanov

Biologia plantarum 46:189-194, 2003 | DOI: 10.1023/B:BIOP.0000022250.16372.0f

Electrophoretic patterns of glutamate oxaloacetic transaminase (Got) and malate dehydrogenase (Mdh) of Zea mays L. × Tripsacum dactyloides L. hybrids and their parents have been compared. The results suggested that Got and Mdh isozymes may be used as markers for genic regions on 5 S and 6 L maize chromosomes and for linkage groups D and L on T. dactyloides chromosomes, syntenic to genic regions on 5 S and 6 L maize chromosomes. The latter have a regulatory effect on fertility and on the apomictic mode of reproduction.

Transgenic Rice Plants Expressing Bacillus subtilis Protoporphyrinogen Oxidase Gene Show Low Herbicide Oxyfluorfen Resistance

S.B. Ha, S.B. Lee, D.E Lee, J.O. Guh, K. Back

Biologia plantarum 46:277-280, 2003 | DOI: 10.1023/B:BIOP.0000022265.66891.73

Transgenic rice plants harbouring Bacillus subtilis protoporphyrinogen oxidase (Protox) gene, which is targeted into plastid, were generated by Agrobacterium-mediated transformation using a rice (Oryza sativa L. cv. Dongjin) and their gene integration at T1 generation by Southern and mRNA expression in T2 generation by Northern blotting were analyzed. Their herbicide-resistant trait was further confirmed by in vitro leaf segment assay and in planta bioassays such as seed germination assay and measurement of growth inhibition. The herbicide oxyfluorfen resistance in transgenic rice plants was not very high. The results showed that the Protox from B. subtilis can not be applicable as a gene source to generate a high level oxyfluorfen tolerance in plants.

Changes in Tomato Leaves Induced by NaCl Stress: Leaf Organization and Cell Ultrastructure

O. Sam, C. Ramírez, M.J. Coronado, P.S. Testillano, M.C. Risueño

Biologia plantarum 46:361-366, 2003 | DOI: 10.1023/B:BIOP.0000023878.58899.88

The alterations of organization of leaf tissues and cell ultrastructure as a consequence of salt stress (75 and 150 mM NaCl) were studied in two tomato (Lycopersicum esculentum Mill.) cultivars showing different salinity tolerance. The salinity brought changes in cell shape, volume of intercellular spaces and chloroplast number, shape and size. These characteristics were specific in each cultivar. The ultrastructural changes were also different in the two tomato cultivars studied and the most important ones were in the number and size of starch granules in chloroplasts, the number of electron-dense corpuscules in the cytoplasm, the structure of mitochondria, and number of plastoglobuli.

Effects of Jasmonic Acid on Groundnut During Early Seedling growth

G. Jyothsna Kumari, C. Sudhakar

Biologia plantarum 46:453-456, 2003 | DOI: 10.1023/B:BIOP.0000023894.72554.b2

Exposure of groundnut seeds and seedlings to 25, 100, and 250 μM concentrations of jasmonic acid resulted in a reduction of germination percentage, growth, fresh mass, dry mass, chlorophyll content, chlorophyll stability index, proteins and an increase in free proline content and cell membrane injury. The results suggest the inhibitory effect of jasmonic acid on growth of the groundnut seedlings.

Yoshida, T.: Portraits of Himalayan Flowers

J. Pospíšilová

Biologia plantarum 46:508, 2003 | DOI: 10.1023/B:BIOP.0000041120.80626.8d

Inhibitory Effect of Brassinosteroids on the Flowering of the Short-Day Plant Pharbitis nil

J. Kęsy, A. Trzaskalska, E. Galoch, J. Kopcewicz

Biologia plantarum 46:597-600, 2003 | DOI: 10.1023/B:BIOP.0000041069.27805.89

The effect of exogenous brassinosteroids (BR) on the flowering induction of Pharbitis nil was examined. Generally plants treated with brassinolide and castasterone form less number of flowers than control plants, but degree of flowering inhibition was depended on the concentration and the method of BR application as well as the length of the inductive dark period. In plants regenerated from sub-induced apices treated with brassinolide at concentration of 1 and 10 μM the flower formation was inhibited completely.

Molecular Evidence for the Occurrence of H+-Transporting V-ATPase Subunit D and Two Different Forms of Subunit E in Leaves of the Obligate CAM Species Kalanchoë daigremontiana

R. Ratajczak, T. Pfeifer, M. Drobny, M. Schnölzer, U. Lüttge

Biologia plantarum 46:13-21, 2003 | DOI: 10.1023/A:1022341612852

Membrane proteins of purified tonoplast vesicles from leaves of Kalanchoë daigremontiana Hamet et Perrier were solubilized by the non-ionic detergent Triton X-114 and subsequently separated by MonoQ® anion-exchange chromatography. Special attention was given to the range of molecular masses around 30 kDa comprising the central stalk subunit peptides of the H+-transporting V-ATPase. Three polypeptides of apparent molecular masses of 32, 33 and 34 kDa were separated. Proteolytic fragments were obtained by trypsin digestion. Analysis by matrix-assisted laser desorption ionization (MALDI) mass spectrometry of tryptic fragments of the 32 and 33 kDa peptides and protein data- bank comparisons showed that they are two different forms of subunit E. N-terminal amino acid sequencing of tryptic fragments of the 34 kDa peptide showed that it is subunit D. This work provides for the first time unequivocal molecular evidence that the central stalk of the V-ATPase of the obligate CAM plant K. daigremontiana includes subunit D and different forms of subunit E.

Dynamics of Cadmium Distribution in the Intercellular Space and Inside Cells in Soybean Roots, Stems and Leaves

S. Kevrešan, S. Kiršek, J. Kandrač, N. Petrović, Dj. Kelemen

Biologia plantarum 46:85-88, 2003 | DOI: 10.1023/A:1022366218304

Soybean (Glycine max L.) plants grown in nutrient solution were exposed to 1 mM Cd(NO3)2 for 24 h. Dynamics of distribution of cadmium among its different forms (water soluble, Ca-exchangeable and complexed) in the intercellular space and the ratio of the intercellular and intracellular cadmium in roots, stems and leaves were studied. In roots, in the beginning of treatment the largest portion of Cd was found in the intercellular space and 1 h later Cd content started to decrease, so that between 13- and 24-h treatment an equilibrium was reached in which about 70 % of Cd was found inside cells. In stems, already after 1-h treatment, the Cd concentrations in the cells and intercellular space were similar, the equilibrium being disturbed after 13 h, so that after 24-h treatment 80 % of Cd was found inside cells. In leaves, up to the 13 h Cd distribution showed fluctuation, after that equilibrium was reached, with 70 % of intracellular Cd. The highest contents of all Cd forms in the intercellular space was observed in roots.

Rice Seedlings Release Allelopathic Substances

H. Kato-Noguchi, T. Ino

Biologia plantarum 46:157-159, 2003 | DOI: 10.1023/A:1022337706443

Rice (Oryza sativa L.) seedlings inhibited the growth of hypocotyls and roots of cress (Lepidium sativum L.) seedlings when both seedlings were grown together. Two growth inhibiting substances were found in the culture solution in which rice seedlings were hydroponically grown for 14 d. One growth inhibitor was further purified. This suggests that the rice seedlings may produce growth inhibiting substances, acting as allelochemicals to other plants, and release them from their roots into the environment.

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