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Response of Maize and Sorghum to Excess Boron and SalinityA.M. IsmailBiologia plantarum 46:313-316, 2003 | DOI: 10.1023/B:BIOP.0000022274.72111.12 The effects of 50 mM NaCl and 5, 10, 15 and 20 mM boron on the rate of germination, growth rate, contents of boron, sodium, potassium and chloride, and membrane permeability in maize (Zea mays L.) and sorghum (Sorghum bicolor L.) were studied. Germination rate, lengths of roots and shoots as well as dry matter production in the two tested plants, decreased with the increasing B concentration in nonsaline conditions, and markedly under salinity. Membrane permeability increased by increasing B concentration only under salinity. Increase in B concentration of sorghum was lower under salinity when compared to nonsaline conditions. Contrary to this, increase in B concentration of maize was higher under salinity. Under salinity Na and Cl concentrations increased and K concentration decreased in the both tested plants. Potassium concentration was decreased by B treatments under salinity. |
Growth, nitrate uptake and respiration rate in bean roots under phosphate deficiencyA. Gniazdowska, M. Mikulska, A.M. RychterBiologia plantarum 41:217-226, 1998 | DOI: 10.1023/A:1001862513105 The decrease in inorganic phosphate concentration in bean (Phaseolus vulgaris L. cv. Z³ota 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. |
Nitrate Reductase in Wheat Plants Grown Under Water Stress and Inoculated with Azospirillum spp.H.M. El-Komy, M.A. Hamdia, G.K. Abd El-BakiBiologia plantarum 46:281-287, 2003 | DOI: 10.1023/A:1022819114860 The present investigation has been performed to evaluate nitrate reductase (NR) and nitrogenase activities as well as growth and mineral nutrition of wheat plants grown under drought stress and inoculated with different Azospirillum strains (NR- and NR+). Fresh, dry mass and water content decreased with decreasing soil moisture content, which was accompanied with low soluble sugars and soluble protein content and increase in the total amino acids content. Azospirillum inoculation with either bacterial strain (NR- and NR+) significantly increased the above characteristics even at 40 % moisture content. NR activity decreased in both the shoots and roots by decreasing soil moisture content. NR+ strain exhibited increased root NR activity compared with uninoculated plants or inoculated with NR- strain. However, plants inoculated with NR-strain increased NR activity in the shoot more than in the root of the same plant and in the shoot of control plants. Inoculation with either NR- and NR+ Azospirillum strains gave higher nitrogenase activity than uninoculated control plants. The low N supply (0.5 mM) did not affect nitrogenase activity. NR-strain was less effective than NR+strain in promoting total N-yield, spike numbers and their mass per pot. Azospirillum inoculation exhibited no significant changes in wheat Mg2+ content. However, K+ and Ca2+ have shown significantly increased values. Azospirillum beneficial effect on plant N balance and growth are most probably composed of multiple mechanisms and beneficial NR is one of them. The importance of Azospirillum NR+strains for increasing wheat resistance to water stress is also supported by the obtained data. |
Amelioration of Pb and Mn Toxicity to Arbuscular Mycorrhizal Fungus Glomus intraradices by Maize Root ExudatesR. Malcová, M. GryndlerBiologia plantarum 46:297-299, 2003 | DOI: 10.1023/B:BIOP.0000022270.46561.0c The effect of maize root exudates on the toxicity of lead and manganese to arbuscular mycorrhizal fungus (AMF) Glomus intraradices was studied in vitro by observation of intraradical hyphae regrowth from colonised root segments. Higher heavy metal (HM) concentrations strongly reduced the hyphal growth, however, the inhibitory effect was to a large extent eliminated by the addition of maize root exudates to the media. However, the capacity of exudates to ameliorate HM toxicity was limited and did not operate when a threshold HM concentration was reached. |
Relationship between Soil Nitrate Content and Activities of NADH: and NAD(P)H:Nitrate Reductases in Indian MustardA. Ahmad, I. Khan, Y.P. Abrol, M.Z. AbdinBiologia plantarum 46:295-296, 2003 | DOI: 10.1023/A:1022823315768 The pattern of NADH- and NAD(P)H-specific nitrate reductase (NRs) activities in Indian mustard (Brassica juncea L. Czern. and Coss.) was monitored throughout growth stages. NAD(P)H:NR (EC 1.6.6.2) activity was maximum at early stages of growth (30 days after sowing, DAS), then declined gradually reaching to almost zero at 90 DAS. Contrary to this, NADH:NR (EC 1.6.6.1) activity was low at 30 DAS, then gradually increased till 90 DAS and thereafter, it became constant. The decrease in NAD(P)H:NR activity and increase in the NADH:NR activity were associated with the seasonal decrease in nitrate content in the soil. |
Physiological Response of Maize to Arsenic ContaminationN. Stoeva, M. Berova, Z. ZlatevBiologia plantarum 46:449-452, 2003 | DOI: 10.1023/B:BIOP.0000023893.12939.48 The objective of the study was to investigate the effect of As on some physiological parameters of maize in the early growth phases. Seedlings grown in a climatic box in a Hoagland-Arnon nutrient solution were treated with 0, 2 and 5 mg(As) dm-3 (pH 5.5). After 5 d of As treatment the changes in growth, leaf gas-exchange, chlorophyll (Chl) content, Chl fluorescence, peroxidase activity and lipid peroxidation in roots were recorded. The applied As decreased the growth, leaf area, and biomass accumulation, induced lipid peroxidation and increased peroxidase activity, especially at concentration 5 mg(As) dm-3. It also decreased the Chl, carotenoid (Car) and protein contents. A decrease in the variable to maximum fluorescence ratio (Fv/Fm) indicated lower photosynthetic efficiency. |
Soil Pollution Alters ATP and Chlorophyll Contents in Pisum sativum SeedlingsA.E.A. PäivökeBiologia plantarum 46:145-148, 2003 | DOI: 10.1023/A:1022311902355 Pisum sativum L. cv. Phenomen plants were grown in pots in greenhouse and their growth, and ATP and chlorophyll (Chl) a and b contents were assessed after 9-d exposure to sodium arsenate [0.04 and 0.07 mmol kg-1(soil)], or to lead acetate [2.0 and 4.0 mmol kg-1(soil)], or zinc acetate [5.3 and 9.3 mmol kg-1(soil)]. The luciferin-luciferase method was used for ATP analyses. Soil pollution reduced significantly the growth, but the low toxicant concentrations elevated the cotyledon and shoot ATP concentrations per fresh matter content. The ATP/Chl ratio was increased in the zinc-treated seedlings as compared with the respective controls. The ATP concentration and a number of growth parameters were negatively correlated, and thus the high ATP content might contribute to the significantly reduced growth of seedlings. |
Responses of Rice Cultivars to the Elevated CO2D.C. Uprety, N. Dwivedi, V. Jain, R. Mohan, D.C. Saxena, M. Jolly, G. PaswanBiologia 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. |
Decreased amount of reducing sugars in transgenic potato tubers and its influence on yield characteristicsO. Navrátil, L. Fischer, J. Èmejlová, M. Linhart, J. VacekBiologia plantarum 51:56-60, 2007 | DOI: 10.1007/s10535-007-0011-2 This work focuses on the comparison of field characteristics and amounts of reducing sugars in cold-stored tubers of transgenic plants derived from two potato cultivars. The bacterial gene coding for phosphofructokinase under the tuber-specific promoter was used to support the glycolysis in stored tubers. While the tubers from untransformed control plants steadily accumulated reducing sugars during cold storage, the tubers from transformed plants regardless the genotype were characterized by subsequent decrease in the sugar content. After long period of cold storage the greatest reduction in the reducing sugar content was by more than 60 % compared to control. Before the storage, however, the content of reducing sugars was in 80 % of transgenic lines higher than in control ones. The plants evaluated in field trials for their appearance showed any changes in growth characteristics in about 25 % of the transgenic lines. Despite the introduced modification of sugar metabolism the yield of transgenic plants with normal appearance did not differ significantly from the yield of control plants. |
High frequency in vitro propagation of Holarrhena antidysenterica from nodal buds of mature treeK. Mallikarjuna, G. RajendruduBiologia plantarum 51:525-529, 2007 | DOI: 10.1007/s10535-007-0112-y An in vitro method for propagation of Holarrhena antidysenterica Wall. has been developed using nodal explants from mature trees growing in the field. Irrespective of concentrations and combinations of growth regulators used, the axillary and terminal buds sprouted and elongated when inoculated on Murashige and Skoog (MS) medium. The highest numbers of shoots were formed when sprouted shoots were subcultured from MS basal medium onto MS medium containing 2 mg dm-3 N6-benzyladenine (BA) and 0.5 mg dm-3 α-naphthalene acetic acid (NAA). The shoot number further increased upon subculture on MS medium containing 0.5 mg dm-3 BA. By repeated sub-culturing of shoots derived from nodal axillary buds, a high frequency multiplication rate was established. The elongated shoots were excised and rooted in auxin free MS basal medium. Ex vitro rooting of in vitro formed shoots was achieved upon dipping the microshoots for 2 min in 2 mg dm-3 of indole-3-butyric acid solution. Successful field establishment and high (80-90 %) survival of plants was observed. |
Activity of secreted cell wall-modifying enzymes and expression of peroxidase-encoding gene following germination of Orobanche ramosaC. Veronesi, E. Bonnin, S. Calvez, P. Thalouarn, P. SimierBiologia plantarum 51:391-394, 2007 | DOI: 10.1007/s10535-007-0084-y Radicle growth of germinated seed of the root parasite O. ramosa is shown to be rapidly accompanied by secretion of proteins including pectinolytic enzymes, polygalacturonase and rhamnogalacturonase. These secretions peaked between 4 to 8 d after induction of germination and remained constant for some further days in the case of polygalacturonases. After 6 d, germinated seeds secreted proteins which exhibit peroxidase activity. The latter may be correlated with expression of OrPOX1, a putative gene encoding for secreted peroxidase. The involvement of these enzymes in host root attack and haustorium formation by the parasite is discussed. |
Identification of a novel elite genotype for in vitro culture and genetic transformation of cottonS. Jin, X. Zhang, Y. Nie, X. Guo, S. Liang, H. ZhuBiologia plantarum 50:519-524, 2006 | DOI: 10.1007/s10535-006-0082-5 Hypocotyls of cotton (Gossypium hirsutum L.) cultivars cv. YZ-1, Coker 312 and Coker 201 were inoculated on Murashige and Skoog callus induction medium. YZ-1 exhibited a very high regeneration potential, with 81.9 % of the explants inoculated differentiated into embryogenic callus within 8-10 weeks. During the process of callus maintenance (subculture for 1 to 3 years), the total embryos number in Coker 312 and Coker 201 calli dropped sharply, and the percentage of embryo germination decreased. On the contrary, the callus of YZ-1 consistently maintains a high frequency of plant regeneration after long-time subculture. Transgenic kanamycin-resistant calli of Coker 201 partially lost the ability of somatic embryogenesis and plant regeneration. The stress produced by the transformation procedure slightly affected somatic embryogenesis and plant regeneration of YZ-1, which showed minimum loss of plant regeneration ability. |
Micropropagation of Coleus blumei from nodal segments and shoot tipsG. Rani, D. Talwar, A. Nagpal, G. S. VirkBiologia plantarum 50:496-500, 2006 | DOI: 10.1007/s10535-006-0078-1 A rapid and highly-effective method for micropropagation from nodal segment and shoot tip explants was established for Coleus blumei Benth. Nodal segments and shoot tips were inoculated on MS medium containing 0.7 % agar, 3 % commercial sugar, and different combinations of 6-benzyladenine (BA) with indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) or α-naphthaleneacetic acid (NAA). Hundred percent shoot induction from both explants was achieved on the medium containing BA (2 mg dm-3) and NAA (1 mg dm-3). Shoot tips were proved to be the better explant in comparison to nodal segments in having high rate of shoot induction and more number of shoots. The same media conditions were found suitable for shoot multiplication. Multiplied shoots rooted best on MS medium supplemented with IBA (2 mg dm-3). Micropropagated plants were successfully established in soil after hardening, with 100 % survival rate. |
Putrescine Effect on Nitrate Reductase Activity, Organic Nitrogen, Protein, and Growth in Heavy Metal and Salinity Stressed Mustard SeedlingsD.B. Singh, S. Varma, S.N. MishraBiologia plantarum 45:605-608, 2002 | DOI: 10.1023/A:1022360612976 Putrescine effect on nitrate reductase activity, organic nitrogen and protein contents, and plant growth under Cd or Pb (0.1 - 2 mM) and salinity (5 and 100 mM NaCl) stresses was examined in Indian mustard (Brassica juncea L. cv. RH-30) seedlings. Cd or Pb and salinity inhibited nitrate reductase activity and decreased organic nitrogen and protein contents in leaf tissue. The increased nitrate reductase activity induced by putrescine was correlated with increased organic nitrogen and protein contents and growth of plants. |
Multigenerational inbreeding in Succisa pratensis: Effects on fitness componentsF. X. Picó, C. Mix, N. J. Ouborg, J. M. Van GroenendaelBiologia plantarum 51:185-188, 2007 | DOI: 10.1007/s10535-007-0037-5 We examined the effects of repeated inbreeding on fitness components of the long-lived perennial Succisa pratensis (Dipsacaceae). Plants from six populations differing in size were used to establish lines with expected inbreeding coefficients f of 0, 0.5 and 0.75. The effects of different inbreeding levels were measured for seed set, seed mass, percentage germination and seedling relative growth rate. Seed set decreased following one generation of inbreeding and seedling growth rate decreased after two generations of inbreeding. Our study indicated that the mutational load is difficult to purge and that continued inbreeding tends to affect important traits in S. pratensis. Although the partial dominance hypothesis for inbreeding depression seems to account for the results, the overdominance hypothesis cannot be ruled out completely. Overall, we conclude that the response of a long-lived plant, such as S. pratensis, to repeated inbreeding does not differ from that of other plant species with shorter life spans, surely because the mechanisms that account for inbreeding depression are universal for all plant species. |
Moderate water stress affects tomato leaf water relations in dependence on the nitrogen supplyA. L. García, L. Marcelis, F. Garcia-Sanchez, N. Nicolas, V. MartínezBiologia plantarum 51:707-712, 2007 | DOI: 10.1007/s10535-007-0146-1 The responses of water relations, stomatal conductance (gs) and growth parameters of tomato (Lycopersicon esculentum Mill. cv. Royesta) plants to nitrogen fertilisation and drought were studied. The plants were subjected to a long-term, moderate and progressive water stress by adding 80 % of the water evapotranspirated by the plant the preceding day. Well-watered plants received 100 % of the water evapotranspirated. Two weeks before starting the drought period, the plants were fertilised with Hoagland's solution with 14, 60 and 110 mM NO3 - (N14, N60 and N110, respectively). Plants of the N110 treatment had the highest leaf area. However, gs was higher for N60 plants and lower for N110 plants. At the end of the drought period, N60 plants showed the lowest values of water potential (Ψw) and osmotic potential (Ψs), and the highest values of pressure potential (Ψp). N60 plants showed the highest Ψs at maximum Ψp and the highest bulk modulus of elasticity. |
Genetic engineering of Oryza sativa by particle bombardmentD. Grewal, R. Gill, S. S. GosalBiologia plantarum 50:311-314, 2006 | DOI: 10.1007/s10535-006-0028-y Genetic engineering of rice (Oryza sativa L. cv. Pusa basmati 1) using synthetic Cry1Ac gene has been achieved by "particle bombardment". Scutellar tissues excised after 5 - 6 d from mature seeds cultured on induction medium were bombarded using gold particles coated with a mixture of Cry1Ac and marker genes on medium with osmoticum. Bombarded tissues were subjected to 30 mg dm-3 hygromycin selection for two cycles. The selected calli after GUS assay were transferred to shoot regeneration medium. Regenerated shoots were rooted and plantlets (T0) were grown to full maturity. Polymerase chain reaction (PCR) analysis of T0 plants using Cry1Ac specific primers revealed the presence of Cry1Ac gene in 65 % plants. Phenotypic assay, β-glucuronidase assay and PCR during T1 generation revealed the inheritance of the Cry1Ac and marker genes along with the native plant genes. |
Silicon increases boron tolerance and reduces oxidative damage of wheat grown in soil with excess boronA. Gunes, A. Inal, E. G. Bagci, S. Coban, O. SahinBiologia plantarum 51:571-574, 2007 | DOI: 10.1007/s10535-007-0125-6 The effect of silicon on the growth, boron concentrations, malondialdehyde (MDA) content, lipoxygenase (LOX) activity, proline (PRO) and H2O2 accumulation, and the activities of major antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX)] and non-enzymatic antioxidants (AA) of wheat grown in soil originally with toxic B concentrations were investigated. Applied of 5.0 and 10.0 mM Si to the B toxic soil significantly increased Si concentration of the wheat and counteracted the deleterious effects of B on shoot growth. The contents of PRO, H2O2, MDA, and LOX activity of wheat grown in B toxic soil were significantly reduced by Si treatments. Compared with control plants, the activities of SOD, CAT, APX and content of AA were decreased by applied Si. Based on the present work, it can be concluded that Si alleviates B toxicity of wheat by preventing oxidative membrane damage and also translocation of B from root to shoot and/or soil to plant. |
Changes in nonpolar aldehydes in bean cotyledons during ageingN. Wilhelmová, P. M. D. N. Domingues, M. Srbová, H. Fuksová, J. WilhelmBiologia plantarum 50:559-564, 2006 | DOI: 10.1007/s10535-006-0088-z Ageing of plant organs is accompanied by an increased production of free radicals what results in membrane lipid peroxidation. Non-polar aldehydes originating from this process interact with the cellular material to form the fluorescent end-products, lipofuscin-like pigments (LFP). Their formation was studied both qualitatively and quantitatively in ageing of bean cotyledons. The concentration of lipofuscin-like pigments increased 9-fold in 14-d-old (senescent) cotyledons in relation to 8-d-old (young) cotyledons. HPLC fractionation patterns indicate changes in their composition during ageing. The LFP increase in old cotyledons was accompanied by elevated levels of non-polar aldehydes that increased during ageing to 167 %. The composition of aldehydes was studied by mass spectrometry. The most abundant fraction in both young and old cotyledon was represented by C12 aldehydes, which comprised both saturated and unsaturated species. We have observed differences in abundances of individual aldehydes between the young and the old cotyledons that might explain the differences in the composition of lipofuscin-like pigments. These results support the involvement of free radicals in plant ageing; however, it is suggested that plant aldehydic products of lipid peroxidation differ from those found in animals. |
Salt Tolerance of In Vitro Established Salt-Tolerant Rice Plants during Further Growth in SoilY. Miki, M. Katoh, S. HisajimaBiologia plantarum 44:463-466, 2001 | DOI: 10.1023/A:1012452406918 In vitro salt tolerant rice plants established by step up treatment with 0.5, 1.0, 1.5 and 2.0 % NaCl at 3-week intervals were examined to determine whether they could grow in potted paddy soil containing 0, 0.55 or 0.75 % NaCl till harvesting. All the control plants were necrotic by the 4th week in the culture. At the 10th week of culture, 100 % of the salt-tolerant plants subjected to 0 or 0.55 % NaCl survived, and 78 % of the plants at 0.75 % NaCl. The Na+ and Cl- contents in the leaves of salt-tolerant plants grown at 0.55 and 0.75 % NaCl were about 4 times of those without NaCl. The ion contents in non-tolerant plants and seedling plants were 10 to 12 times of those in 0 % NaCl treatment. One of the hypotheses to explain the present data is that the in vitro step up salt selection induces the capability to maintain no lethal concentration of NaCl in the leaves. |
Efficient regeneration system from wheat leaf base segmentsK. HalilogluBiologia plantarum 50:326-330, 2006 | DOI: 10.1007/s10535-006-0045-x Efficient plant regeneration system from leaf base segments of wheat (Triticum aestivum L.) was developed. The factors affecting the callus formation and regeneration capacity of leaf segments of two genotypes; Bobwhite and Pavon 76, were investigated. The highest number of somatic embryos (SE) was obtained on Murashige and Skoog medium supplemented with 2 mg dm-3 2,4-dichlorophenoxyacetic acid + 1 mg dm-3 naphthalenacetic acid (14.7 SE per segment). Highest frequency of embryogenic callus (96 %) and somatic embryo formation (24.3 SE per segment) were achieved in the first segments. The highest plantlet regeneration was obtained after transfer of embryogenic calli to regeneration medium supplemented with 1 mg dm-3 kinetin (6.3 plantlets per segment). |
Growth and Metabolism of Senna as Affected by Salt StressA. Arshi, M.Z. Abdin, M. IqbalBiologia plantarum 45:295-298, 2002 | DOI: 10.1023/A:1015117327805 Pot culture experiments were conducted using different NaCl concentrations to assess their impact on the growth and metabolic changes in senna (Cassia angustifolia Vahl.). Five treatments (0, 40, 80, 120, and 160 mM NaCl) were given to the plants at three phenological stages, i.e. at pre-flowering, (45 days after sowing, DAS); flowering (75 DAS) and post-flowering (90 DAS) stages. A significant reduction in the biomass and length of the roots and shoots, photosynthetic rate, stomatal conductance, the total chlorophyll content, protein content, nitrate reductase activity, and reduced nitrogen content of the leaves was observed at each phenological stage with each salt concentration applied. Contrary to this, proline and nitrate contents of the leaves increased markedly. The post-flowering stage was most sensitive to NaCl treatment. |
Steady presence of cadmium and nickel affects root anatomy, accumulation and distribution of essential ions in maize seedlingsI. Maksimoviĉ, R. Kastori, L. Krstiĉ, J. LukoviĉBiologia plantarum 51:589-592, 2007 | DOI: 10.1007/s10535-007-0129-2 When growing in the field, plants are exposed to the effect of heavy metals as soon as the seed comes into contact with the soil solution. Therefore, we found important to study the effect of Cd and Ni on maize exposed to these heavy metals since sowing. The aim of this work was to examine which anatomical changes are induced by continuous intoxication of young maize root system with 0.1 mM Cd and Ni, thus modifying its growth and capacity for water and nutrient uptake. Concomitantly, the effect on concentration and distribution of Cd, Ni and some essential ions (Ca, Mg, Zn, Fe, Cu and Mn) was studied. |
Plant development from microspore-derived embryos in oilseed rape as affected by chilling, desiccation and cotyledon excisionG. Q. Zhang, D. Q. Zhang, G. X. Tang, Y. He, W. J. ZhouBiologia plantarum 50:180-186, 2006 | DOI: 10.1007/s10535-006-0004-6 The present study evaluated the effects of chilling, partial desiccation, cotyledon excision and successive subculture of microspore-derived embryos on plant development in oilseed rape (Brassica napus L.). The results showed that out of the five media, all the genotypes showed the best response when the embryos were cultured on the half-strength Murashige and Skoog medium with 2.0 mg dm-3 benzylaminopurine. A cold treatment for 3 or 5 d further increased frequencies of embryo germination (90.0 %) and plantlet development (58.46 %). Desiccation for one day also increased the embryo germination and plantlet development in all genotypes tested. Cutting the cotyledons of the embryos at late cotyledonary stage significantly increased the frequency of plantlet development. The highest rate of plantlet development was obtained from cultures of embryos sampled with size of less than 4.0 mm. The successive subculture further improved the germination and development of plantlets from embryos. In the genotype ZJU452, the rate of plantlet development reached 99.78 % after the second subculture of embryos. |
Hepatitis B surface antigen expression in NT-1 cells of tobacco using different expression cassettesG. B. Sunil Kumar, T. R. Ganapathi, L. Srinivas, C. J. Revathi, V. A. BapatBiologia plantarum 51:467-471, 2007 | DOI: 10.1007/s10535-007-0098-5 Nicotiana tabacum 1 (NT-1) cells were transformed with four different expression cassettes of hepatitis B surface antigen (HBsAg). The transformed nature of the cells was confirmed by polymerase chain reaction (PCR). The expression levels were assayed by enzyme linked immunosorbent assay (ELISA). The expressivities varied among the different cassettes and the maximum expression of 16.6 ng g-1(f.m.) of cells was noted in pEFEHER transformed cells. Salicylic acid (100 µM) treatment resulted in 1.8 fold increase of expression in pEFEHBS transformed cells. The effect of different concentrations of kanamycin and geneticin was studied on the growth of transformed cells and HBsAg expression. The cell growth was optimum at lower concentrations of the antibiotics, and the maximum expression was noted at 200 mg dm-3 of kanamycin. |
Role of phytohormones in organogenic ability of elm multiplicated shootsJ. Mala, A. Gaudinova, P. Dobrev, J. Eder, M. CvikrovaBiologia plantarum 50:8-14, 2006 | DOI: 10.1007/s10535-005-0068-8 The study presents the comparative analyses of endogenous contents of auxin (IAA), cytokinins (CKs), polyamines (PAs), and phenolic acids (PhAs) in apical and basal parts of elm multiplicated shoots with regard to the organogenic potential. The shoot-forming capacity was higher in the apical part than in the basal part. However, the timing of root formation was in the apical type of explant significantly delayed (compared with the organogenic potential of basal part). Significantly higher contents of free bases, ribosides and ribotides of isopentenyl adenine, zeatin and dihydrozeatin that were found in the apical segments, might be considered as the most important factor affecting in vitro shoot formation. The content of endogenous free IAA was approximately three times higher in the basal shoot parts than in the apical parts. The amounts of putrescine and spermidine were higher in the apical part which generally contains less differentiated tissues than the basal part of shoot. The predominant PhA in both types of explants was caffeic acid, and concentrations of other PhAs decreased in the following order: p-coumaric, ferulic, sinapic, vanillic, chlorogenic, p-hydroxybenzoic and gallic acids. The contents of all determined PhAs in their free forms and higher contents of glycoside-bound p-coumaric, ferulic and sinapic acids, precursors for lignin biosynthesis, were found in the basal parts. |
In vitro regeneration of Trifolium glomeratumP. Kaushal, A. Tiwari, A. K. Roy, D. R. Malaviya, B. KumarBiologia plantarum 50:693-696, 2006 | DOI: 10.1007/s10535-006-0108-z In vitro regeneration of Trifolium glomeratum, a leguminous forage species, was attempted through leaf, petiole, cotyledon, hypocotyl, collar and root explants and two media combinations. Root and collar explants showed no callus induction. Medium with 0.05 mg dm-3 α-naphthaleneacetic acid (NAA) and 0.10 mg dm-3 N6-benzyladenine (BA) was more effective for hypocotyl explant whereas cotyledon and petiole explant were more responsive to 5.0 mg dm-3 NAA and 1.0 mg dm-3 BA. Friable, green calli obtained from petiole explant on this medium showed organogenetic potential. Modified root-inducing medium having 0.21 mg dm-3 indole-3-acetic acid and 2.5 % sucrose was successful for root induction and plantlets were successfully transferred to field after hardening and Rhizobium inoculation. |
Identification and sequence analysis of cDNA fragments relative to ovary development of Cymbidium hybridium after pollinationX. Q. Chen, C. G. Wang, Y. Zhang, W. Q. Song, R. Y. ChenBiologia plantarum 51:249-256, 2007 | DOI: 10.1007/s10535-007-0050-8 In this study, seven cDNA fragments of genes, differentially expressed in ovaries after pollination in Cymbidium hybridium, were identified and characterized by mRNA differential display reverse transcription polymerase chain reaction (DDRT-PCR). Four (CDD-313, CDD-272, CDD-265, CDD-243) among these seven cDNA fragments showed no significant homology with ESTs or genes in the databases of NCBI; another three (CDD-193, CDD-218, CDD-470) showed significant homologies with sequences encoding components of an ABC-type transporter, a GTPase and 40S ribosomal S3 proteins (RPS3), respectively. The differential expression patterns of them were confirmed by reverse Northern dot blot analysis. More interestingly, CDD-470 appeared to be present and highly expressed in the pollinated ovaries and encoded a new factor of RPS3 participating in cell growth and proliferation. We deduced that this 40s ribosomal S3 like protein was involved in ovary development of orchids. |
Contrasting foliar responses to drought in Quercus ilex and Phillyrea latifoliaR. Ogaya, J. PenuelasBiologia plantarum 50:373-382, 2006 | DOI: 10.1007/s10535-006-0052-y Leaf morphology, longevity, and demography were examined in Quercus ilex and Phillyrea latifolia growing in a holm oak forest in Prades mountains (northeast Spain). Four plots (10 × 15 m) of this forest were submitted to an experimental drought during three years (soil moisture was reduced about 15 %). Leaf area, thickness and leaf mass per area ratio (LMA) were measured in sun and shade leaves of both species. Leaf longevity, the mean number of current-year shoots produced per previous-year shoot (Sn/Sn-1), the mean number of current-year leaves per previous-year shoot (Ln/Sn-1), and the percentage of previous-year shoots that developed new ones were measured once a year, just after leaf flushing. LMA and leaf thickness increased since leaf unfolding except in summer periods, when stomatal closure imposed low photosynthetic rates and leaves consumed their reserves. LMA, leaf area, and leaf thickness were higher in Q. ilex than in P. latifolia, but leaf density was higher in the latter species. Drought reduced the leaf thickness and the LMA of both species ca. 2.5 %. Drought also increased leaf shedding up to ca. 20 % in Phillyrea latifolia and decreased it up to ca. 20 % in Q. ilex. In the later species, Sn/Sn-1 decreased by 32 %, Ln/Sn-1 by 41 %, percentage of shoots developed new ones by 26 %, and leaf area by 17 %. Thus the decrease of leaf number and area was stronger in the less drought-resistant Q. ilex, which, under increasingly drier conditions, might lose its current competitive advantage in these Mediterranean holm oak forests. |
An efficient in vitro propagation of Aristolochia indicaE. V. Soniya, M. SujithaBiologia plantarum 50:272-274, 2006 | DOI: 10.1007/s10535-006-0018-0 A rapid and efficient in vitro plant regeneration method was developed for Aristolochia indica. Multiple shoot formation was induced from shoot tip and nodal explants on Murashige and Skoog (MS) medium with 1 - 6 mg dm-3 2-isopentenyl-adenine (2-iP) or 1 - 4 mg dm-3 6-benzyladenine (BA). Maximum number of shoots were induced with 5 mg dm-3 2-iP alone (about 12 - 14 shoots). Shoot differentiation occurred directly from the leaf bases as well as from the internodes when cultured on 1 - 4 mg dm-3 BA and 0.8 - 2 mg dm-3 α-naphthaleneacetic acid (NAA) containing medium. Regeneration from the callus occurred when the calli initiated on MS medium containing 0.6 - 4 mg dm-3 NAA in combination with 0.8 - 3 mg dm-3 BA were transferred to 1 - 6 mg dm-3 BA alone containing medium. Elongated shoots were separated and rooted in MS medium containing 1 mg dm-3 indole-3-butyric acid. These were then transferred to soil after gradual acclimatization. |


