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Статья научная
The chlorophyll, proximate and mineral compositions of four elite yam varieties grown under aeroponic and field systems were investigated. The yam varieties used were TDa 98/01176, TDr 95/18544, TDr 95/19177 and TDr 95/19158. One node vines were planted in polythene bags for four weeks and transferred to aeroponics and field system respectively. The chlorophyll a, b and total chlorophylls of field grown varieties of TDr 95/18544, TDr 95/19177 and TDr 95/19158 were all significantly lower than that of aeroponics system. Chlorophyll ‘a’ concentration was higher than that of chlorophyll ‘b’ in all the field and aeroponic grown varieties except for aeroponics grown TDr 95/19177. Leaf moisture, crude fibre content of aeroponics grown yam seedlings were significantly (p˂0.05) higher than those of the field system. The nitrogen (N) content of TDa 98/01176 was significantly (p˂0.05) higher for the field sample compared to that of aeroponic system. There was no significant (p˃0.05) difference in Nitrogen composition for the other varieties. Calcium (Ca), magnesium (Mg), potassium (K), sodium (Na) and phosphorus (P) content of the field samples were not significantly different from that of aeroponics system. The differences in chlorophyll content in this study may be due to differences in exposure to sunlight. This could enhance yam mineral concentration thereby improving nutrition.
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Chromaffin cell activity in Heteropneustes fossilis exposed to artificial photoperiod
Статья научная
The study deals with the effect of artificial photoperiod on the interrenal and chromaffin tissues and physiological stress parameters in the teleost, Heteropneustes fossilis. Fishes were exposed to photoperiods of continuous illumination 24L:0D and continuous darkness 0L:24D for a short period (24hrs) and a long period (10 days) following which the histology of the tissues was carried out for morphometric measurements of the interrenal and chromaffin cells and blood was analyzed for the physiological stress parameters (plasma glucose, plasma chloride, plasma protein and N:L ratio). No changes in the physiological variables were observed following any of the treatments for short periods. Plasma glucose, plasma chloride and plasma protein levels increased significantly (p
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Статья научная
Fish live in the aquatic column; they are facing challenge for surviving from pollutants, particularly from various chemical fertilizers and pesticides used in or adjacent paddy fields or flood lands. They can be exposed to animals in a number of ways. Hence, an attempt has been made to know the presence of profenofos and carbosulfan residues in different tissues viz., liver, muscle, gill and kidney of Labeo rohita exposed to sublethal and lethal concentrations for 15 days. The results of the present study revealed that, prolonged exposure to sublethal concentrations of profenofos and carbosulfan in Labeo rohita leads to increased accumulation of residue. Thus repeated or continuous exposure to low concentrations of pesticides can lead to high residue concentrations without mortalities. Thus the uptake and persistence of profenofos and carbosulfan depends not only on a number of physical and chemical conditions but also varies according to the biological conditions.
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Статья научная
Background: Heavy metal-induced pollution of water bodies has emerged out as a major environmental menace for the modern world in the twenty first century. Many industrial waste waters contain heavy metals including Chromium, which plays a major role in polluting our water and agricultural sustainability in the long run. Due to heavy anthropogenic manoeuvres chromium is released as a waste product from various industries such as electroplating, battery and smelters, leather tanning, textile printing etc. The compounds of Chromium have been known to be strong carcinogens and mutagens that can reach the target organs of human through drinking water and agricultural crops. Chromium is often admixed with industrial effluents that are used for irrigation. Purpose: The uptake of excess concentrations of heavy metals through this effluent irrigation adversely affects plant growth and development. The alternation in plant growth is correlated with the disruption of the physiological disturbances and genotoxicity in plant cell. Results: After the exposure to chromium at five concentrations (12.5, 10, 7.5, 5, and 2.5 mM) respectively the seed germination was adversely affected along with root length inhibition. At higher doses (5 mM onwards) chromium exhibited nucleolar disintegration (by AgNOR protein leaching). In germinating root tip cells above suboptimal concentration (2.5 mM) chromium stands out as potential Phyto-genotoxicant with other toxic effects i.e., lipid peroxidation, electrolyte leakage due to membrane disruption, ROS generation (histological staining of hydroxyl and superoxide radical generation) root cell apoptosis (by Evans blue staining) and disruption of root metabolic activity by inhibition of dehydrogenase activity (by 2,3,5-Triphenyl tetrazolium chloride (TTC) staining methods). Conclusion: These observations constitute a warning signal about the risks of the widespread and increasing presence of chromium into environment especially in agricultural point of view which demands a high throughput evaluation of chromium for its effects on other organisms, even on human health, due to large use of chromium compounds in different gadgets. Lathyrus sativus L. is an excellent model plant for the study of environmental ecotoxicology of different genotoxicants. Implication: Regulatory monitoring and assessment of plant health is necessary for the better understanding of mechanism of action of chromium and to reduce Cr contamination through seeds and the resultant vital genome loss is cash crops.
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Cold hardening prevents H 2O 2-induced programmed cell death in maize coleoptiles
Статья научная
An influence of cold hardening (8 °С, 7 days) on the respiration intensity, the content of reactive oxygen species and DNA fragmentation in coleoptiles of maize etiolated seedlings of different ages and a possibility of the cold hardening to prevent execution of the cell death, induced by treatment with 10 mM H 2O 2 (for 4 hours) of seedlings have been studied. It has been shown that H 2O 2 induces total DNA fragmentation in coleoptiles of maize etiolated seedlings, and a preliminary cold hardening prevents this process.
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Cold hardiness of apple and changes in dehydrin composition
Статья научная
The work was aimed to study the degree of wood damage through artificial freezing and dehydrin changes in apple bark. The relation between apple tree cold hardiness and dehydrin accumulation and degradation rate was established.
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Cold storage of plant tissue cultures - effect of sucrose
Статья научная
Explants of normal (non-transformed) carrot ( Daucus carota L.) tissue, scorzonera crown gall ( Scorzonera hispanica L.) and carrot tissues transformed with Agrobacterium tumefaciens (all cultured in vitro ) were planted in little glass jars with 6 cm3 of nutrition media containing 3, 5, 7 or 9% sucrose and maintained at +3 ºC for 6, 8, 10 and 12 months. Viability of tissue cultures after cold storage was estimated by the degree of tissue necrosis, per cent of explants exhibiting growth resumption and intensity of the resumpted growth. Little or no growth was observed during cold storage of scorzonera and normal carrot tissues, whereas transformed carrot tissues showed significant growth. Dry matter content of tissues increased with an increase of sucrose concentration in the medium and failed to change during cold storage of scorzonera and normal carrot tissues. The dry matter content of the transformed carrot tissues fell down during cold storage due to the increase of fresh weight. The viability of all tissue cultures was preserved better and for a longer time with 7% sucrose, than with 3, 5 and 9%. Transformed carrot and tobacco callus tissues preserved cell viability better than non-transformed ones. Cycles consisting from long subcultures (several months) at 3 ºC interrupted by short subcultures (several weeks) at 26 ºC were applied in order to storage of tissue cultures for several years.
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Combined effects of zinc and high irradiance stresses on photoinhibition of photosynthesis in bean
Статья научная
Seedlings of bean plants (Phaseolus vulgaris L.Sel 9) were grown for 2 weeks with half strength Hoagland solution containing 0 ppm (deficient), 5 ppm (sufficient) and 50 ppm (excess) ZnSO4.7H2O. Changes in photosynthetic pigments, soluble proteins, soluble starch, photosystem (PSII) activities and thylakoid membrane proteins were investigated. The degree of photoinhibition was determined by the ratio of variable to maximum chlorophyll (Chl) fluorescence (Fv/Fm). Photosynthetic pigments, soluble proteins and soluble starch decreased significantly in Zn-deficient and Zn-excess leaves. Though the maximum quantum yield of primary photochemistry (Fv/Fm), maximum variable fluorescence (Fv) were significantly decreased to a greater extent in Zn-excess leaves the restoration was excellent. The exogenous electron donors, diphenylcarbazide (DPC) and NH2OH restored the loss of PSII activity in Zn-deficient and Zn-excess leaves. A slight degradation 33, 28-25, 23 and 17 kDa polypeptides were observed in the Zn-deficient and Zn-excess leaves. Upon recovery from HI stress, the Zn-excess leaves restored the 47, 33, and 28-25 kDa polypeptides.
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Статья научная
Parthenium ( Parthenium hysterophorus L . ) has become an invasive woody plant in recent times in many parts of the world. It is rapidly spreading in Pakistan, causing severe damage to the agriculture productivity of the country. A laboratory scale study was conducted in order to evaluate the allelopathic effect of exotic herb Parthenium on chickpea ( Cicer arietinum ) by morphological approaches. Experiments were carried out in petri plates supplemented with aqueous extracts of root, stem, leaves and flowers of Parthenium . Pronounced variations were noticed for allelopathic activity of different plant parts at different concentrations. Parthenium extracts either inhibited or promoted the germination of seeds and seedling growth of chickpea. Results showed that aqueous extracts of root, leaves and flowers significantly reduced the germination and seedling growth. The maximum inhibition was observed with the extract of leaves and flowers as well as the highest inhibition was observed at higher concentrations i.e. 7.5 and 10%. It is concluded that aqueous root, stem, leaf and flower extracts of Parthenium contain allelopathic compounds inhibits seed germination and seedling growth of chickpea at higher concentrations.
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Статья научная
Induction and accumulation of osmotin-like proteins are crucial components of innate immune responses in plants challenged with pathogens. One of these proteins, PR5 and PA13 , are abundantly secreted and are able to elicit plant defenses, however, their native function in potato plants infected with Phytophthora infestans remains unknown. Here, the pathway signaling of the two genes were monitored in potato plants at early points of infection with P. infestans using quantitative real-time PCR (qPCR). Our data demonstrated significant gene expression variance of the two genes in infected plants as compared to the non-infected controls. It is also notable that PA13 gene had higher expression than PR5 in the resistant cultivar 'Sponta' as compared to the susceptible one 'Draga' with a maximum expression for PR5 (3.5 and 1.2-fold) and PA13 (8.2 and 2.7-fold) respectively, at 48 hours post infection. The obtained results suggested that PR5 and PA13 genes, positively regulate P. infestans -resistance in potato plants during disease progress, which can offer testable hypotheses that will need straight upcoming experiments to define how the PR5 and PA13 pathway signaling may be specified in potato defense system.
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Статья научная
An attempt has been made to compare the effects of conventional phytohormones like IAA, NAA, BAP to the recent hormones viz., JA and SA in callus induction in blackgram using hypocotyl as explant source. Instead of testing the hormone individually, a combination of hormones was used to induce callus and organogenesis. A significant callusing response was noticed in MS medium supplemented with 0.5 ppm of 2,4-D and 1 ppm of IAA. Likewise, Salicylic acid at 1 ppm induced high percentage of callus induction proving its efficiency in inducing the root formation. Jasmonic acid induced a high percentage of callus induction at 1.5 ppm and greater rooting response than SA. Organogenic callus was observed at JA and SA supplementation. The combination of NAA, BAP and SA showed that 0.75 & 1.5 ppm of NAA, 1 ppm of BAP and 0.5 ppm of SA showed a better response in culture medium. Thus, the combination of these hormones seems serve as efficient growth supplements for in vitro culture of many agricultural crops.
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Статья научная
Cowpea is a commonest and affordable legume widely consumed in developing nation of the world. Salicylic (SA) and Gibberellic (GA) acids serve to play prominent roles in induction of growth and development in cowpea. However, heavy metal such as arsenic is one of the major pollutant commonly encountered and its exposure to plant often result in alteration in physiological and biochemical functions. Therefore the aim of this work was to examine the effects of Salicylic and Gibberellic acid on lipid peroxidation and antioxidant potentials of three cultivars of Vigna unguiculata under heavy metal toxicity. Seeds of three cowpea cultivars (Ife Brown, ITOK-768-18and ART 98-12) were sorted and each of the three cultivars were soaked in SA [0 control, (75, 150) mg/L} and GA [0 control, (75, 150) mg/L} respectively. The seeds (n=5) were planted in a completely randomised design in pots of soil containing each of 0, 250 and 500mg/L sodium arsenate. Vitamin C, otal flavonoid, phenolic, lipid peroxidation, superoxide dismutase, peroxidase, catalase activities in leaves were determined on day 90 using spectrophotometry The results show that in comparing treatment with the control among the three cultivars, superoxide dismutase, peroxidase and catalase, vitamin C, total flavonoid and phenolic were increased by (3, 4, 2, 12, 4 and 3 folds respectively), in Ife brown; (2, 5, 12, 12, 5 and 3 folds respectively), in ART 98-12; (4, 3, 14, 5 and 4 folds respectively), in ITOK-768-18 in the leaves of 250mg/L sodium arsenate-treated soil with SA (150mg/L). Lipid peroxidation were reduced by (5 and 3 folds respectively), in Ife brown and ITOK-768-18 in 250mg/L sodium arsenate-treated soil with SA (150mg/L) but was reduced by 3 folds in 250mg/L sodium arsenate-treated soil with SA (75mg/L) for ART98-12. Salicylic and gibberellic acids therefore reduced lipid peroxidation, enhanced antioxidant potentials of Vigna unguiculata to increase tolerance and promote growth during heavy metal toxicity.
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Comparative morpho-biochemical responses of wheat cultivars sensitive and tolerant to water stress
Статья научная
Water stress is likely the most important factor that adversely affects plant growth and development. In this study two wheat cultivars Gemmieza-7 (sensitive) and Sahel-1 (tolerant) were subjected to water stress and compared in terms of growth parameters (growth vigor of root and shoot), water relations (relative water content and saturation water deficit ) and protein as well as nucleic acids (DNA and RNA) content in flag leaves of both cultivars. In general, water stress caused noticeable reduction in almost all growth criteria of root, shoot and flag leaf which was consistent with the progressive alteration in water relations, protein and nucleic acids content of both cultivars during grain filling. Furthermore, degree of leaf succulence and degree of leaf sclerophylly were severely affected by water stress in both wheat cultivars. In relation to wheat cultivar, the sensitive was more affected by water stress than the tolerant one. Generally, the application of salicylic acid, trehalose or their interaction induced marked increase in growth vigor of root and shoot, water relations and protein as well as nucleic acids in flag leaves of both wheat cultivars in compare with control and water stressed plants. In conclusion, Sahel-1 has suitable mechanisms to enable it to respond more effectively to water stress than Gemmieza-7.
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Статья научная
In the present study, 20 chilli cultivars were characterized based on morphology as it serves as discrete identification indicator and also propose to evaluate cultivar diversity for yield related parameters. Among the 20 cultivars, different quantitative and qualitative morphological traits like, hypocotyl pubescence, hypocotyl colour, cotyledon leaf shape, cotyledon leaf colour, cotyledon leaf width and cotyledon leaf length were studied. A stem length to first bifurcation ranged from 10.80 cm (LCA-424) to 26.33 cm (LCA-620) among the 20 cultivars, taller and shorter stems, taller, wider plant, longer and wider leaves were noticed. Hence, this character could be used for varietal identification. Fruit, fruit length, fruit width, pedicel length, dry fruit weight, seed weight and seed size might be efficiently used for different the chilli cultivars. Fruit positions were divided into two groups viz. , Pendent and Erect. Among them, maximum number of genotypes had pendent fruits while only one by Mycoteja produced erect fruits...
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Comparative phytochemical evaluation of the aerial parts of Neolamarckia cadamba (Roxb.) Bosser
Статья научная
Neolamarckia cadamba (Roxb.) Bosser is an important traditionally using medicinal plant. Almost all parts of plants are used for medicinal purposes against numerous diseases. In this present study, presence of secondary metabolites was compared between bark, leaves, ripe and unripe fruits of plant using preliminary phytochemical screening using standard methods in solvents having different degree of polarity- acetone, benzene, methanol, petroleum ether and water. Comparative study indicated that polar solvents were superior in extracting secondary metabolites as compared to non- polar. This present study also suggested leaves were high on secondary metabolites followed by ripe fruits and bark whereas unripe fruits found to be on lower level on major classes of secondary metabolites.
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Статья научная
The Plectranthus amboinicus is known for its medicinal properties. The extracts from this plant material are used to treat different diseases which include cold, respiratory disorders, digestive problems, skin infections, cough, chronic asthma, bronchitis, hiccups, etc. The present study aimed to compare and evaluate the antioxidant property of two aerial parts of the plant, the stem and the leaf extracts of Plectranthus amboinicus . The different type of extracts was prepared with fresh leaves, fresh stem and dried leaves, with methanol as the solvent for extraction. The antioxidant potential of each extract was checked and the result obtained showed the fresh stem extract had the highest antioxidant activity. The study result shows that the methanolic extracts of dried leaves have Tannins, flavonoids, phenol and reducing sugars. The methanolic extract of fresh leaves and fresh stem extracts showed the presence of Tannins, flavonoids, quinone, steroids, phenols and reducing sugars. The phenolic content of the methanolic extract of the stem is high compared to fresh and dried leaves. The anti-oxidant potentials were assayed through the FRAP, FTC and TBA assays, the results showed that the free radical scavenging property of the methanolic extract of the stem is high compared to the fresh and dried leaves. The methanolic stem extract has high phenolic content and also shows high free radical scavenging properties than the methanolic extract of fresh and dried leaves.
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Статья научная
The development of drought tolerant genotypes for peanuts has now become a priority due to the growing number of drought-prone areas. The effects of drought stress on nitrogen metabolism was studied in leaves of two groundnut cultivars with differential sensitivity to drought stress, K-134 (drought tolerant) and JL-24 (drought sensitive) subjected to different regimes of water stress conditions for a duration of 12 days. The total protein content in leaves of both cultivars declined with progressive accumulation of free amino acid levels. Concurrently, the protease activity in the tissues was also increased. Ammonia content was increased in both cultivars and comparatively higher ammonia levels were recorded for cv. JL-24. A gradual increase in the activities of key enzymes involved in nitrogen metabolism such as glutamine synthetase (GS), glutamate synthase (GOGAT), glutamate dehydrogenase (NADH-GDH and NADPH-GDH), aspartate aminotransferase (AAT) and alanine aminotransferase (ALAT) was observed in both cultivars subjected to water stress. The increase in enzyme activities was more pronounced in the drought tolerant than in the drought sensitive cultivar. Contrarily, the activities of nitrate reductase (NR) and nitrite reductase (NiR) were decreased in the stressed plants. The extent of decrease was more in cv. K134 than cv. JL-24. The results indicate that drought tolerance of cultivar K-134 may be attributed at least in part to the ability to shift the metabolic rate leading to a greater accumulation of amino acids coupled with lower levels of ammonia and largely by reassimilation as evidenced by relatively greater activities of GS and GOGAT in the tissue. The physiological importance of enzyme alterations under water stress was investigated in relation to plant metabolism.
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Статья научная
The thermogenic mechanisms were measured in the two small rodents, Eothenomys milletus and Apodemus chevrieri in Hengduan mountain region during cold exposure. The main results were as follows: 1. RMR and NST incredsed 68.34%, 36.34% during the cold exposure in E.miletus, RMR and NST incredsed 32.84%, 56.17% during the cold exposure in A. chevrieri, respectively. 2. During cold exposure, total protein content in liver, the total protein content(TP) and mitochodrnal protein content(MP) in brown adipose tissue (BAT), the content of uncoupling protein (UCP1) were increased in E.miletus, which increased 18.66%, 25.18%, 70.01%, 99.39%, respectively. Total protein content in liver, the total protein content(TP) and mitochodrnal protein content(MP) in brown adipose tissue (BAT), the content of uncoupling protein (UCP1) were increased in A. chevrieri, which increased 18.11%, 33.29%, 34.51%,235.95%, respectively. All of the results indicated that the mechanism of heat production for adaptative changes was similar in two rodents, but it showed different increased amplitude of heat production, it may considered that the difference of heat production was related to origin of species and inhabitats.
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Comparison of nonshivering thermogenesis induced by norepinephrine stress in tree shrews
Статья научная
Nonshivering thermogenesis (NST)is an important thermogenic mechanism for small mammals. Quantitative measurement of NST is usually stimulated by injection of norepinephrine. The injection dosage of norepinephrine (NE)is critical for eliciting the maximum NST. Three empirical equations of NE dosages were often referenced in previous studies: (1)NE (mg / kg)= 2.53W -0.4; (2)NE(mg/kg) = 3.3W -0.458 and (3)NE(mg/kg)= 6.6W -0.458. In the present study, we used tree shrews ( Tupaia belangeri ) as experiment subjects to test the effects of the three dosages of NE on NST. Results showed that all the three dosages of NE could induce the maximum NST for T. belangeri. No significant differences were found in NST among groups and the NST was respectively 2.63±0.12 (formula 1), 2.66±0. 11 (formula 2) and 2.78±0.15 (formula 3). However, when injected with NE dosage from formula 3, the increase of body temperatures was significantly higher than the other two NE dosages (increased 1.5±0. 1 oC (formula 3), 0.8±0. 2 oC (formula 2), and 0.6±0. 1 oC (formula 1), respectively). In order to prevent the death because of hyperthermia, formula 1 or 2 is recommended to be used.
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