Showing papers in "Physiology and Molecular Biology of Plants in 2015"
TL;DR: The results are able to prove the suitability of SCoT and CDDP markers for genetic diversity analysis in chickpea for their high rates of polymorphism and their potential for genome diversity and germplasm conservation.
Abstract: To evaluate the genetic diversity among 48 genotypes of chickpea comprising cultivars, landraces and internationally developed improved lines genetic distances were evaluated using three different molecular marker techniques: Simple Sequence Repeat (SSR); Start Codon Targeted (SCoT) and Conserved DNA-derived Polymorphism (CDDP). Average polymorphism information content (PIC) for SSR, SCoT and CDDP markers was 0.47, 0.45 and 0.45, respectively, and this revealed that three different marker types were equal for the assessment of diversity amongst genotypes. Cluster analysis for SSR and SCoT divided the genotypes in to three distinct clusters and using CDDP markers data, genotypes grouped in to five clusters. There were positive significant correlation (r = 0.43, P < 0.01) between similarity matrix obtained by SCoT and CDDP. Three different marker techniques showed relatively same pattern of diversity across genotypes and using each marker technique it’s obvious that diversity pattern and polymorphism for varieties were higher than that of genotypes, and CDDP had superiority over SCoT and SSR markers. These results suggest that efficiency of SSR, SCOT and CDDP markers was relatively the same in fingerprinting of chickpea genotypes. To our knowledge, this is the first detailed report of using targeted DNA region molecular marker (CDDP) for genetic diversity analysis in chickpea in comparison with SCoT and SSR markers. Overall, our results are able to prove the suitability of SCoT and CDDP markers for genetic diversity analysis in chickpea for their high rates of polymorphism and their potential for genome diversity and germplasm conservation.
75 citations
TL;DR: The role of GB in increasing tolerance to salinity stress in soybean may result from either its antioxidant capacity by direct scavenging of H2O2 or its role in activating CAT activity which is mandatory in scavenging H2 O2.
Abstract: Glycinebetaine is one of the most competitive compounds which play an important role in salt stress in plants. In this study, the enhanced salt tolerance in soybean (Glycine max L.) by exogenous application of glycinebetaine was evaluated. To improve salt tolerance at the seedling stage, GB was applied in four different concentrations (0, 5, 25 and 50 mM) as a pre-sowing seed treatment. Salinity stress in the form of a final concentration of 150 mM sodium chloride (NaCl) over a 15 day period drastically affected the plants as indicated by increased proline, MDA and Na+ content of soybean plants. In contrast, supplementation with 50 mM GB improved growth of soybean plants under NaCl as evidenced by a decrease in proline, MDA and Na+ content of soybean plants. Further analysis showed that treatments with GB, resulted in increasing of CAT and SOD activity of soybean seedlings in salt stress. We propose that the role of GB in increasing tolerance to salinity stress in soybean may result from either its antioxidant capacity by direct scavenging of H2O2 or its role in activating CAT activity which is mandatory in scavenging H2O2.
67 citations
TL;DR: Overall result suggested that lignin accumulation was not affected much in case of developing root however developing stems were significantly affected under drought and salinity stress condition.
Abstract: Aboitic stress such as drought and salinity are class of major threats, which plants undergo through their lifetime. Lignin deposition is one of the responses to such abiotic stresses. The gene encoding Cinnamoyl CoA Reductase (CCR) is a key gene for lignin biosynthesis, which has been shown to be over-expressed under stress conditions. In the present study, developing seedlings of Leucaena leucocephala (Vernacular name: Subabul, White popinac) were treated with 1 % mannitol and 200 mM NaCl to mimic drought and salinity stress conditions, respectively. Enzyme linked immunosorbant assay (ELISA) based expression pattern of CCR protein was monitored coupled with Phlorogucinol/HCl activity staining of lignin in transverse sections of developing L. leucocephala seedlings under stress. Our result suggests a differential lignification pattern in developing root and stem under stress conditions. Increase in lignification was observed in mannitol treated stems and corresponding CCR protein accumulation was also higher than control and salt stress treated samples. On the contrary CCR protein was lower in NaCl treated stems and corresponding lignin deposition was also low. Developing root tissue showed a high level of CCR content and lignin deposition than stem samples under all conditions tested. Overall result suggested that lignin accumulation was not affected much in case of developing root however developing stems were significantly affected under drought and salinity stress condition.
64 citations
TL;DR: Findings revealed that although JA was not helpful for protection of photosynthetic pigments but it modulates the other machinery of plants significantly including various antioxidants positively, while tightly inhibiting stress related processes responsible for lipid peroxidation to make plants tolerant to Ni2+ stress.
Abstract: Jasmonic acid (JA) is a very young candidate of plant growth regulators which is being explored for various antistress properties. Present study deals with the hypothesis that JA can modulate antioxidant mechanism of higher plants with tight regulation of biomembrane peroxidation, making plants tolerant to toxic Ni2+. 2 mM NiCl2 as a source of Ni2+ appeared as sub lethal dose for the growth of 15 days old Glycine max seedlings. Exogenous application of 1 μM and 1 nM JA prior to NiCl2 exposure, made seedlings of Glycine max more tolerant to Ni2+stress as compared to control untreated seedlings. Regulatory inhibition of MDA and H2O2 production by JA with or without Ni2+ treatment made plants more resistant to Ni2+ stress which may be associated with ameliorative activity of antioxidant enzymes system composed of SOD, POD, CAT and APOX. Ascorbate, a secondary metabolite synthesized from D-glucose act as an antioxidant in plant cells. Many fold enhancements in AsA content of Ni2+ treated seedlings supplemented with different concentrations of JA was observed. Significant improvement in AsA levels by JA with or without Ni2+ stress may involve two aspects, either denovo synthesis level regulation of AsA or recycling of AsA from an oxidized form. Improvement in total protein content showed the uplift modulation of transcriptional machinery by JA which was also maintained under Ni2+ stress. Photosynthetic pigments as total chl, chl a and b showed inhibition in presence of Ni2+ stress which was not found much effective under JA supplementation as compared to control. Present findings revealed that although JA was not helpful for protection of photosynthetic pigments but it modulates the other machinery of plants significantly including various antioxidants positively, while tightly inhibiting stress related processes responsible for lipid peroxidation to make plants tolerant to Ni2+ stress.
50 citations
TL;DR: The results suggest that used SSR markers are efficient for measuring genetic diversity and relatedness as well as identifying varieties of soybeans.
Abstract: Sixteen polymorphic Simple sequence repeat (SSR) markers were used to determine the genetic diversity and varietal identification among 38 soybean (Glycine max (L) Merr) genotypes which are at present under seed multiplication chain in India A total of 51 alleles with an average of 222 alleles per locus were detected The polymorphic information content (PIC) among genotypes varied from 0049 (Sat_243 and Satt337) to 0526 (Satt431) with an average of 0199 The pair wise genetic similarity between soybean varieties varied from 056 to 097 with an average of 0761 These 16 SSR markers successfully distinguished 12 of the 38 soybean genotypes These results suggest that used SSR markers are efficient for measuring genetic diversity and relatedness as well as identifying varieties of soybeans Diverse genetic materials may be used for genetic improvements of soybean genotypes
48 citations
TL;DR: The results confirmed that both genetic and phenotypic diversity in a combined way could efficiently evaluate the variation present in different sesame accessions in any breeding program.
Abstract: Sesame is an important ancient oilseed crop of high medicinal value. In the present study, 37 characters including both quantitative and qualitative traits of sixty genotypes were characterized following IPGRI morphological descriptors for sesame. Multivariate analysis was computed to distinguish the varieties into different groups. Though thirty six microsatellite markers including genomic and Est-SSR markers were initially selected, but, finally, the accessions were genotyped by eight polymorphic primers. Altogether, 27 alleles were detected among the 60 genotypes, with an average of 3.37 alleles per locus. The number of alleles ranged from 2 to 6 alleles. From data of microsatellite markers, dissimilarity coefficients between varieties were computed following Jaccard’s coefficient method. Principal co-ordinate analysis was used to represent the varieties in bi-directional space. Dendrogram was constructed using NJ method based on dissimilarity matrix. Cluster analysis based on morphological and molecular marker classified sesame genotypes into two major groups. Mantel test showed an insignificant correlation between phenotypic and molecular marker information. The genotypes belonging to the same geographical area did not always occupy the same cluster. The results confirmed that both genetic and phenotypic diversity in a combined way could efficiently evaluate the variation present in different sesame accessions in any breeding program.
42 citations
TL;DR: The study provides insight into the efficacy of RAPD, ISSR and DAMD to analyse the genetic variation existing in the wild Musa germplasm, which can further be exploited for quality trait improvement and domestication of such important horticultural crops.
Abstract: North east India is considered as one of the major biodiversity hotspots worldwide and centre of origin of several plant species including Musa. Musa acuminata Colla is known to be one of the wild progenitors of cultivated bananas and plantains. Three single primer based DNA marker techniques viz., random amplified polymorphic DNA (RAPD), inter simple sequence repeat (ISSR) and directed amplification of minisatellites DNA (DAMD) were used for diversity diagnostics among 25 genotypes of wild M. acuminata collected from Meghalaya province of north east India. A total of 58 primers (26-RAPD, 21-ISSR, and11-DAMD) yielded 451 DNA fragments, of which 395 (87.58 %) were found to be polymorphic in nature. The polymorphic information content (PIC) values were almost identical for each marker system. The resolving power of the marker system was found to be highest in RAPD (3.96) whereas ISSR resolved highest marker index (16.39) in the study. Selected amplicon data obtained through single primer amplification reactions were utilized for determination of diversity within and among the populations of M. acuminata. Nei's genetic differentiation (Gst) value (0.451) indicated higher proportion of the genetic variation within the populations which is supported by the AMOVA analysis (88 %). The study provides insight into the efficacy of RAPD, ISSR and DAMD to analyse the genetic variation existing in the wild Musa germplasm, which can further be exploited for quality trait improvement and domestication of such important horticultural crops. The genetic diversity based population structure may shed light on the genetic basis of speciation and evolution of various species within the genus Musa.
40 citations
TL;DR: As tolerance potential of Withania plants on one hand advocates its prospective use for remediation under proper supervision and on the other demonstrates possible threat of As entry into humans due to medicinal uses.
Abstract: Withania somnifera has been an important herb in the Ayurvedic and indigenous medical systems for centuries in India However, these grow as weeds mostly in the wastelands, which receive contaminated water from municipal and industrial sources In the present investigation, plants of Withania somnifera were exposed to various concentrations of arsenate (AsV) and arsenite (AsIII) (0, 10, 25, 50, 100 μM) for 10 days and analysed for accumulation of arsenic (As) and physiological and biochemical changes Plants showed more As accumulation upon exposure to AsIII (320 μg g−1 DW in roots and 161 μg g−1 DW in leaves) than to AsV (173 μg g−1 DW in roots and 100 μg g−1 DW in leaves) after 10 days of treatment Consequently, AsIII exposure caused more toxicity to plants as compared to that AsV, as evaluated in terms of the level of photosynthetic pigments and oxidative stress parameters (superoxide, hydrogen peroxide and lipid peroxidation), particularly at higher concentrations and on longer durations Plants could tolerate low concentrations (variable for AsIII and AsV) until longer durations (10 days) and high concentrations for shorter durations (1–5 days) through increase in antioxidant enzymes and by augmented synthesis of thiols In conclusion, As tolerance potential of Withania plants on one hand advocates its prospective use for remediation under proper supervision and on the other demonstrates possible threat of As entry into humans due to medicinal uses
37 citations
TL;DR: The identified ESTs reveal a major portion of the stress responsive transcriptome that may prove to be a vent to unravel molecular basis underlying tolerance of pearl millet (Pennisetum glaucum) to drought stress.
Abstract: Pearl millet (Pennisetum glaucum) is an important cereal of traditional farming systems that has the natural ability to withstand various abiotic stresses. The present study aims at the identification and validation of major differentially expressed genes in response to drought stress in P. glaucum by Suppression Subtractive Hybridization (SSH) analysis. Twenty-two days old seedlings of P. glaucum cultivar PPMI741 were subjected to drought stress by treatment of 30 % Polyethylene glycol for different time periods 30 min (T1), 2 h (T2), 4 h (T3), 8 h (T4), 16 h (T5), 24 h (T6) and 48 h (T7) respectively, monitored by examining the RWC of seedlings. Total RNA was isolated to construct drought responsive subtractive cDNA library through SSH, sequenced to identify the differentially expressed genes in response to drought stress and validated by qRT-PCR.745 ESTs were assembled into a collection of 299 unigenes having 52 contigs and 247 singletons. All 745 ESTs were submitted to ENA-EMBL databases (Accession no. HG516611- HG517355). After analysis, 10 differentially expressed genes were validated namely Abscisic stress ripening protein, Ascorbate peroxidase, Inosine-5′-monophosphate dehydrogenase, Putative beta-1, 3-glucanase, Glyoxalase, Rab7, Aspartic proteinase Oryzasin, DnaJ—like protein and Calmodulin—like protein by qRT-PCR. The identified ESTs reveal a major portion of the stress responsive transcriptome that may prove to be a vent to unravel molecular basis underlying tolerance of pearl millet (Pennisetum glaucum) to drought stress. These genes could be utilized for transgenic breeding or transferred to crop plants through marker assisted selection for the development of better drought resistant cultivars having enhanced adaptability to survive harsh environmental conditions.
36 citations
TL;DR: PGPR improved the water status in stressed seedlings and thereby physiological and biochemical parameters and thus ameliorated the severe effects of water stress, which significantly decreased the RWC, growth and dry mass of non-inoculated seedlings.
Abstract: The sunflower (Helianthus annuus L. cv. PAC 36) seedlings were inoculated with plant growth promoting rhizobacteria (PGPR), viz. Azotobacter chroococcum (A+), Bacillus polymyxa (B+), separately and in combination of the two (AB+). Relative water content and seedling growth were maximum in AB+ seedlings under control. Water stress significantly decreased the RWC, growth and dry mass of non-inoculated seedlings. However, inoculated seedlings maintained higher growth even under water stress. Pigments and protein contents decreased under water stress, but higher amount of the same was observed in stressed AB+ seedlings. Enhanced activity of nitrate reductase was recorded in AB+ seedlings with maximum in control. Water stress significantly decreased the nitrate reductase activity. A significant increase in the activity of superoxide dismutase (SOD) in leaves was recorded under water stress except in B+ with maximum increase in non-inoculated seedlings. Catalase (CAT) activity decreased in stressed non-inoculated seedlings while increased in the leaves of A+ and AB+ seedlings. Almost similar trends were recorded for both leaves and cotyledons. PGPR improved the water status in stressed seedlings and thereby physiological and biochemical parameters and thus ameliorated the severe effects of water stress.
35 citations
TL;DR: Experiments indicate harmful allelopathic effects of Jatropha leachates /extracts on wheat seedlings, hence further experimentation and analysis is recommended before continued plantation of Jandropha particularly on fertile soils.
Abstract: Jatropha curcas shows invasive characters and is a significant source of many phytochemicals with varying biological activities. Different plant parts of Jatropha curcas L exhibited variation in their phytochemical constituents. Leaves and ovary walls were found to contain higher contents of total phenols, tannins and phytic acid whereas free amino acids were greater in leaves. Young leaves of Jatropha show greater contents of all these metabolites. Further, plants exhibit seasonal differences as leaves collected during summer (May-June) have greater accumulation of total phenols, tannins and free amino acids however, phytic acid was more during rainy season. Leachates and extracts in their higher concentrations adversely affected the germination and growth of wheat seedlings however, lower concentrations were more or less stimulatory. These treatments not only decreased the length, fresh and dry weight of seedlings but also affected the chlorophyll contents and activity of enzymes such as nitrate reductase, aminotransferases in wheat seedlings however, the activity of superoxide dismutase and ascorbate peroxidases increased. Experiments indicate harmful allelopathic effects of Jatropha leachates /extracts on wheat seedlings, hence further experimentation and analysis is recommended before continued plantation of Jatropha particularly on fertile soils. However. Growth of Jatropha plants on saline soils and their potential for accumulating sodium, potassium and chloride are the attributes suggesting the possibility of use of Jatropha plants in improving saline soils.
TL;DR: The lines of evidence presented here reveal the suppressive influence of the three growth hormones studied on fungal development and are important to encourage further and more in-depth examinations of this intriguing hormonal complex regulatory and its role in the maize-H.
Abstract: Late wilt, a severe vascular disease of maize caused by the fungus Harpophora maydis, is characterized by rapid wilting of maize plants before tasseling and until shortly before maturity. The pathogen is currently controlled by resistant maize cultivars, but the disease is constantly spreading to new areas. The plant’s late phenological stage at which the disease appears suggests that plant hormones may be involved in the pathogenesis. This work revealed that plant growth hormones, auxin (Indole-3-acetic acid) and cytokinin (kinetin), suppress H. maydis in culture media and in a detached root assay. Kinetin, and even more auxin, caused significant suppression of fungus spore germination. Gibberellic acid did not alter colony growth rate but had a signal suppressive effect on the pathogens’ spore germination. In comparison, ethylene and jasmonic acid, plant senescing and defense response regulators, had minor effects on colony growth and spore germination rate. Their associate hormone, salicylic acid, had a moderate suppressive effect on spore germination and colony growth rate, and a strong influence when combined with auxin. Despite the anti-fungal auxin success in vitro, field experiments with dimethylamine salt of 2,4-dichlorophenoxyacetic acid (that mimics the influence of auxin) failed to suppress the late wilt. The lines of evidence presented here reveal the suppressive influence of the three growth hormones studied on fungal development and are important to encourage further and more in-depth examinations of this intriguing hormonal complex regulatory and its role in the maize-H. maydis interactions.
TL;DR: This optimized regeneration protocol can be efficiently used for genetic transformation in broccoli and is the first comparative report on multiple shoot induction using four different types of explants viz. hypocotyl, cotyledon, leaf and petiole.
Abstract: Broccoli (Brassica oleracea L. var. italica) is an important, nutritionally rich vegetable crop, but severely affected by environmental stresses, pests and diseases which cause massive yield and quality losses. Genetic manipulation is becoming an important method for broccoli improvement. In the present study, a reproducible and highly efficient protocol for obtaining organogenesis from hypocotyl, cotyledon, leaf and petiole explants of broccoli (Brassica oleracea L. var. italica cv. Solan green head) has been developed. Hypocotyl and cotyledon explants were used from 10 to 12 days old aseptically grown seedlings whereas leaf and petiole explants were excised from 18 to 20 days old green house grown seedlings and surface sterilized. These explants were cultured on shoot induction medium containing different concentration and combination of BAP and NAA. High efficiency shoot regeneration has been achieved in hypocotyl (83.33 %), cotyledon (90.11 %), leaf (62.96 %) and petiole (91.10 %) explants on MS medium supplemented with 3.5 mg/l BAP + 0.019 mg/l NAA 2.5 mg/l BAP + 0.5 mg/l NAA, 4.0 mg/l BAP + 0.5 mg/l NAA and 4.5 mg/l BAP + 0.019 mg/l NAA respectively. Petiole explants showed maximum shoot regeneration response as compared to other explants. MS medium supplemented with 0.10 mg/l NAA was found best for root regeneration (100 %) from in vitro developed shoots. The regenerated complete plantlets were transferred to the pots containing cocopeat and successfully acclimatized. This optimized regeneration protocol can be efficiently used for genetic transformation in broccoli. This is the first comparative report on multiple shoot induction using four different types of explants viz. hypocotyl, cotyledon, leaf and petiole.
TL;DR: The different nutritional parameters were also found to be in variable concentration among different germplasms viz. total soluble protein, free amino acids, starch, reducing and non reducing sugar, total soluble sugar and antinutritional parameters.
Abstract: Eleven germplasms of faba bean seeds from four agroclimatic regions of Bihar, India, have been investigated to estimate their nutritional (soluble protein, free amino acids, starch, reducing and non reducing sugar, total soluble sugar) and antinutritional (total extractable phenol and condensed tannin/proanthocyanidin) parameters. These parameters were found in varying concentration in all genotypes studied. The highest concentration of total extractable phenol and proanthocyanidin (condensed tannin) (2.56 and 1.59 % leucocyanidin equivalents respectively on dry matter basis) were found in Samastipur while the lowest from Patna (0.95 and 0.426 % leucocyanidin equivalent on dry matter basis). The different nutritional parameters were also found to be in variable concentration among different germplasms viz. total soluble protein ≈ 20–32 %, free amino acids ≈ 188–348 mg/100 g, starch ≈ 27–33 %, reducing sugars ≈ 85–188 mg/100 g, non reducing sugars ≈ 0.7–1.7 % and total soluble sugars ≈ 0.8–1.9 %.
TL;DR: The results suggest thatchlorophyll content and chlorophyll fluorescence may be used as a secondary character for screening heat-tolerant genotypes.
Abstract: Field experiments for evaluating heat tolerance- related physiological traits were conducted for two consecutive years using a mapping population of recombinant inbred lines (RILs) from the cross RAJ4014/WH730. Chlorophyll content (Chl) and chlorophyll fluorescence (CFL) were recorded under timely sown (TS) and late sown (LS) conditions. Late sowing exposes the terminal stage of pla nts to high temperature stress. Pooled analysis showed that CFL and Chl differed significantly under TS and LS conditions. The mean value of CFL (Fv/Fm) and Chl under both timely and late sown conditions were used as physiological traits for association with markers. Regression analysis revealed significant association of microsatellite markers viz., Xpsp3094 and Xgwm131 with coefficients of determination (R 2 ) values for CFL (Fv/Fm) and Chl as 12 and 8 %, respectively. The correlation between thousand grain weight (TGW) with Chl and CFL were 14 and 7 % and correlation between grain wt./spike with Chl and CFL were 15 and 8 %, respectively. The genotypes showing tolerance to terminal heat stress as manifested by low heat susceptibility index (HSI=0.43) for thousand grain weight, were also found having very low Chl, HSI (−0.52). These results suggest that these physiological traits may be used as a secondary character for screening heat-tolerant genotypes.
TL;DR: An efficient and reproducible in vitro propagation protocol has been established for Cadaba fruticosa (L.) Druce and can be applied for commercial cultivation, which may be important for extraction of bioactive compounds and may facilitate conservation of this multipurpose endangered medicinal shrub.
Abstract: An efficient and reproducible in vitro propagation protocol has been established for Cadaba fruticosa (L.) Druce. Surface-sterilized nodal stem segments of mature plant were used as explants for culture establishment. Multiple shoots were optimally differentiated from the nodal stem explants through bud breaking on Murashige and Skoog (1962) medium containing 3.0 mg l−1 benzyladenine (BA). The effect of different plant growth regulators and minerals were studied on different stages of micropropagation procedure (i.e., explant establishment, shoot multiplication/growth and ex vitro rooting). Additionally, for enhancing shoot multiplication during subculture, MS medium was modified (MMS) with higher levels of magnesium, potassium and sulphate ions. Out of these, MMS3 medium containing 0.25 mg l−1 each of BA and Kin (N6-furfuryladenine), with 0.1 mg l−1 NAA (α-naphthalene acetic acid) was found the best for shoot multiplication (42.45 ± 3.82 per culture vessel). The in vitro regenerated shoots were rooted under ex vitro conditions on treating the shoot base with 500 mg l−1 of IBA (indole-3 butyric acid) for 3 min on sterile Soilrite®. The ex vitro rooted plants were hardened in the greenhouse and transferred to the field with ≈85 % survival rate. There were not any visual differences between wild and micropropagated plants in the field, although the later underwent significant changes during acclimatization. Micromorphological changes on leaf surface characters from in vitro to acclimatized plantlets were studied in terms of development of glandular trichomes, changes in vein spacing and vein structure in order to understand the nature of plant responses towards environmental conditions. The method developed and defined can be applied for commercial cultivation, which may be important for extraction of bioactive compounds and may facilitate conservation of this multipurpose endangered medicinal shrub.
TL;DR: The majority of genotypes including four improved cultivars were grouped in a single subcluster IIIa of cluster III, indicating high genetic resemblance among soybean germplasm collection in India.
Abstract: Molecular characterization and genetic diversity among 82 soybean accessions was carried out by using 44 simple sequence repeat (SSR) markers. Of the 44 SSR markers used, 40 markers were found polymorphic among 82 soybean accessions. These 40 polymorphic markers produced a total of 119 alleles, of which five were unique alleles and four alleles were rare. The allele number for each SSR locus varied between two to four with an average of 2.97 alleles per marker. Polymorphic information content values of SSRs ranged from 0.101 to 0.742 with an average of 0.477. Jaccard's similarity coefficient was employed to study the molecular diversity of 82 soybean accessions. The pairwise genetic similarity among 82 soybean accessions varied from 0.28 to 0.90. The dendrogram constructed based on genetic similarities among 82 soybean accessions identified three major clusters. The majority of genotypes including four improved cultivars were grouped in a single subcluster IIIa of cluster III, indicating high genetic resemblance among soybean germplasm collection in India.
TL;DR: DAMD and ISSR profiling have identified diverse turmeric genotypes, which could be further utilized in various genetic improvement programmes including conventional as well as marker assisted breeding towards development of new and desirable turmericgenotypes.
Abstract: Curcuma longa L., commonly known as turmeric, is one of the economically and medicinally important plant species. It is predominantly cultivated in the tropical and sub tropical countries. India is the largest producer, and exporter of turmeric in the world, followed by China, Indonesia, Bangladesh and Thailand. In the present study, Directed Amplification of Minisatellite DNA (DAMD) and Inter Simple Sequence Repeats (ISSR), methods were used to estimate the genetic variability in indigenous turmeric germplasm. Cumulative data analysis for DAMD (15) and ISSR (13) markers resulted into 478 fragments, out of which 392 fragments were polymorphic, revealing 82 % polymorphism across the turmeric genotypes. Wide range of pairwise genetic distances (0.03–0.59) across the genotypes revealed that these genotypes are genetically quite diverse. The UPGMA dendrogram generated using cumulative data showed significant relationships amongst the genotypes. All 29 genotypes studied grouped into two clusters irrespective of their geographical affiliations with 100 % bootstrap value except few genotypes, suggesting considerable diversity amongst the genotypes. These results suggested that the current collection of turmeric genotypes preserve the vast majority of natural variations. The results further demonstrate the efficiency and reliability of DAMD and ISSR markers in determining the genetic diversity and relationships among the indigenous turmeric germplasm. DAMD and ISSR profiling have identified diverse turmeric genotypes, which could be further utilized in various genetic improvement programmes including conventional as well as marker assisted breeding towards development of new and desirable turmeric genotypes.
TL;DR: An ultra-performance liquid-chromatography in combination with electrospray ionization tandem mass spectrometry involving metal cationisation was successfully utilized for the rapid identification of xanthone and secoiridoid glycosides.
Abstract: A rapid analytical method has been developed to determine xanthone and secoiridoid glycoside in in vitro and in vivo Swertia chirayita extracts. Ultra performance liquid chromatography–electrospray ionization mass spectrometry (LC-ESI/MS) was applied and validated for the analysis of xanthone and secoiridoid glycoside a potential active component isolated from methanolic extracts of in vitro and in vivo Swertia chirayita plantlets. Chromatographic separation was achieved on a RP-C18 column using gradient elution. Mangiferin (Xanthone), Amarogentin and Swertiamarin (Secoiridoid glycosides) were identified in both the extracts. In the LC/ESI-MS spectra, major [M + H] + and [M + Na] + ions were observed in positive ion mode and provided molecular mass information. An ultra-performance liquid-chromatography in combination with electrospray ionization tandem mass spectrometry involving metal cationisation was successfully utilized for the rapid identification of xanthone and secoiridoid glycosides. This method is suitable for the routine analysis, as well as for the separation and identification of known and novel secoiridoid glycoside and xanthone.
TL;DR: It seems from foregoing study that tripartite combination of different micro-organisms can be explored as biofertilizer for improvement in chickpea productivity.
Abstract: Chickpea establishes symbiotic association with Mesorhizobium to fulfill its nitrogen (N) requirement. Integrating chickpea rhizosphere with potential native mesorhizobia and other plant growth promoting microorganisms can contribute multiple benefits to plants. The present investigation was undertaken to study interactions among Piriformospora indica (PI) with potential plant growth promoting rhizobacteria (PGPR) viz. Pseudomonas argentinensis (LPGPR1), Pseudomonas sp. (LPGPR2) along with national check Pseudomons sp. (LK884) and Mesorhizobium cicer (LGR33, MR) to examine the synergistic effect of consortium for improving growth, symbiotic efficiency, nutrient acquisition and yield in two chickpea (Cicer arietinum L.) varieties viz. desi PBG1 and kabuli BG1053. In-vitro, seed germination with consortium MR + PI + LPGPR1 was the best compatible treatment followed by MR + PI + LK884 and MR + PI + LPGPR2. Significant improvement in the growth, symbiotic parameters and grain yield was observed with MR + PI + LPGPR1 and MR + PI + LK884 treatments. Significantly high chlorophyll and leghaemoglobin content was recorded with MR + PI + LPGPR1 (1.57 and 1.64 mg g−1 fresh weight of leaves and 5.19 and 4.39 mg/g−1 fresh weight of nodules) in desi PBG1 and kabuli BG1053 chickpea varieties, respectively. At 90 DAS, MR + PI + LPGPR1 treatment significantly improved nodule dry weight (ranged between 84.0 and 141.7 mg plant−1) as compared to MR alone treatment (ranged between 62.3 and 123.3 mg plant−1). Data revealed significant increase in total nitrogen (N) and phosphorus (P) content of shoot with MR + PI + LPGPR1 by 1.2 and 1.5 fold, respectively over MR alone treatment. On the basis of overall mean, MR + PI + LPGPR1 significantly improved the yield by 8.2 % over Mesorhizobium alone application. It seems from foregoing study that tripartite combination of different micro-organisms can be explored as biofertilizer for improvement in chickpea productivity.
TL;DR: A differential link between mdar gene expression and enzyme activity under oxidative stress that is validated under different types of imposed stresses is established and Alteration in correlation between geneexpression and enzyme activities under varying magnitude of oxidative stress is elucidated.
Abstract: Abiotic stresses constitute a serious threats to the world food security as they cause significant economic losses in terms of reduction in crop productivity and also greatly limit the geographical locations where crops can be grown. Exposure to abiotic stress causes over-production of reactive oxygen species, leading to oxidative stress in plants. Induction of oxidative stress is primarily responsible for a variety of detrimental changes in the cellular physiology. However, plants have evolved intricate anti-oxidative defence machinery, for their survival under stress. Plant defence strategies for stress tolerance rely on the expression of anti-oxidative genes required for scavenging the toxic reactive oxygen species. Monodehydroascorbate reductase is one of the key anti-oxidant enzyme responsible for scavenging reactive oxygen species. In the present study, efforts have been made to understand the role of monodehydroascorbate reductase in finger millet under different abiotic stresses (drought, salt and UV radiation). The study establishes a differential link between mdar gene expression and enzyme activity under oxidative stress that is validated under different types of imposed stresses. Alteration in correlation between gene expression and enzyme activities under varying magnitude of oxidative stress is elucidated.
TL;DR: Since the isolated RNA passed highly stringent quality control standards for sensitive reactions, including RNA sequencing and real-time PCR, it can be considered as a reliable and cost-effective method for RNA extraction from woody plants.
Abstract: The quality and quantity of RNA are critical for successful downstream transcriptome-based studies such as microarrays and RNA sequencing (RNA-Seq). RNA isolation from woody plants, such as Pistacia vera, with very high amounts of polyphenols and polysaccharides is an enormous challenge. Here, we describe a highly efficient protocol that overcomes the limitations posed by poor quality and low yield of isolated RNA from pistachio and various recalcitrant woody plants. The key factors that resulted in a yield of 150 μg of high quality RNA per 200 mg of plant tissue include the elimination of phenol from the extraction buffer, raising the concentration of β-mercaptoethanol, long time incubation at 65 °C, and nucleic acid precipitation with optimized volume of NaCl and isopropyl alcohol. Also, the A260/A280 and A260/A230 of extracted RNA were about 1.9–2.1and 2.2–2.3, respectively, revealing the high purity. Since the isolated RNA passed highly stringent quality control standards for sensitive reactions, including RNA sequencing and real-time PCR, it can be considered as a reliable and cost-effective method for RNA extraction from woody plants.
TL;DR: Biochemical responses of Ocimum tenuiflorum plants were studied upon exposure to arsenite (AsIII) and arsenate (AsV) for 1 to 10 d, finding that plants tolerated high As concentrations through induced antioxidant machinery.
Abstract: Biochemical responses of Ocimum tenuiflorum plants were studied upon exposure to arsenite (AsIII) and arsenate (AsV) for 1 to 10 d. Plants accumulated significant amounts of As in leaves (662 μg g−1 dry weight; DW and 412 μg g−1 DW in response to 100 μM AsIII and AsV exposure, respectively after 10 d). Consequently, fresh weight and growth of plants declined in a concentration dependent manner. Further, total chlorophyll and carotenoid contents also declined while oxidative stress markers increased, particularly on longer durations. Various antioxidant enzymes and thiols (cysteine and glutathione; GSH) showed significant and variable increases upon exposure to AsV and AsIII with the response being comparatively better in response to AsV. Proline increased significantly upon exposure to both AsIII and AsV. Plants thus tolerated high As concentrations through induced antioxidant machinery.
TL;DR: A high level of genetic diversity was found among 48 individuals and it will be possible to exploit the available resources of okra in more valuable ways.
Abstract: Okra is a widely distributed crop in the tropics, subtropics, and warmer areas of the temperate zones. Its major potential uses as a vegetable, oil and protein source, and source of paper pulp and fuel, or biomass are compatible. It is expected to have high value of exploitation and application. Due to the limited number of molecular studies focused on okras, the methods of morphological and ISSR markers were used to analysis the genetic diversity of 48 okras in the present study. The 22 primers were picked for ISSR-PCR, and a total of 154 fragments were amplified with an overall average polymorphism of 54.55 %. We used the 154 markers to construct the dendrogram based on the unweighted pair group method with arithmetic means (UPGMA). A high level of genetic diversity was found among 48 individuals. The 48 Okras was divided into four clusters at Dice’s coefficient of 0.19 with clustering analysis. Based on these data of the genetic diversity, it will be possible to exploit the available resources of okra in more valuable ways.
TL;DR: A complex and multi-level regulatory system modulating response to drought stress in B. napus plants is suggested, supported by the involvement of a post-transcriptional level of regulation for B.Napus drought response.
Abstract: It is of great significance to understand the regulatory mechanisms by which plants deal with drought stress. Two EST libraries derived from rapeseed (Brassica napus) leaves in non-stressed and drought stress conditions were analyzed in order to obtain the transcriptomic landscape of drought-exposed B. napus plants, and also to identify and characterize significant drought responsive regulatory genes and microRNAs. The functional ontology analysis revealed a substantial shift in the B. napus transcriptome to govern cellular drought responsiveness via different stress-activated mechanisms. The activity of transcription factor and protein kinase modules generally increased in response to drought stress. The 26 regulatory genes consisting of 17 transcription factor genes, eight protein kinase genes and one protein phosphatase gene were identified showing significant alterations in their expressions in response to drought stress. We also found the six microRNAs which were differentially expressed during drought stress supporting the involvement of a post-transcriptional level of regulation for B. napus drought response. The drought responsive regulatory network shed light on the significance of some regulatory components involved in biosynthesis and signaling of various plant hormones (abscisic acid, auxin and brassinosteroids), ubiquitin proteasome system, and signaling through Reactive Oxygen Species (ROS). Our findings suggested a complex and multi-level regulatory system modulating response to drought stress in B. napus.
TL;DR: Higher degree of polymorphism as revealed from UPGMA Dendrogram and Nei’s genetic diversity might be attributed towards the comfortable growth of B. gymnorrhiza and H. fomes and towards their precarious status in present days elevated salinity in Indian Sundarbans.
Abstract: Increased salinity distresses some key species severely in Indian Sundarbans. Geomorphic characteristics coupled with demographic obligations have proven to be pivotal factor towards the prevalence of elevated salinity in this zone. Better adaptation to rapid changes in microclimate demands wide range of genetic polymorphism as well. RAPD and ISSR molecular markers were used for this genetic diversity study. Degree of polymorphism was found relatively higher in Bruguiera gymnorrhiza (26.43 % in RAPD and 24.36 % in ISSR) than the other taxa, Heritiera fomes (14.43 and 12.76 % respectively) in case of RAPD and ISSR. Dendrogram constructed based on the similarity matrix showed that for H. fomes, least saline and highest saline zones are positioned in the same clade; whereas in B. gymnorrhiza the higher saline areas were clustered together. Nei’s gene diversity (h) as revealed from RAPD and ISSR analysis were found to be 0.0821, 0.0785 and 0.0647, 0.0592 in B. gymnorrhiza and H. fomes respectively. The higher degree of polymorphism as revealed from UPGMA Dendrogram and Nei’s genetic diversity might be attributed towards the comfortable growth of B. gymnorrhiza all along the Indian Sundarbans. On the other hand the relatively lesser degree of genetic polymorphism of H. fomes might be attributed towards their precarious status in present days elevated salinity in Indian Sundarbans.
TL;DR: Gathered data demonstrated that increased drying lowers the critical water content for tissue survival and also reduces the risk of damage resulting from aqueous-based deleterious reactions and showed that growing radicles are a popular model to explore desiccation-sensitivity in plant tissues and/or seeds.
Abstract: Orthodox seed serves as easily accessible model to study desiccation-sensitivity in plant tissues because once they undergo germination, they become sensitive to desiccation imposed injuries. In the proposed study, effects of rate of drying on the viability, electrolyte leakage, superoxide accumulation, lipid-protein oxidation and antioxidant enzymes were explored in excised radicles of Cicer arietinum L. under dehydration and wet storage. For both the drying conditions, desiccation could be explained by exponential and inverse functions. Under rapid drying tissue viability as scored by germination efficiency and tetrazolium staining remained 100 % all through the analysis (24 h) but declined remarkably after 0.30 g g−1 fresh mass water content (4 days) under slow drying. Moreover, precipitous fall in tissue viability was observed after 2 weeks of wet storage. Rapid drying was also accompanied with limited amounts of electrolyte leakage, superoxide radical, malondialdehyde and protein hydroperoxide, together with enhanced level of protein. Additionally, activities of both superoxide dismutase and ascorbate peroxidase were increased in rapidly dried radicles, but guaiacol peroxidase was declined. In contrary, above referred biomarkers were observed to perform either inversely or poorly during slow drying and wet storage suggesting that above documented alterations might be the resultant of ageing and not desiccation. Gathered data demonstrated that increased drying lowers the critical water content for tissue survival and also reduces the risk of damage resulting from aqueous-based deleterious reactions. Additionally, it also showed that growing radicles are a popular model to explore desiccation-sensitivity in plant tissues and/or seeds.
TL;DR: It is suggested that genes functioning in many physiological events coordinate the response to availability of nitrogen and also for the improvement of NUE of crops.
Abstract: Inorganic nitrogen (N) is a key limiting factor of the agricultural productivity. Nitrogen utilization efficiency has significant impact on crop growth and yield as well as on the reduction in production cost. The excessive nitrogen application is accompanied with severe negative impact on environment. Thus to reduce the environmental contamination, improving NUE is need of an hour. In our study we have deployed comparative proteome analysis using 2-DE to investigate the effect of the nitrogen nutrition on differential expression pattern of leaf proteins in low-N sensitive and low-N tolerant wheat (Triticum aestivum L.) varieties. Results showed a comprehensive picture of the post-transcriptional response to different nitrogen regimes administered which would be expected to serve as a basic platform for further characterization of gene function and regulation. We detected proteins related to photosynthesis, glycolysis, nitrogen metabolism, sulphur metabolism and defence. Our results provide new insights towards the altered protein pattern in response to N stress. Through this study we suggest that genes functioning in many physiological events coordinate the response to availability of nitrogen and also for the improvement of NUE of crops.
TL;DR: GC-MS analysis of methanolic extracts have revealed the presence of compounds viz. n-Hexadecanoic acid, N-Methoxy-N-methylacetamide, Ursa-9(11), 12-dien-3-ol, Gamma-sitosterol etc., that might be potential candidates for the biological activity exhibited by the extract.
Abstract: Salacia oblonga, an inhabitant of tropical regions has been used in traditional Indian medicinal systems Phytochemicals were extracted in methanol from the plant and analyzed for various biological activities The results of biochemical tests for total phenolics (297 ± 0005 and 275 ± 0006) and flavonoids (95 ± 0004 and 616 ± 0004) in the aerial and root parts were indicated as Gallic acid and quercetin equivalents respectively The Aerial and root extracts showed strong reducing ability based on reducing power and FRAP assays The extracts exhibited significant IC50 values in DPPH, super oxide and nitric oxide radical scavenging assays The extracts displayed low IC50 values (<50 μg/ml) when assessed for antiproliferative activity against breast cancer cell lines using the MTT assay GC-MS analysis of methanolic extracts have revealed the presence of compounds viz n-Hexadecanoic acid, N-Methoxy-N-methylacetamide, Ursa-9(11), 12-dien-3-ol, Gamma-sitosterol etc, that might be potential candidates for the biological activity exhibited by the extract
TL;DR: Drought induced changes in gene expression in two contrasting genotypes were consistent with the physiological response and Expression of hsp gene was found to be upregulated during drought stress.
Abstract: Brassica juncea is an important oilseed crop and drought stress is major abiotic stress that limits its growth and productivity. RH0116 (drought tolerant) and RH8812 (drought sensitive) genotypes were undertaken to study some of the physiological parameters and hsp gene expression related to stress tolerance under drought stress conditions. Differential response in terms of seed germination, electrolyte leakage, RWC, osmotic potential was observed in the selected genotypes. In vitro seed germination studies using PEG stress treatments indicated reduced seed germination with increasing levels of stress treatment. Electrolyte leakage increased, whereas, relative water content and osmotic potential decreased in stressed seedlings. Expression of hsp gene was found to be upregulated during drought stress as the transcripts were present only in the stressed plants and disappeared upon rehydration. The drought tolerant variety showed higher transcript accumulation as compared to the sensitive variety. The study showed that drought induced changes in gene expression in two contrasting genotypes were consistent with the physiological response.