Browsing by Author "S.K. Verma"

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Assessment of Bioactive Potential and Characterization of an Anticancer Compound from the Endophytic Fungi of Ocimum sanctum
(Pleiades Publishing, 2024) A. Verma; K. Kumar; U. Talukdar; G. Pal; D. Kumar; P. Shukla; S. Patel; A. Kumar; A. Kumar; R.N. Kharwar; S.K. Verma
Abstract: The goal of this study was to isolate endophytic fungi from Ocimum sanctum L. and to evaluate their biological potential, including antibacterial, antioxidant, and enzymatic activities and further characterization of the bioactive compounds. Nine endophytic fungi were isolated from the leaves and stem tissues of O. sanctum collected from the botanical garden of Banaras Hindu University, Varanasi, India. All isolates were identified based on their microscopic structures and molecular sequencing of the ITS rDNA. Aspergillus clavatonanicus (SS7) and Cochliobolus hawaiiensis (SL3) showed the highest colonization frequencies in the stem and leaves (16 and 14%, respectively). All fungal isolates were tested for extracellular enzymatic activities of amylase, cellulase, and pectinase. Of the nine fungal isolates, 60% tested positive for amylase and cellulase, whereas 50% showed pectinase activity. Using a disc diffusion assay, the extracted secondary metabolites were checked for antibacterial activity against three human pathogenic bacteria. Two isolates, SL2 and SS7, exhibited the highest antibacterial activity against all pathogens, including Enterococcus faecalis, Klebsiella pneumoniae, and methicillin-resistant Staphylococcus aureus (MRSA). Crude extracts of the six fungal isolates showed positive antioxidant activity. The crude extract of Aspergillus allahabadii (isolate SL2) showed strong antibacterial and antioxidant activities and crystallized during purification. X-ray crystallography confirmed the identity of the crystal as citrinin, which also exhibited strong anticancer activity against Dalton’s lymphoma cells. The results of this study suggest that endophytic fungi isolated from the leaf and stem tissues of Ocimum sanctum are potential sources of antibacterial, antioxidant, and anticancer compounds. © Pleiades Publishing, Ltd. 2024. ISSN 0026-2617, Microbiology, 2024, Vol. 93, No. 4, pp. 459–471. Pleiades Publishing, Ltd., 2024.
Bio-efficacy and selectivity of sulfosulfuron and metribuzin before and after irrigation in wheat (Triticum aestivum) under zero-tillage system
(2009) R.K. Singh; S.K. Verma; Rajvir Sharma; S.B. Singh
A field experiment was conducted during winter(rabi) season of 2003-04 and 2004-05 at agronomy reasearch farm, BHU, Varanasi, to study the bio-efficacy and selectivity of sulfosulfuron and metribuzin before and after irrigation in wheat (Triticum aestivum L. emend. Fiori & Paol.) underzerotillage system. Eight ween control treatments, viz metribuzin 0.21 kg/ha before first irrigation (BFI), Metribuzin 0.21 kg/ha after first irrigation (AFI), sulfosulfuron 0.025 kg/ha BFI sulfosulfuron 0.025 kg/ha AFI, isoproturon +2, 4-D0.75+0.5 kg/ha AFI, 1 hand weeding at 30 days after sowing (DAS), 2 were tested in randomized block design with 3 replications. Sulfosulfuron (AFI) significantly reduced weed density, dry weight and NPK depletion by weeds with maximum weed control efficiency (79.4%) and improved the NPK uptake by crop which cause significant impact on crop growth and yield attributes which resulted higher grain yield (3.24 and 3.53 tonnes/ha), being at par with that of one hand weeding at 30 days after sowing. Isoproturon + 2, 4-D (AFI) significantly reduced density and dry weight of weeds over metribuzin (BFI) and sulfosulfuron (BFI) and it was at par with metribuzin (AFI) and 1 hand weeding. Among the herbicidal treatments, maximum net returns (Rs 7564 and 9165/ha) and benefit: cost ration (1.54 and 1.63) were recorded under isoproturon + 2, 4-D (AFI). Hand weeding twice at 30 and 45 DAS recorded significantly higher yield attributes, grain yield, nutrients uptake with maximum weed control efficiency, net returns and benefits : cost ration over all other weed control treatments.
Bioassay studies for bruchid (Callosobruchus chinensis) resistance in F7 inter-specific generation of pigeonpea (Cajanus cajan)
(2012) Jaggal Somappa; Naseer Mohammad; G.C. Bajpai; S.K. Verma; Reena Joshi
The results of bioassay indicated that per cent adult emergence, mean time of adult emergence and per cent weight loss were most important parameters which helped in categorizing the genotypes into susceptible or resistant. Out of nine interspecific progenies, one of progeny UPAS120 × C. scarabaeiodes was found least susceptible for Callosobruchus chinensis, while other progenies in the descending order for resistance to bruchid were UPAS120 × C. cajanifolius, PA134 × C. scarabaeiodes, PA134 × C. acutifolius, ICPL84023 × C. cajanifolius and ICPL84023 × C. scarabaeiodes. Since genetic resistance is the cheapest source of resistance in managing the biotic stress, the resistant material found in this study will definitely useful in the pigeonpea improvement programme especially for bruchid resistance.
Biochemical markers of environmental stress tolerance in finger millet [Eleusine coracana (L.) Gaertn.] germplasm of Central Himalayan Region
(Springer Science and Business Media B.V., 2022) A.K. Trivedi; S.K. Verma; R.K. Tyagi; A. Hemantaranjan; Achal Singh
Availability of the germplasm of suitable crops for cultivation in environmental stress prone and resource poor terrains is crucial for food security in these regions. Rich diversity of millets, which are highly tolerant to extreme weather conditions, is obtainable in the Central Himalayan Region (CHR). However, biochemical evaluation of available germplasm for food security is a major apprehension yet to be addressed properly. In this backdrop expeditions were conducted to tap and evaluate the germplasm variability of finger millet [Eleusine coracana (L.) Gaertn.]. Germplasm accessions (314) having traits of agronomic importance were collected and evaluated for three consecutive years. In addition to set of biochemical traits, yield was recorded to find out suitable germplasm for large scale cultivation/breeding programme. At flowering stage variability in antioxidants level of leaves such as glutathione and ascorbate ranged from 105.27 to 423.63 mmol g−1 FW and 4.89–10.21 mmol g−1 FW respectively. Extensive variableness in the activity of enzymes which are important for multiple abiotic stress tolerance viz., catalase (115–855 mmol H2O2 decomposed min−1 mg−1 protein), peroxidase (1.24–6.35 mmol substrate min−1 mg−1 protein), superoxide dismutase (1236–2963 enzyme U mg−1 protein), glutathione reductase (0.53–2.14 mmol substrate min−1 mg−1 protein), ascorbate peroxidase (1.86–7.04 mmol substrate min−1 mg−1 protein), monodehydroascorbate reducatase (1.11–4.41 mmol substrate min−1 mg−1 protein), dehydroascorbate reducatase (0.34–1.36 mmol substrate min−1 mg−1 protein) was also recorded. Worldwide Abiotic/environmental stresses hamper agricultural production. Enzymatic and non-enzymatic defence system precisely controls this situation. Hence, biochemical evaluation might be an appropriate strategy for identification of suitable germplam to combat the problem of food security in such areas. © 2022, The Author(s), under exclusive licence to Springer Nature B.V.
Characterization of Soils of Narasinghpur Block in Cuttack District of Odisha
(Indian journals, 2023) Lilan Kumar Behera; Ramawatar Meena; Pragnya Paramita Patel; S.K. Verma
This experiment was carried out to characterize the soils of the study area through the profile study in Cuttack district of Odisha state. In this experiment 15 villages were selected for the profile study. Four samples were collected from each profile from four depths (0-15, 15-30, 30-60 and 60-90 cm). Depth-wise soil samples were processed and analysed for soil texture, bulk density, particle density, porosity, soil pH, electrical conductivity (EC), organic carbon (OC), available nitrogen (N), phosphorus (P), potassium (K), sulphur (S), iron (Fe), zinc (Zn) copper (Cu) and manganese (Mn). Results of soil analysis revealed that soil texture of the studied area was sandy loam and sandy clay loam. Bulk density increased with the increasing depth of the profile and found in the range between 1.23 to 1.45 Mg m-3. The pH values of the soils of the studied area were neutral to slightly alkaline and EC was <1 dS m-1. The average OC of the surface soil was slightly medium, which reduced with the increasing depth of the profile. Nitrogen content of the studied area was in the medium range and decreased in the soil profile up to 90 cm depth. Phosphorus content was in the medium range and K content was in high range and both decreased in the soil profile with the increasing depth. Soils of the study area were deficient in S content. Micronutrients (Fe, Zn, Cu and Mn) were slightly higher than the critical limits and reduced gradually along with the depth of soil profile. © 2023, Indian journals. All rights reserved.
Copper toxicity and phosphate utilization in the cyanobacterium Nostoc calcicola
(1993) S.K. Verma; R.K. Singh; S.P. Singh
[No abstract available]
Copper uptake by free and immobilized cyanobacterium
(1989) S.P. Singh; S.K. Verma; R.K. Singh; P.K. Pandey
Copper uptake in free and immobilized cells of the cyanobacterium Nostoc calcicola has been examined. The immobilized cells invariably maintained a higher profile of Cu intake rate (12.7 nmol mg-1 protein min-1) over the free cells (6.0 nmol mg-1 protein min-1). The total Cu uptake in immobilized cells was almost two and a half-times more than their free cell counterpart under identical experimental conditions. Also, the immobilized cells showed a stronger positive correlation between Cu adsorption and uptake. The results have been discussed in terms of improved metabolic efficiency of immobilized cells. © 1989.
Diversity and biopotential of endophytic fungal flora isolated from eight medicinal plants of Uttar Pradesh, India
(Springer India, 2014) R.N. Kharwar; Ashish Mishra; Vijay K. Sharma; S.K. Gond; S.K. Verma; A. Kumar; Jitendra Kumar; D.K. Singh; J. Goutam
Endophytic fungi are hidden diversity mines of microbes that reside in the healthy and symptomless interior of plant tissues without causing any harmful effects. This chapter focuses on fungal endophytic diversity of eight medicinal plants of Uttar Pradesh, India with their biopotential ability. Total of 4,002 (38.38 % CF) endophytic isolates were recovered from 10,425 segments representing 131 endophytic fungal species belonging to different fungal classes. Out of 4,002 isolates, hyphomycetes were more pronounced with 71.43 % recovery followed by coelomycetes 16.61 %, ascomycetes 6.59 %, mycelia sterilia or unidentified 5.32 % and least from zygomycetes 0.020 %. Among total endophytic fungal species isolated, Cladosporium cladosporioides (3.39 % CF) was found to be the most dominated taxa followed by Alternaria alternata (2.35 % CF), Curvularia lunata (2.13 % CF), Aspergillus niger (1.95 % CF), Chaetomium globosum (1.85 % CF), Nigrospora oryzae (1.57 % CF) and Phoma glomerata (1.09 % CF). From a total of 131 endophytic species, 101 were tested for their antimicrobial and antioxidant activity. Out of 47 active species, 29.78 % displayed antibacterial activity, 27.65 % showed antifungal activity, 38.29 % exhibited antibacterial and antifungal activity both while only 4.25 % displayed antimalarial as well as antioxidant activity. Twenty-one endophytic fungal species were tested for extracellular production of amylase, xylanase and phosphate solubilization where 76.19 % found to produce amylase, 23.80 % for xylanase and 14.28 % exhibited phosphate-solubilization activity. © Springer India 2014 This work is subject. All rights reserved.
Effect of crop geometries and fertility levels on growth, yield and residual nutrients of cotton (Gossypium hirsutum) hybrids under rainfed condition
(Indian Council of Agricultural Research, 2014) U.N. Shukla; M.S. Khakare; Smita Singh; S.K. Verma
A field experiment was conducted during kharif season of 2008-09 to study the effect of crop geometries and fertility levels on growth, yield and residual nutrients of cotton (Gossypium hirsutum L.) hybrids under rainfed condition. Cotton hybrids MLCH 318 was planted under wider crop geometry of 90 cm × 60 cm which recorded significantly higher growth parameters, monopodial branches and seed cotton weight/plant. However, yield potential of MLCH 318 were higher under closer crop geometry (60 cm × 60 cm) and recorded significantly taller plant, yield attributes and yield of cotton over wider crop geometry of 90 cm × 60 cm (S1) due to more number of plants stand at initial and harvest stages, respectively. Although, cultivar VBCH 2231 (V2) with crop geometry of 90 cm × 60 cm (S1) recorded more in residual status of N (200.44 and 204 kg/ha), P (16.82 and 16.67 kg/ha) and K (496.50 and 489.04 kg/ha), respectively. Among fertility levels, growth characters, yield attributes and yield of cotton with residual N (204.11), P (17.24) and K (495.26 kg/ha) were significantly higher under highest levels of fertility, i.e. 62.5: 31.25: 31.25 kg N: P: K/ha. Thus, it concluded that sowing of cultivar MLCH 318 at crop geometry of 60 cm × 60 cm and fertilized with. 62.5: 31.25: 31.25 kg N: P: K/ha produced significantly higher yield attributes and yield under rainfed condition.
Effect of cultural and chemical weed management practices on yield, economics and nutrient uptake under zero-till direct seeded rice (oryza sativa l.)
(Journal of Pure and Applied Microbiology, 2016) Gaurav; S.K. Verma; R.K. Meena; V.K. Verma; R.N. Meena
An field experiment was conducted during kharif seasons of 2013-14 at Varanasi, UP to evaluate the effect of weed management practices in zero-till direct seeded rice. Results revealed that weed free treatment resulted the highest yield; however, it was not economical due to high cost of cultivation. Pre-emergence application of pendimethalin (1.0 kg ha-1) fb (followed by) early post-emergence application of bispyribac (0.025 kg ha-1) at 18 days after sowing (DAS) was recorded significantly the highest number of effective tillers, grain yield (4290 kg ha-1) and straw yield (5750 kg ha-1), biological yield, harvest index (42.71 %) and NPK uptake as compared to Sesbania co-culture + residue incorporation, Sesbania co-culture fb 2, 4-D and pretilachlor fb hand weeding at 30 DAS and it were at par with the application of pendimethalin fb hand weeding at 30 DAS and pretilachlor fb bispyribac. Application of pretilachlor fb bispyribac at 18 DAS recorded maximum net returns ( 45586) and benefit cost ratio (2.7). None of the treatment as effective as weed free with respect to reduction of density and dry weight of weeds, crop growth, yield attributes and yield, and nutrients uptake.
Effect of mulching and herbicides on weeds, yield and economics of greengram (Vigna radiata L.) grown under eight-year old agrihorti system
(Gaurav Publications, 2017) S.K. Verma; S.K. Prasad; Sushil Kumar; S.B. Singh; Ravi Prakash Singh; Y.V. Singh
A field experiment with the objectives to understand the effect of mulching and herbicides on weed infestation and greengram yield involving two factors viz., mulching (no mulching, dust mulching and paddy straw mulching) and herbicidal treatments (weedy check, hand weeding at 20 and 40 days after sowing, pendimethalin pre-emergence @1000 g/ha, imazethapyr post-emergence @ 100 g/ha, and pendimethalin pre-emergence @ 1000 g/ha followed by imazethapyr post-emergence @ 100 g/ha) was undertaken in splitplot design with three replications at South Campus, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, India. Results revealed that dust mulching and sequential application of pendimethalin followed by imazethapyr recorded lower weed density, weed dry weight, nutrients depletion by weed and maximum crop yield as well as net returns over rest of the mulching and herbicidal treatments. Therefore, it is suggested that the combination of mulching and herbicides may be used for effective weed management and optimal yield of greengram under agri-horti system.
Effect of nitrogen and sulphur on growth, yield and nutrient uptake by Indian mustard (Brassica juncea) under rainfed condition
(2011) Santosh Kumar; S.K. Verma; T.K. Singh; Shyambeer Singh
A field experiment was conducted during winter (rabi) seasons of 2003 to 05 at Varanasi to find out the response of Indian mustard (Brassica juncia L. Czernj and Cosson) to four levels of nitrogen (0, 40, 60 and 80 kg N/ha) and four levels of sulphur (0, 15, 30 and 45 kg S/ha) under rainfed conditions. Application of 80 kg N/ha significantly improved seed yield (1.17 and 1.28 tonnes/ha), stover yield, nitrogen uptake (54.26 and 57.52 kg/ha), protein content and oil content, probably due to better crop growth and yield attributes of Indian mustard. Among the sulphur level, 45 kg S/ha being at par with 30 kg S/ha gave significantly higher seed yield (1.18 and 1.26 tonnes/ha) stover yield, sulphur uptake (20.07 and 21.27 kg/ha) and oil and protein content. Agronomic efficiency and apparent recovery was maximum at 60 kg N/ha and 15 kg S/ha, and it declined with further increases in the levels of nitrogen and sulphur. Optimum economic dose of nitrogen was 39.5 - 46.3 kg/ha and 24.5 kg S/ha. Maximum net returns and benefit : cost ratio were observed with the application of 80 kg N and 45 kg S/ha, respectively.
Effect of nitrogen and sulphur on growth, yield and nutrient uptake by Indian mustard (Brassica juncea) under rainfed condition
(2009) Santosh Kumar; S.K. Verma; T.K. Singh; Shyambeer Singh
A study was conducted during winter (rabi) seasons of 2003-05 to find out the response of Indian mustard to four levels of nitrogen (0,40, 60 and 80 kg N/ha) and four levels of sulphur (0,15,30 and 45 kg S/ha) under rainfed conditions. Application of 80 kg N/ha significantly improved seed yield (1.27 t/ha), stover yield, nitrogen uptake (55.9 kg/ha), protein content and oil content, probably due to better crop growth and yield attributes of Indian mustard. Among the sulphur level, 45 kg S/ha being on par with 30 kg S/ha gave significantly higher seed yield (1.25 tonnes/ha), stover yield, sulphur uptake (20.7 kg/ha) and oil and protein content. Agronomic efficiency and apparent recovery was maximum at 60 kg N/ha and 15 kg S/ha, and it declined with further increases in the levels of nitrogen and sulphur. Optimum economic dose of nitrogen 39.5 - 46.3 kg/ha and 24.5 kg S/ ha. Maximum net returns and benefit : cost ratio were observed with the application of 80 kg N and 45 kg S/ha, respectively.
Effect of row arrangements on quality and nutrient dynamics of linseed (Linum usitatissimum l.) + dwarf field pea (Pisum sativum l.) intercropping association in irrigated condition
(Journal of Pure and Applied Microbiology, 2016) Shiv Bahadur; S.K. Verma; Surajyoti Pradhan; Lala Ram; R.N. Maurya; S.P. Maurya
Field experiments were conducted during winter season 2013-14 to study the effect of various row arrangements on quality and nutrient dynamics of linseed + dwarf field pea were investigated. The highest grain and straw yield, protein and oil content were recorded in T8 followed by T9 whereas highest protein and NKP content were recorded in T11 followed by T5. In case of dwarf field pea highest grain, straw and protein yield was recorded in T11 followed by T5 whereas highest protein and NPK content were recorded in T8. None of the row arrangement was show superiority over sole crop of either linseed or field pea.
Effect of sowing and weed control methods on nutrient uptake and soil fertility in direct-seeded rice (Oryia sativa)
(Indian Council of Agricultural Research, 2021) Vijay Pratap; S.K. Verma; Anchal Dass; Deepak Kumar Yadav; A.J. Madane; Rakesh Maurva; Peeyush Kumar Jaysawal
A 2-year field experiment consisting of 3-planting methods and 5-weed control options was conducted in a three- time rcplicatcd split-plot design at Varanasi during kharif 20\ 6-17 to assess the nutrient uptake by direct-seeded rice (Oryza sativa L.) and available nutrient status of soil under different methods of establishing crop and managing weeds.Zero-till direct-seeded rice (ZT-DSR) + residue + Sesbania brown manuring (SBM) recorded lower density and dry-weight of weeds, higher organic carbon (OC), available N, P and K in soil and enhanced N, P and K uptake by 8.9,6.7,7.8% and 23.7,24.5 and 10.2% in grain and straw, respectively, over conventionally-tilled direct-seeded rice (CT-DSR) + SBM.Among weed control options, the use of pendimethalin (1000 g/ha)Jb chlorimuron + metsulftiron (4 + 4 g/ha, 25 DAS) + 1 HW (45 DAS) resulted in lower density and weeds, higher OC, available N, P and K in soil and improved N, P and K uptake in grain and straw by 23.6, 20.9 and 33.0 and 26.7, 25.5 and 26.6%, respectively over weedy check.However, higher EC andpH and lower nutrient (N, P and K) and protein content in grain and straw were found under weed-free condition.Overall, ZT-DSR + residue + SBM and application of pendimethalin (1000 g/ha)y& chlorimuron + metsulfuron (4 + 4 g/ha, 25 DAS) + 1 HW (45 DAS) proved better with respect to reduction in weed biomass, OC, available soil nutrients (N, P and K) and their uptake in DSR. © 2021 Indian Council of Agricultural Research. All rights reserved.
Effects of irrigation and herbicides on the growth, yield and yield attributes of wheat (Triticum aestivum L.)
(Bangladesh Botanical Society, 2017) S.K. Verma; Ravi Prakash Singh; Sushil Kumar
A field experiment was conducted during the winter (rabi) seasons of 2012-13 at Varanasi, Uttar Pradesh, to study the effect of irrigation and herbicides on the growth, yield and yield attributes of wheat under zero-tillage system. Results revealed that the highest density and dry weight of weeds and the maximum growth parameters, 1000-grain weight, protein yield, straw and grain yield and biological yield were recorded with the application of irrigation at 40 mm CPE over irrigation at 60 and 80 mm CPE. Among herbicidal treatments, application of sulfosulfuron (25 g/ha) resulted the lowest density and dry weight of weeds, the highest weed control efficiency and the lowest weed index thereby increased plant growth and yield attributes which produced the highest straw and grain yield, biological yield, protein content and protein yield over metribuzin and these were at par with metsulfuron methyl. None of the herbicidal treatments was found effective as weed free with respect to weeds, crop growth and yield.
Endophyte roles in nutrient acquisition, root system architecture development and oxidative stress tolerance
(John Wiley and Sons Inc, 2021) S.K. Verma; P.K. Sahu; K. Kumar; G. Pal; S.K. Gond; R.N. Kharwar; J.F. White
Plants associate with communities of microbes (bacteria and fungi) that play critical roles in plant development, nutrient acquisition and oxidative stress tolerance. The major share of plant microbiota is endophytes which inhabit plant tissues and help them in various capacities. In this article, we have reviewed what is presently known with regard to how endophytic microbes interact with plants to modulate root development, branching, root hair formation and their implications in overall plant development. Endophytic microbes link the interactions of plants, rhizospheric microbes and soil to promote nutrient solubilization and further vectoring these nutrients to the plant roots making the soil-plant-microbe continuum. Further, plant roots internalize microbes and oxidatively extract nutrients from microbes in the rhizophagy cycle. The oxidative interactions between endophytes and plants result in the acquisition of nutrients by plants and are also instrumental in oxidative stress tolerance of plants. It is evident that plants actively cultivate microbes internally, on surfaces and in soils to acquire nutrients, modulate development and improve health. Understanding this continuum could be of greater significance in connecting endophytes with the hidden half of the plant that can also be harnessed in applied terms to enhance nutrient acquisition through the development of favourable root system architecture for sustainable production under stress conditions. © 2021 The Society for Applied Microbiology
Evaluation of barnyard millet diversity in central Himalayan region for environmental stress tolerance
(Cambridge University Press, 2017) A.K. Trivedi; L. Arya; S.K. Verma; R.K. Tyagi; A. Hemantaranjan
The mountain ecosystem of the Central Himalayan Region is known for its diversity of crops and their wild relatives. In spite of adverse climatic conditions, this region is endowed with a rich diversity of millets. Hence, the aim of the present study was to explore, collect, conserve and evaluate the diversity of barnyard millet (Echinochloa frumentacea) to find out the extent of diversity available in different traits and the traits responsible for abiotic stress tolerance, and to identify trait-specific accessions for crop improvement and also for the cultivation of millets in the region as well as in other similar agro-ecological regions. A total of 178 accessions were collected and evaluated for a range of morpho-physiological and biochemical traits. Significant variability was noted in days to 50% flowering, days to 80% maturity, 1000 seed weight and yield potential of the germplasm. These traits are considered to be crucial for tailoring new varieties for different agro-climatic conditions. Variations in biochemical traits such as lipid peroxidation (0·552-7·421 nmol malondialdehyde formed/mg protein/h), total glutathione (105·270-423·630 mmol/g fresh weight) and total ascorbate (4·980-9·880 mmol/g fresh weight) content indicate the potential of collected germplasm for abiotic stress tolerance. Principal component analysis also indicated that yield, superoxide dismutase activity, plant height, days to 50% flowering, catalase activity and glutathione content are suitable traits for screening large populations of millet and selection of suitable germplasm for crop improvement and cultivation. Trait-specific accessions identified in the present study could be useful in crop improvement programmes, climate-resilient agriculture and improving food security in areas with limited resources. Copyright © Cambridge University Press 2017.
Factors regulating copper uptake in a cyanobacterium
(Springer-Verlag, 1990) S.K. Verma; S.P. Singh
Copper uptake in the diazotrophic cyanobacterium Nostoc calcicola was found to be typically biphasic, comprising rapid binding of the cations to the cell wall (during the first 10 min) followed by the subsequent metabolism-dependent intracellular uptake for at least 1 h, with a curvilinear kinetics saturating at 40 μM (Km 25.0 μM, Vmax 3.0 nmol Cu mg-1 protein min-1). The cellular Cu uptake was light- and ATP-dependent, and the addition of 3(3,4-dichlorophenyl)-1,1-dimethylurea or exogenous ATP proved that the energy to drive Cu transport was derived mainly through PS II reactions. The application of metabolic inhibitors and uncouplers like carbonylcyanide p-nitrofluoromethoxylphenyl hydrazone, N,N′-dicyclohexycarbodiimide, azide, and p-chloromercuribenzoate revealed that -SH group(s), proton gradient across the cell membrane, and ATP hydrolysis were involved in the transmembrane movement of Cu in N. calcicola. While monothiol (2-mercaptoethanol) caused a twofold reduction in Cu uptake rate, dithiol (dithiothreitol) contributed towards a further drop in the cation uptake rate. © 1990 Springer-Verlag New York Inc.
Genetic variability in proso millet [Panicum miliaceum] germplasm of Central Himalayan Region based on morpho-physiological traits and molecular markers
(Polish Academy of Sciences, Institute of Slavic Studies, 2015) A.K. Trivedi; L. Arya; M. Verma; S.K. Verma; R.K. Tyagi; A. Hemantaranjan
Sixteen representative accessions of proso millet [Panicum miliaceum] having distinct traits of agronomic importance were collected from altitudinal range of 510–2,695 m asl in the Central Himalayan Region (CHR) of India. Considerable diversity was found in morpho-physiological traits viz., leaf length (16.80–32.00 cm), leaf width (1.7–2.1 cm), plant height (57.00–134.00 cm), days to 50 % flowering (34–54), days to 80 % maturity (111–144), and 1,000 seed weight (0.68–1.86 g). Collected accessions have been evaluated for a battery of biochemical parameters viz., chlorophyll, carotenoids, lipid peroxidation, cellular hydrogen peroxide, activity of nitrate reductase, lipoxygenase, catalase, peroxidase, superoxide dismutase along with super oxide free radical formation, glutathione (total, reduced, and oxidized), glutathione reductase, glutathione S-transferase, ascorbate (total, reduced, and oxidized), monodehydroascorbate reductase, and didehydroascorbate reductase. The sets of 12 genic-SSRs (simple sequence repeats), 54 ISSR (inter simple sequence repeats), and 40 SRAP (sequence related amplified polymorphism) markers were used to study the level of genetic diversity, and Nei’s gene diversity value of 0.20 was obtained with both ISSR and SRAP markers. SRAP markers showed higher average number of polymorphic bands, % polymorphism, polymorphic information content (PIC), and Shannon information index compared to ISSR markers; genic-SSRs showed no allelic variation. Cluster analysis shows close groupings of germplasm based on morpho-physiological traits as well as molecular markers. The diverse germplasm identified based on molecular markers with considerable diversity in morpho-physiological traits may be utilized for development of climate resilient cultivars. © 2015, Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków.