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Open Access
Exploring native arbuscular mycorrhizal diversity of agricultural lands of Kumaun Himalaya and its potential for plant growth promotion
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-11) Pallavi; Sharma, A.K.
Arbuscular Mycorrhiza (AM) is a symbiotic relation between roots of higher plants and members of Glomeromycota class of fungi. This symbiotic relationship results in increased water and nutrient uptake along with enhanced tolerance towards biotic and abiotic stress of plants. Although commercial AM inoculum are available but, now it is widely accepted that native AM fungi (AMF) are more efficient in imparting benefits to the plant. In the current study, the native mycorrhizal status of ten agricultural lands located at different altitudes of Kumaun Himalaya was studied. The native AMF population was enriched in glasshouse by traditional trap culturing. The potential augmentation of native AMF population by application of Parthenium based biochar was also performed. Further, the enriched AMF was used as inoculum to investigate the potential of native AMF communities to promote plant growth under irrigated and water stressed condition. in wheat (Triticum aestivum) and finger millet (Eleusine coracana). The studied sampling sites showed rich AMF communities with highest spore density of 28 spores/ g soil was observed at highest altitude i.e. Ghorpatta (2185 m asl). The AMF diversity varied along the altitude, however, morphological evidence suggested Funneliformis mosseae and Claroideoglomus claroideum as the common species found across the altitudinal range indicating some influence of same agricultural practices and cropping system. Parthenium biochar amendment at application rate of 5 g/ kg soil enhanced the mycorrhizal activity along with promoting maize (Zea mays) plant growth and foliar nutrient content. After enrichment by trap culturing, the native AMF communities were tested for their plant growth promotion potential in wheat and finger millet. All the developed inoculum improved the plant growth in both crops but the response varied. Nachini and Dwarson were found to be the most effective inoculum and were able to ameliorate drought tolerance in finger millet by enhancing SOD activity and proline content, while reducing the level of MDA and H2O2. Illumina MiSeq results indicated that trap culturing enhanced the population of opportunistic AMF species, out of which unidentified species of Acaulospora genus was the most dominant (56.8 %) and it is possible that this species is responsible for the growth promotion of plants. It is also found that under drought condition external phosphorus application of 15.5 ppm reduced the mycorrhizal intensity in finger millet plants. However, the expression of common symbiotic genes SYMRK and CCaMK didn’t show a statistically significant reduction, thus, they might not be responsible for phosphorus mediated inhibition of mycorrhizal symbiosis.
Open Access
Electroencephalographic and electrocardiographic studies on propofol anaesthesia in sheep
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2011-06) Raj Kumari; Das, Arup Kumar
In this study electroencephalographic and electrocardiographic changes during surgical interventions {viz., placement of central venous catheters (Group-B), docking/ tail amputation (Group-C), bilateral orchiectomy (Group-D) and no surgical stimuli as control (Group-A)} with propofol anaesthesia were assessed in twenty-four (n=24) apparently healthy male sheep. For surgical operations each sheep of this study was premedicated with glycopyrrolate (@ 0.02 mg/kg body weight, IM) and, five minutes after, anaesthesia was induced with propofol (@ 4.00 mg/kg body weight, IV). The parameters in this study included clinical, cardiopulmonary, haematobiochemical and electrocardiographic parameters. Similarly, qualitative electroencephalographic evaluation was done through spectral analysis to generate total power, SEF-90, MF and PPF over 0-30 frequency band width while relative power of different bandwidths viz., , , and was assessed. Rectal temperature and respiration rate has not shown any significant variability in any of the groups during the entire course of experiment. Haemoglobin concentration reduced and this extent was higher in control group than central venous catheterization, docking and castration groups. PCV reduced in all the groups. TEC depicted reduction in control group; however, this fall was not apparent in other groups. Blood glucose decreased initially followed by an increase in three groups after propofol induction while the castration group exhibited a non-significant increase from very beginning. Total serum protein declined in all the groups. A sudden increase in serum triglyceride (TG) was observed at one minute post-propofol induction in all the groups, which later on declined. Propofol has not been able to induce any significant changes in P-wave, QRS wave and T-wave amplitude as exhibited in control group. However, P-wave amplitude increased significantly in animals performed with central venous catheterization. The T-wave amplitude increased nonsignificantly in CVC group while decrease in docking and castration groups. P-wave and T-wave duration has not exhibited any significant difference throughout the course of experiment. However, QRS wave duration decreased in control group and no significant changes were observed in surgical groups. PR segment length reduced in castration group only and none of the other groups exhibited any significant changes. ST segment length exhibited significant increase in control group, non-significant increase in CVC while exhibiting significant fall in castration and docking groups. RR interval exhibited reduction in all the four groups, non-significantly in control while significantly in the three surgical groups. Heart Rate increased in all the four groups. EEG analysis showed an increase in total power, median frequency, theta frequency, peak power in all group, and after a transient increase reduction in spectral edge frequency and alpha frequency. However delta frequency showed an increase after a transient decrease and a marked decrease in beta frequency after propofol injection. It was concluded that propofol to some extent possess analgesic effect and may be useful in husbandry practices/ day case surgery. However, evaluation of analgesic effects of propofol needs further investigation.
Open Access
Effect of manual and chemical methods of weed management on potato (Solanum tuberosum L.)
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-06) Lavlesh; Manoj Raghav
The present investigation was undertaken to evaluate the “Effect of manual and chemical methods of weed management on potato (Solanum tuberosum L.)” at Vegetable Research Centre of G.B. Pant University of Agriculture and Technology, Pantnagar (Uttarakhand) during rabi season of 2014-2015. The experiment was laid out in Randomized Block Design consisting of seven treatments replicated thrice. During the study, observations on per cent emergence, plant height, number of haulms per hill, fresh and dry weight of weeds, number of monocot, dicot and total number of weeds at 30, 45, 60 days after planting (DAP) and at de-haulming stage, fresh and dry weight of plants at de-haulming stage were recorded. In addition, grade wise number and weight of tubers per plot and per hectare, total number of tubers and total tuber yield per hectare, marketable yield per hectare, harvest index, dry matter content, protein content and specific gravity of tubers, nitrogen, phosphorus and potash uptake by haulm, tuber, plant and weeds were also recorded. Besides this, to assess the profitability of treatments, cost of cultivation, net profit and benefit: cost ratio were also worked out. The findings of present investigation revealed that performance of potato crop was significantly influenced by different weed control treatments. Among all treatments, herbicide metribuzin @ 0.75 kg a.i./ha pre emergence (T6) was found best with respect to overall plant growth, yield and quality parameters with a total yield (305.43 q/ha), net return (`147497.36) and benefit: cost ratio (1.93). Based on overall performance, it could be concluded that under prevalent climatic conditions of Uttarakhand tarai region, herbicide metribuzin @ 0.75 kg a.i./ha pre emergence is the best in terms of higher and economic yield of potato. Hence, recommended for commercial cultivation, provided all other scientific management practices are followed.
Open Access
Rhizospheric bacterial diversity in different Dalbergia sissoo Roxb. provenances
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-08) Joshi, Samiksha; Sahgal, Manvika
Dalbergia sissoo Roxb., common name shisham is a leguminous tree known internationally for its priced timber. Therefore, there is an urgent need to understand the cause and ways to control large scale mortality of mature trees in natural forests. Soil microbes play an important role in tree growth and health. Hence, a comparative study of bacterial communities in shisham rhizosphere at three provenances Lachhiwala, Tanakpur and Pantnagar was carried out through illumina-MiSeq sequencing. The bacterial community composition and diversity based on V3-V4 16S rDNA region was variable and distinct for each provenance. The bacterial diversity index values indicated by species richness (Chao metric), species richness and evenness (Shannon metric) and count of unique OTUs (observed species metric) were significantly higher at Pantnagar than at Lachhiwala and Tanakpur with highest coverage for Lachhiwala (88.86%) and least for Tanakpur (67.19%). diversity analysis depicted closer relationship between rhizospheric bacterial diversity at Tanakpur and Lachhiwala (both healthy forests) than at Pantnagar (forest with mortality). Phylum Proteobacteria was abundant at Lachhiwala and Tanakpur whereas Acidobacteria predominated at Pantnagar. Amongst genera, Pseudomonas, Flavobacterium, Bacillus, Paenibacillus, Sphingomonas, Nitospirae and Massilia were abundant at Lacchiwala and Tanakpur. However, Williamsia, Blastocatella, Methylobacterium, and Brevibacterium at Pantnagar. Metagenomic bacterial diversity was linked to several soil biotic (population and enzyme activities) and abiotic properties (pH, organic carbon, EC and available N, P, K and micronutrients). Highest bacterial count was recorded at Tanakpur followed by Lachhiwala and Pantnagar. Soil enzyme activities such as acid and alkaline phosphatases and urease were highest at Lachhiwala. In contrast FDA and Dehydrogenase were highest at Tanakpur. A strong positive correlation was observed between all enzyme activities and soil nutrients (macro and micro). Since phosphatase activities and available phosphate in soil was higher so phosphate solubilizing bacteria (PSB) were recovered and characterized. Inorganic phosphorous solubilizing ability of bacteria ranged between 285.78 μg ml-1 to 891.38 μg ml-1 These PSB’s exhibited multiple plant growth promoting traits also. In all 18 PSBs were distinguished into seven ARDRA groups. These were identified as Pseudomonas sp., Klebsiella sp., Streptomyces sp., Pantoea sp., Kitasatospora sp., Micrococcus sp. and Staphylococcus sp. through 16SrDNA sequence analysis. Out of eighteen, sixteen bacterial isolates were positive for 82 bp pqq C gene whereas six for 72 bp pqq A gene.
Open Access
Standardization of floral preservatives for storage and vase life enhancement of Gladiolus grandiflorus var. Nova Lux
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-06) Belwal, Sheeba; Bhuj, B.D.
Present investigation was carried out during 2018-19 at Model Floriculture Centre and Department of Horticulture at G.B. Pant University of Agriculture and Technology, Pantnagar Uttarakhand. The objective of the investigation was to study the effects of various floral preservatives on storage as well as vase life of Gladiolus grandiflorus var. Nova Lux which followed a completely randomized design in laboratory conditions. The experiment had thirteen treatment combinations of sucrose, 8 Hydroxy quinoline citrate (8-HQC) and AgNO3. Three replications were given per treatment which intrinsically followed 3 further replications. The influence of floral preservatives showed statistically significant results for various floral characters such as floret diameter, longevity, spike length, preservative uptake, floret opening percentage, blooming period etc. over the control. For storage life, the optimum treatment combination recorded as per the data analyzed is found to be of T2 (sucrose 3%) of 15.44 days over the control showing 10.29 days. For vase life, the optimum treatment combination recorded as per the data analyzed is found to be of T8 (8-HQC 300 ppm, sucrose 6%) of 11.11 days over the control T1 showing vase life duration of 8.46 days.
Open Access
Development and characterization of rare earth oxide-polypyrrole nanocomposites
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-08) Rekha; Sand, N.K.
A series of rare earth oxides (REOs)/polypyrrole (PPY) nanocomposites (RPCs) were synthesized through surfactant assisted chemical oxidative polymerization. The polymerization was followed by blending pyrrole with REOs at various concentration ranging 7 to 21 (%, w/w). For this purpose, REOs selected were Ho2O3 and Er2O3. RPCs were characterized through fourier transformed infra-red, X-ray diffraction, energy-dispersive spectra, atomic force, scanning electron microscopy (SEM), simultaneous thermogravimetric-differential thermal analysis-differential thermogravimetry and cyclic voltammetry. Semiconducting behaviour of electrodes derived from PPY and RPCs was investigated from 298 to 393K at selected voltages. Electrodes derived from PPY show semiconducting behaviour with DC conductivity (σ DC, mS/cm) ranging 1.94–292.95. Under identical conditions, electrodes derived from Ho2O3 and Er2O3 display σ DC in the range of 2.61-534.87 and 2.31-475.89 respectively. Simultaneous imaging of electrodes during temperature regulated σ DC measurements through SEM reveals thermal stability of electrodes in the range of 353 to 373K. Cyclic voltammetry (CV) in combination with DC polarization reveals electroactive nature of electrodes, that was increased with concentration and nature of REOs. In general, electrodes derived from Ho2O3 display improved semiconducting, electrochemical behavior and controlled rate of corrosion over Er2O3 electrode. The present study delivers method of fabrication of electrodes for semiconducting and electrochemical applications.
Open Access
Bioinformatics analysis of camalexin biosynthetic pathway and studies on defense responses of MAP2K4/MAP2K9/MAPK3 mutants during pathogenesis of Alternaria blight in Arabidopsis thaliana
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-08) Gaur, Manu; Pandey, Dinesh
Alternaria blight is one of the most destructive fungal diseases which seriously hamper productivity of Brassica oilseeds in India. Alternaria brassicae is the main pathogen of the disease which produces chlorotic, necrotic toxins and phytohormones to cause the disease. These disease determinants have been known to affect various genes/ proteins of cell cycle and cell death pathways in susceptible Brassica plants to cause the disease and enable the pathogen to follow a semibiotrophic life style. It is being speculated that Alternaria brassicae pathogen affects highly conserved MAP kinase signal transduction pathway to cause the disease. In Arabidopsis , some of the MAP kinases including MPK3, MKK4, MKK9, are responsible for synthesis of ‘Camalexin’ which is one particular phytoalexin involved in mediating defense response against the necrotrophic fungal pathogen viz. ‘Botrytis cinerea’. In the present investigation, role of MPK3, MKK4 and MKK9 in triggering Camalexin based defense response of Brassica plant towards Alternaria brassicae was studied by using Arabidopsis mutants for these kinases and Bioinformatics analysis. Following the infection of Alternaria brassicae pathogen, disease index of mkk4, mkk9 and mpk3 mutant plants was observed to be more than that of wild type plants of Arabidopsis thaliana. These observations suggested increased susceptibility of mpk3, mkk4, mkk9 mutants of Arabidopsis for Alternaria blight due to decreased camalexin biosynthesis or differential expression of proteins. In order to study differential expression of proteins, the proteins were extracted from infected leaf samples of both wild type and mutant Arabidopsis plants and protein profiles were compared at initial, middle and late stage of infection by performing one dimensional SDS PAGE analysis. In wild and mutant plants of Arabidopsis, the protein extractability decreased as the disease progressed from early to middle stage due to degradation of host proteins and increased from middle to late stage due to synthesis of new proteins. SDS PAGE based analysis of proteins extracted from leaves of wild type and mutant Arabidopsis plants indicate differential expression of proteins in form of expression of unique prroteins and downregulation or upregulation of proteins during disease progression from early to late stage of pathogenesis in Arabidopsis mutants and wild type plants. MKK4/MKK9/MPK3 signalling module involved in biosynthesis of camalexin during defense response of B. rapa towards, Alternaria brassicae pathogen was elucidated with the help of Molecular modelling, docking, and protein-protein interaction analysis of MAP kinases retrieved from Brassica rapa genome. Network Biology based in silico approach was followed to identify linkages of MKK4, MKK9 and MPK3 with 51 known defense related genes through construction of PPI network. MPK3 was observed as major hub to which large numbers of defense regulated genes/proteins are connected. This suggests that MPK3 is largely responsible for activation of large number of defense related genes besides camalexin biosynthetic genes. These studies will open up new avenues for engineering defense pathway in Brassica for preventing losses caused by Alternaria blight disease.
Open Access
Documentation of the bacterial and diazotrophic diversity from Garhwal Himalaya through culturable and unculturable approaches
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-07) Saurabh Kumar; Goel, Reeta
To study the bacterial diversity and soil physiochemical properties of Garhwal Himalaya, total five soil samples were collected from different locations of Garhwal Himalaya namely Harsil, Gangotri, Uttarkashi, Dhanaulti and Kandakhal. Based on the primary screening through quantification of 16SrDNA and nifH genes and 16SrDNA DGGE analysis, Gangotri and Dhanaulti were selected for further study. Comparative soil physiochemical characterization of the both soil samples revealed that the Kandakhal soil was neutral in pH, poor in soil organic matter (SOM) and total Kjeldal nitrogen (TKN) and rich in micronutrient. However, Gangotri soil was found alkaline, rich in TKN and SOM and poor in mineral nutrients. Thus, it was found that the soil physicochemical properties vary significantly with the altitude. Metagenomics of Kandakhal soil revealed that the Proteobacteria (31%) was the major phylum followed by Bacteroidetes (20%), Fermicutes (9%), Acidobacteria (7%), Actinobacteria (6%) and Chloroflexi (5%). However, in phylum Proteobacteria, Alphaproteobacteria (8%), Betaproteobacteria (8%), Gammaproteobacteria (8%) and Deltaproteobacteria (7%) were uniformly distributed. On the other hand in Gangotri, total 31 bacterial phyla were observed where, Proteobacteria (38.49 %), Acidobacteria (17.88 %), Actinobacteria (14.48 %), Bacteroidetes (7.89 %), Gemmatimonadetes (7.87 %) and Chloroflexi (5.94 %) were dominant bacterial phyla. However, in phylum Proteobacteri, Alphaproteobacteria (16.88%) was the most abundant bacterial class followed by Betaproteobacteria (9.44%). Presence of large numbers of unidentified OTU in Gangotri soil suggests that it has unique bacteria diversity. Further, an indigenous diffusion chamber was designed and incubated in-situ for cultivation of readily not cultivable bacterial from Gangotri soil which revealed the potential of this device for isolation of bacteria which were previously difficult to isolate from conventional methods. Moreover, six psychrophilic diazotrophic bacteria were isolated form Gangotri soil and identified as Pseudomonas helmanticensis, Arthrobacter humicola, Brevibacillus invocatus and Pseudomonas mandelii etc. However, no psychrophilic diazotrophic were isolated from the Kandakhal soil. Further investigation was carried out to study the cold adaptation in Pseudomonas helmanticensis at molecular level. This was the first time when proteomics of psychrophilic diazotrophs Pseudomonas helmanticensis was reported under the cold stress. Differential proteomics of P. helmanticensis under cold stress through LC-MS analysis revealed that majority of upregulated and unique proteins expressed under cold stress were functionally involved in RNA metabolism, translation and energy production. Moreover, major upregulated proteins were molecular chaperones which assist in the proper protein folding and RNA stability at low temperature. Therefore, both culture dependent and independent studies revealed that the Kandakhal and Gangotri soil harbor rich bacterial diversity. However, diversified culturable psychrophilic nitrogen fixers were only present in the Gangotri soil. Thus, Garhwal region of the western Indian Himalaya is rich in cold adapted bacterial diversity which could be explored for basic understanding of cold adaptation besides its applied significance.
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Delineating the redox signaling network under oxidative stress through over expression of Ecapx1 in Eleusine coracana
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-12) Pande, Anjali; Arora, Sandeep
Global warming has emerged as one of the biggest threats to agriculture in the last two decades. In arid and semi-arid regions, where temperatures are already close to the physiological maxima for crops, higher temperatures may increase the incidence of heat stress in crops; negatively affecting the growth and productivity. Under such conditions, development of climate resilient crops is a dire need. As reactive oxygen species are a common denominator in the effect of various environmental stresses, therefore it is important to understand the signaling events in plants that are implicated in activating the anti-oxidative defense in plants and providing redox homeostasis. Towards this objective, we successfully developed Exapx1 over-expressing E. coracana plants. The transgenic lines were developed by using Agrobacterium mediated transformation method. The transgenic lines with increased ascorbate peroxidase activity where used to delineate the redox sensing mechanisms that are involved in providing protection from oxidative stress. The transgenic lines were morphologically similar to the wild type plants and had similar PS-II activity. Increased expression of apx1 gene in the transgenic lines could induce higher expression of superoxide dismutase and monodehydroascorbate reductase genes, under stress; but no significant increase in dehydroascorbate reductase and glutathione reductase gene expression was recorded. Over-expression of Ecapx1 gene could selectively (and not universally) induce the expression and activity of other anti-oxidant enzymes of the AsA-GSH pathway, indicting the existence of a cross talk or signaling mechanism in plants, for coordinated expression of these enzymes. On exposure to stress, the transgenic lines accumulated lesser H2O2 as compared to the wild type plants and also had lower proline levels. An effective control over H2O2 levels (through Ecapx1 over-expression) prevented undue activation of specific antioxidative enzymes like DHAR and GR, while helping to maintain the redox balance of the cells under stress. Incidentally, the transgenic lines had higher reduced to total ascorbate ratio, than the wild type plants, that was responsible for sensing the increased influx of ROS and activate the cellular anti-oxidative defense network, through down-stream signaling.

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