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Open Access
Screening of chickpea (Cicer arietinum) rhizosphere for identification of potential growth-promoting and antagonistic rhizobacterial strains
(SKUAST Kashmir, 2023) Imran Ramzan; Malik, Asif Aziz
Plant growth promoting bacteria play a substantial part in plant growth promotion and disease suppression. The present study was aimed to isolate, characterize, screen and select most outstanding PGPR isolates from Chickpea rhizosphere. During the course of study a total of 200 isolates were obtained from four (4) sites in District Budgam and Baramulla respectively. Microbiological study revealed wide variation in colony features. Biochemical characterization of the isolates resulted in the identification of five (5) dominant microbial species viz., Pseudomonas, Azotobacter, PSB, Escherichia coli, Rhizobium. The PGPR isolates showed varied results for growth promotion attributes. The maximum IAA was produced by Rhizobium (RHZ-17) followed by Escherichia coli (E.coli-17), Azotobacter (AZT-14), Pseudomonas (PS-17), PSB (PSB-24) with 29.04, 27.71, 23.68, 14.11, 9.87µgml-1 respectively. Phosphate solubilization was exhibited by Pseudomonas (PS-15), Phosphate solubilizing bacteria (PSB-28), Escherichia coli (E.coli-27), Rhizobium (RHZ-39), Azotobacter (AZT-19) with Pseudomonas (PS-15) showing maximum phosphate solubilizing efficiency (550%). Moreover Pseudomonas (14), Azotobacter (18), PSB (22), Escherichia coli (12), Rhizobium (16) isolates showed positive reaction for H2S. Ammonia production was reported only in Pseudomonas (19), Azotobacter (19), PSB (26), Escherichia coli (18) and Rhizobium (25) isolates. The findings on potential capacity of PGPR isolates to suppress growth of Fusarium oxysporum (fungal pathogen) revealed that Pseudomonas, Azotobacter, PSB, Escherichia coli, and Rhizobium isolates were able to check the growth of the pathogen. Maximum biocontrol ability was shown by Rhizobium (RHZ-17), followed by Pseudomonas (PS-13), PSB (PSB-31), Rhizobium (RHZ-31), Escherichia coli (E.coli-35) and Azotobacter (AZT-19) with 43.44, 34.66, 33.22, 32.89 and 32.8 inhibition percent. These strains were also analysed on molecular basis and the strains were identified as Bacillus megaterium and Bacillus anthracis by 16S rRNA gene sequencing molecular techniques from Budgam and Baramulla Districts respectively.
Open Access
Molecular and Functional Diversity of Psychrophilic Potassium Solubilizing Bacteria (KSB) in High Density Apple Orchard Soils of District Baramullah, Jammu and Kashmir (J&K)
(SKUAST Kashmir, 2023) Aiman Ashraf; Baba, Zahoor Ahmad
Soil potassium (K) supplement depends intensively on the application of chemical fertilizers, which have substantial harmful environmental effects. However, some bacteria can act as inoculants by converting unavailable and insoluble K forms into plant-accessible forms. Such bacteria are an eco-friendly approach for enhancing plant K absorption and consequently reducing utilization of chemical fertilization. Therefore, the present research was undertaken to isolate, screen, and characterize the psychrophilic K solubilizing bacteria (KSB) from the rhizosphere soils of high-density apple orchards of District Baramullah, a district in North Kashmir, Jammu & Kashmir, India. A total of 43 isolates were obtained but only 10 were screened for potassium solubilizing ability at 15°C. Firstly the isolates were screened for potassium solubilizing ability on Alexsandrow agar plates by formation of solubilization zones at 15°C after 72 hours of incubation. The isolate Ksb(achbl-B)S3 recorded maximum solubilization zone (30 mm) with 857.1% solubilization efficiency followed by Ksb(achbl-A)S1 (29 mm) & 725%, Ksb(achbl-D)S2 (25mm) & 609% , Ksb (dgp-A)S3 (22 mm) & 550%, Ksb (achbl-C)S2 (20mm) & 392% , Ksb (selu)S3 (14mm) & 335.9% , Ksb (nopr)S1 (12mm) & 302.4%, Ksb (wdr-A)S2 (13 mm) & 254.9%, Ksb (vzr)S1 (12 mm) & 235% and Ksb (mukm)S2 (11 mm) & 218%. Secondly the selected isolates were examined for their ability to release K from broth media supplemented with 1 per cent muscovite mica at 15°C after 10 days of incubation. Among all the 10 isolates examined, Ksb(achbl-B)S2 released maximum amount (28.9 µg/ml) of K from the mica followed by Ksb(achbl-A)S1 (26.1 µg/ml), Ksb(achbl-D)S2 (16.46 µg/ml), Ksb(dgp-A)S3 (14 µg/ml) , Ksb(achbl-C)S2 (12.96 µg/ml), Ksb(selu)S3 (9.1 µg/ml), Ksb(nopr)S1 (8.7 µg/ml), , Ksb (wdr-A)S2 (8.63 µg/ml) Ksb(vzr)S1 (8.1 µg/ml) and Ksb(mukm)S1 (7.6 µg/ml). Based on molecular characterization (through the 16S rDNA sequencing approach), the isolate Ksb(achbl-B)S2 was identified as Pseudomonas frederiksbergensis, isolate Ksb(achbl-A)S1 as Pseudomonas orientalis strain and isolate Ksb(achbl-D)S2 as Pseudomonas putida.
Open Access
Effect of Harvesting Time on Seed Physiological Quality and Storability of Yellow French Bean (Phaseolus vulgaris L.) Seeds
(SKUAST Kashmir, 2022) Ume Salma; Khan, Farooq Ahmad
A field experiment on French bean was conducted during the year 2020 to determine the dynamic changes in physico-chemical attributes of developing seeds and optimum harvesting time for optimim seed quality and storability. Healthy and uniform sized seeds of Yellow French bean (bush type) were sown in well prepared field at a planting distance of 30 × 10cm and all the intercultural operations were followed as per the package of practices. There were seven treatments of pod harvesting time viz, 20, 25, 30, 35, 40, 45 and 50 days after anthesis (DAA) and each treatment was replicated thrice. For each replication 200 flowers were tagged and labeled with anthesis date. The tagged pods were picked after the specified period of time and air dried seeds were analyzed for their physico-chemical as well as germination attributes. Harvested seeds were also subjected to accelerated ageing treatment (AA) at 45±2°C temperature plus 95±5 percent RH. Their viability (tetrazolium test) and germination potential were examined. Harvesting time significantly influenced the seed and pod characters and highest weight of fresh pod (2.12g), pod length (14.66cm), pod circumference (3.88cm) and seed to pod ratio (0.82) were recorded at 40 DAA followed by 45 and 50 DAA. Harvesting at 40 DAA also resulted in highest fresh weight of seed (1.73g/pod), dry weight of seed (0.64g/pod) and seed test weight (47.88g) of seeds coupled with most attractive seed colour value (4.00). However, the highest seed protein (214.30 mg/g DW) and starch (634.00 mg/g DW) contents were recorded at 50 DAA while seeds of 40 DAA resulted in maximum sugar content (98.70 mg/g DW). Seeds harvested at 40 DAA also resulted in highest seed germination percent (90.33) and germination rate (0.38seed/day) with least value of MGT (2.62days). In addition, harvesting at 40DAA resulted in highest root and shoot length (24.08 and 18.50cm), root and shoot dry weight (1.65 and 1.09g) and SVI-I and SVI-II (3847.17 and 247.82) against the minimum values of the (AA) attributes at 20 DAA. Tetrazolium chloride test of artificially aged seeds showed maximum seed viability (91%) at 40 DAA followed by 45 (64.00, 50 (55.33) and 35 (51.00) days after harvest. Germination test of AA seeds depicted that seeds harvested at 40DAA resulted in highest germination percent (84%), radicle length (8.40cm), plumule length (17.03cm) and dry weight of seedling (2.03 g/seedling) which in turn produced highest SVI-I (2135.94) and SVI-II (170.50) followed by 45 and 50 DAA. Thus, present study suggests that harvesting of Yellow French bean pods at 40 DAA resulted in maximum growth of pods with improved physico-chemical quality of seeds which in turn resulted in highest seed germination potential and lowest deterioration under AA treatment.
Open Access
Evaluation and Standardization of Seed Priming in Carrot (Daucus carota L.) under optimal and sub-optimal Temperature Conditions
(SKUAST Kashmir, 2022) Rafia Parvez; Bhat, Sajad Ahmad
The present investigation entitled “Evaluation and Standardization of Seed Priming in Carrot (Daucus carota L.) under optimal and sub-optimal temperature conditions” was carried out in the laboratory of Division of Basic Sciences & Humanities, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Shalimar during the year 2020-2021. There were sixteen treatments viz; gibberellic acid, GA3 (100 ppm), salicylic acid, SA (0.5 mM), potassium nitrate, KNO3 (1%), hydropriming along with control (without priming). The effect of priming chemicals was studied at different durations (12, 24, 36, 48 hours) at two temperatures viz; 15oC and 23oC. The experiment was laid in Completely Ramdomized Design (CRD) with three replications. Results showed that at 23oC, the seed germination, emergence and biochemical parameters of carrot seeds were influenced significantly by the application of priming chemical GA3 100 ppm at 48 hours. The maximum values obtained with GA3100 ppm at 48 hours are mean rate of germination (0.494 day -1), coefficient of rate of germination (18.07 % day-1), radicle length (6.64mm), plumule length (4.80mm), germination index (55.66), speed of germination (12.74), final germination percent (95.40 %), seedling vigor index-I (918.99), seedling emergence percent (89.33 %)), Timsons index (26.94), seedling root length (4.93 cm), seedling shoot length (4.70cm), root:shoot ratio (1.050), chlorophyll stability index (95.34%), membrane stability index (83.94%), antioxidant capacity (180.86 mg GAE/g), minimum time to 50% germination (1.02days), minimum mean germination time (2.02 days), minimum time to 50 % emergence (4.27 days), minimum mean emergence time (5.05 days) and minimum lipid peroxidation (0.11 mol g-1 FW). At 15oC, the seed germination, emergence and biochemical parameters of carrot seed were also influenced significantly by the application of priming chemicals and better results were recorded in KNO3 1% at 48 hours viz. mean rate of germination (0.626 day -1), coefficient of rate of germination (17.07 % day-1), radicle length (3.59mm), plumule length (4.19mm), germination index (55.66), speed of germination (11.36) final germination per cent (93.65%), Timsons index (24.24), minimum time to 50% germination (1.27days), minimum mean germination time (1.59 days), seedling vigour index-I (827.86), seedling emergence per cent (84.00 %), seedling root length (4.44 cm), seedling shoot length (4.41 cm), root: shoot ratio (1.013), chlorophyll stability index (95.29 %), membrane stability index (81.76 %), antioxidant capacity (185.93 mg GAE/g), minimum time to 50 % emergence (5.55 days), minimum mean emergence time (8.02 days) and minimum lipid peroxidation (0.13 μ mol g-1 FW). Thus, at optimal temperature (23 oC) application of GA3100 ppm at 48 hours and at sub-optimal temperatures (15oC), KNO3 performed better in terms of different germination, emergence, physiological and biochemical parameters due to the effect of priming in carrot seeds.
Open Access
Effect of Different Seed Soaking and Priming Methods on Physiological Potential of Seed Germination in Okra (Abelmoschus esculantas L.)
(SKUAST Kashmir, 2022) Fasil Fayaz; Khan, Farooq Ahmad
The present investigation entitled “Effect of Different Seed Soaking and Priming Methods on Physiological Potential of Seed Germination in Okra (Abelmoschus esculantas L.)” was carried out in the Plant Physiology Laboratory of Division of the Division of Basic Sciences & Humanities, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Shalimar during the year 2020-2021 to improve the seed vigour and germination potential in okra and see the comparative efficacy of seed soaking and priming on seed germination and seedling establishment attributes. There were nine treatments viz., seed soaking in water for 18 hours (T1), seed soaking in -1.0 MPa solution of PEG-6000 for 24 hours (T2), seed soaking in 100ppm solution of GA3 for 18 hours (T3), seed soaking in 1.5% solution of KH2PO4 for 18 hours (T4), Seed priming with pure water for 18 hours (T5), seed priming with -1.0MPa solution of PEG-6000 for 24 hours (T6), seed priming with 100ppm solution of GA3 for 18 hours (T7) and seed priming with 1.5% solution of KH2PO4 for 18 hours (T8) along with untreated seeds as control (T0). The experiment was laid in completely randomized design (CRD) with three replications. Twenty seeds of each treatment replication were placed in petri-dishes lined with 10 layers of filter paper and saturated with distilled water. The petri-dishes were placed in seed germinator at a temperature of 25°C±2°C for their germination test. Results showed that maximum values obtained with hydro-priming are mean germination rate (0.614 day-1), coefficient velocity of germination (87.3%), synchronization index (0.790), radicle length (31.0mm), plumule length (65.0mm), seed metabolic efficiency (0.777g), reserve mobilization rate (61.00mg/seed) and membrane stability index (69.7%). Total antioxidants (36.37 mg GAE/g DW) and leaf phenol content (73.00mg/100g FW) were found to be maximum in osmo-priming. Harmo-priming showed best results in mean germination rate (0.598-1) day, time to 50% germination (1.20 days), mean germination time (1.30 days) and seedling vigour index-1 (821.6). Water-soaking showed best results in final germination percentage (91.3%), mean germination rate (0.588 day -1), time to 50% germination (1.21 days) and germination index (16.29 days). Hormo-soaking recorded maximum seedling vigour index-2 (47.0), root dry weight (0.164g) and seedling growth rate (11.52mg/day). Nutri-priming was best treatment in stimulating seedling vigour index-2 (46.05), shoot dry weight (0.431g), seedling growth rate (11.51 mg/day), leaf crude protein (44.47 mg/g DW), leaf sugar content (114.97µg/g DW) and leaf chlorophyll content (1.387mg/g FW). However, mean values of the two sets of pre-sowing treatments viz., traditional soaking and priming clarified that for most of the parameters priming treatments were found as better than traditional seed soaking methods.
Open Access
Rhizobacterial Evaluation of Medicinal plants for Growth Promotion and Biocontrol Efficacy
(SKUAST Kashmir, 2022) Parray, Raaqib Rasool; Malik, Ahsaf Aziz
The rhizospheric bacteria known as Plant Growth Promoting Rhizobacteria (PGPR) influence plant growth positively through a number of mechanisms, including phosphate solubilization, siderophore production, biological nitrogen fixation, interference with quorum sensing (QS) signalling and inhibition of biofilm formation, phytohormone production, exhibiting antimicrobial activity. The current study's objective was to extract, describe, screen, and identify the most effective and promising PGPR strain from the rhizosphere of medicinal plants. 92 isolates were received for the study from the medicinal nursery cum demonstration centre, RCFC, NMPB, at the Faculty of Agriculture, SKUAST-K, Wadura. In terms of colony characteristics, there were significant morphological variances in each of the five PGPRs. Following biochemical examination of the samples, it was discovered that 11 isolates had antifungal activity in addition to that 23 Pseudomonas, 26 PSB, 14 Rhizobium, and 18 Azotobacter were isolated on their respective substrates, these PGPR isolates displayed a variety of growth-promoting behaviours. Among Pseudomonas isolates SCKB1 produced (9.17 µg ml-1) the most IAA. In PSB isolates CSPK3 produced (10.21 µg ml-1) the most IAA. However in Azotobacter isolates BCJN2 produced (7.2 µg ml-1) the most IAA. In Rhizobium isolates PHY3 produced (7.1 µg ml-1) the most indole acetic acid. The highest phosphate solubilization effectiveness was demonstrated by TWKP1 (122.99%) among all isolates. Pseudomonas species demonstrated the highest levels of biocontrol activity. Highest biocontrol activity was shown by TWKB2 (53.3%).
Open Access
Studies on Microbial Degradation of Atrazine from Agricultural Soils
(SKUAST Kashmir, 2022) Misbah Rasool
A large number of Atrazine degrading bacterial strains were isolated from atrazine treated rhizosphere soil samples from maize fields from the districts of Baramulla,Budgam and Pulwama.Only ten isolates showed maximum atrazine degradation efficiency in the order of A(d)7 (64%) > A(l)39 (59%) > A(d)8 (54%) > A(d)10 (53.83%) > A(w)6 (46.83%) > A(S)16 (45%) > A(W)12 (43 %) > A(Kl)24 (40.83%) > A(Kr)16 (38%) > A(P)1 (35%) at 100 ppm with an incubation period of 60 hours respectively.Almost all isolates were capable of producing Biuret qualitatively . Ammonical Nitrogen was produced by these bacterial isolates in significantly different quantities in the order of A(d)7 (69%) > A(w)6 (64%) > A(d)10 (59%) > A(S)16 (57%) > A(w)12 (56%) > A(kl)24 (49%) > A(d)8 (44%), A(I)39 (44%) > A(Kr)16 (39%) > A(p)1 (38%) at 100 pm with an incubation period of 60 hours respectively. Among all the 10 isolates ,A(d)7 showed maximum Atrazine degradation, Biuret production, Ammonical Nitrogen and significant phosphate and potassium solubilization (32.16 ug/ml and 26.41 ug/ml ,respectively.From molecular characterization it was evident that A(d)7 showed 98.7% similarity with Arthrobacter nitrophenolics that belonged to phylum Actinobacteria. Rhizosphere soil samples of maize from Pulwama,Budgam,Baramulla were collected and tested for various physico-chemical characteristics.Thes isolates need to be investigated for more beneficial traits , pH was slightly acidic to neutral and ranged from (5.2-7.2) , (5.4-6.91), (5.8-7.4) ,electrical conductivity was normal with ( 0.76-0.99), (0.61-0.87),(0.62-0.86)dS/m ,organic carbon medium to high (0.69- 0.87)% in District Pulwama , medium (0.51%-0.79) and ( 0.56%-0.69)% in District Budgam and Baramulla respectively. Available Nitrogen status in all three Districts was low to medium with (210.47-292.43) kg/ha, (167.21-278.09) kg/ha and (167.8-275.36) kg/ha observed from Pulwama, Budgam and Baramulla respectively. . Population of Atrazine degrading bacterial colonies from District Pulwama, Budgam and Baramulla ranged from 1-38 c.f.u x105/g soil, 3-33 c.f.u x105/g soil , 3-28 c.f.u x105/g soilrespectively .From the current study it can be concluded that all the collected soil samples had good count of Atrazine degrading bacterial isolates.
Open Access
Screening of weed rhizosphere for Production of Quality Bio-inoculants under Kashmir Himalayas
(SKUAST Kashmir, 2022) Baba, Darakshan Hamid; Malik, Mushtaq Ahmad
Plant growth promoting rhizobacteria (PGPR) are the potential bio-resource that build up substantial advantages to the agricultural crops. The use of novel PGPR as bio-inoculant is an alternative sustainable agricultural prac¬tice to improve the soil health, grain quality, increase crop productivity, and conserve biodi¬versity. The aim of the present study was to isolate, characterize, screen and identify most promising and efficient PGPR strain from weed rhizosphere. During the study, 91 isolates were obtained from Agriculture and Horticulture demonstration blocks at Faculty of Agriculture, Wadura, SKUAST-K. Morphologically, a wide variations in terms of colony features were observed in all the five PGPRs. Upon biochemical characterization of the samples, it was observed that 30 isolates belong to the genera Pseudomonas, 20 to PSB, 15 to Rhizobium, 14 to Azotobacter and 12 isolates showed antifungal activity. These PGPR isolates showed varied growth promoting activities on their respective media. The maximum IAA production was shown by Pseudomonas isolate DRKB4 (10.1 µg ml-1). The maximum solubilisation efficiency was shown by TRPV3 (147.8%). Maximum bio-control activity was shown by Pseudomonas species, CDKB1 (42.9%). This area of research will open new horizons to utilize PGPR from weedy grasses for plant growth promotion and yield in nutrient deficient soils which will be of great value for agriculture research and applications.
Open Access
Studies on hemicellulose degrading bacteria from the forest soils of district Baramullah
(SKUAST Kashmir, 2022) Aasif Muhammad; Baba, Zahoor Ahmad
Xylanase enzyme degrades ß-1,4 xylan by cleaving ß -1, 4 glycosidic linkages thus forming usable products such as xylose, xylobiose oligosaccharides. Production of microbial xylanases is preferred over plant and animal sources because of their availability, structural stability and easy genetic manipulation and therefore can be used for the production of extracellular hemicellulases. The present investigation pertaining to “Studies on hemicellulose degrading bacteria from the forest soils of district Baramullah” was carried out in the Division of Basic Science and Humanities, FoA, Wadura, Sopore to explore the potential of resident hemicellulolytic bacteria for the bioconversion of carbon compounds and their population estimation. Thirty forest soil samples were collected from three forest viz., Baramullah, Doabagh and Boniyar of district Baramullah for estimating the population of hemicellulolytic bacteria and revealed that mean population of bacteria was 5.12 ×106 CFU/g soil with a range of 3.21 to 7.56 ×106 CFU/g of soil. Thirty isolates of hemicelluloytic bacterial were isolated from collected soil samples and were screened for hemicelluloytic activity qualitatively. The results revealed that maximum hydrolysis zone was formed in the isolate HD6 (1.91cm), followed by HD24 (1.85cm), HD12 (1.78cm) and least was observed in isolate HD17 with 0.35cm. Fifteen potential hemicellulose degrading bacterial isolates based on qualitative screening were selected for estimating xylanase activity using xylanase assay which reveals that highest xylanase activity was observed in isolate HD7 (35.60±1.39 IUml-1) followed by HD12 (32.75±1.14 IUml-1), HD27 (32.28±1.86 IUml-1) and least was recorded in HD6 with 9.58±1.38 IUml-1 with range of 9.58 to 35.60 IU.ml-1.The three top potential hemicellulose degrading bacterial isolates viz., HD7, HD12 and HD27 based on qualitative and quantitative screening were evaluated for their effect on fermentation period, incubating temperature, inoculum concentration and pH on xylanase activity in order to optimize the conditions of fermentation assay. The results revealed that optimum xylanase activity was observed at pH 8, incubating temperature of 35 °C and inoculum level of 1.5 to 2 per cent after 24 to 48 h of incubation period. The present study thus revealed that temperate forest soils acts as a reservoir for hemicellulose degrading bacteria capable of producing high xylanase enzyme.

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