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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 K solubilizing bacteria (KSB) from the rhizosphere soils of northern India. Overall, 110 strains were isolated, but only 13 isolates showed significant K solubilizing ability by forming a halo zone on solid media. They were further screened for K solubilizing activity at 0 °C, 1 °C, 3 °C, 5 °C, 7 °C, 15 °C, and 20 °C for 5, 10, and 20 days. All the bacterial isolates showed mineral K solubilization activity at these different temperatures. However, the content of K solubilization increased with the upsurge in temperature and period of incubation. The isolate KSB (Grz) showed the highest K solubilization index of 462.28% after 48 h of incubation at 20 °C. The maximum of 23.38 µg K/mL broth was solubilized by the isolate KSB (Grz) at 20 °C after 20 days of incubation. Based on morphological, biochemical, and molecular characterization (through the 16S rDNA approach), the isolate KSB (Grz) was identified as Mesorhizobium sp. The majority of the strains produced HCN and ammonia. The maximum indole acetic acid (IAA) (31.54 µM/mL) and cellulase (390 µM/mL) were produced by the isolate KSB (Grz). In contrast, the highest protease (525.12 µM/mL) and chitinase (5.20 µM/mL) activities were shown by standard strain Bacillus mucilaginosus and KSB (Gmr) isolate, respectively.

There is an immense demand for vermicomposting employing psychrophilic vermiculture (Aporrectodea caliginosa) for management of wastes under the Himalayan ecosystem. Dalweed (weeds from the world-famous urban Dal Lake) and cow manure (CM) are cheaply and abundantly available bio resources in Kashmir valley. Dalweed (DW), disposed of in the heart of the city, ascribes unpleasant effects on tourism and the natural ecosystem. Initial substrate mixtures of DW and CM with different ratios (CM100, DW100, CM80:DW20, CM60:DW40, CM40:DW60 and CM20:DW80) and castings harvested were analyzed for the following parameters: pH, TOC, TN, NO3- P, K, Fe, Zn, C:N, C:P, and C:S ratio. The results of a 56day study revealed in consistency and disparity towards the bio-optimization of coprolites depending upon the type of waste residue and mixture ratio used. Treatments with medium to low dalweed residues (CM60:DW40 followed by CM80:DW20) were found to be optimum and significantly primed chemical properties of castings using A. caligenosa. C:N, C:P, and C:S ratios showed a non-linear response with maximum decrease in C:N ratio by 35%, C:P ratio by 38% in CM100, and C:S ratio by 67% in DW100. Humification ratio, humification index, and percent humic acids were changed across all the treatments with the highest respective values of 21.33 ± 1.05, 11.33 ± 0.76, and 47.83 ± 0.76 for CM60:DW40. Results also showed that the earthworm population and biomass significantly increased with the highest respective increments of 57.53% and 74.88% in CM60:DW40 over initial values. Moreover, the highest number of cocoons (95.67 ± 1.17) were recorded within CM60:DW40 and the lowest in the control (43.33 ± 1.53). Dehydrogenase and fluorescein diacetate activities were inconsistent with the highest in CM40:DW60 (64.64%) and CM20:DW80 (63.54%) respectively over the initial substrates, while highest urease activity (74.40%) was observed from CM100. The results highlight the role of A. caliginosa in sustainable transformation of CM and DW with insightful, beneficial, and priming impacts on castings for its agronomic value.

The temperate climatic regions face the problem of waste accumulation due to lower environmental temperatures. However, these regions harbor cold active microbes viz. psychrotrophic proteolytic bacteria that play an important role in the degradation of protenaceous materials of the waste stream. Hence in the present study psychrotrophic proteolytic bacteria were isolated from waste samples collected from landfill site by using random sampling method under environmental temperature of 10oC. By using serial dilution and spread plate technique a total of 8 morphologically different psychrotrophic proteolytic bacteria were isolated on skim milk agar media at pH of 7.0 and temperature of 10°C after 48hours. Under in-vitro conditions all the isolates produced significant quantities of protease over the control and diameters of hydrolysis zones ranged between 2 to 18 mm at temperature range of 5 to 20oC and after 72 hours. The corresponding quantitative protease activities of the isolates was significant that ranged between 0.5 to 2.25 U/ml and the isolate PB2 was most efficient with highest protease activity of 2.25U/ml at 20oC. Based on 16SrRNA analysis the isolate was identified as Pseudomonas florescence with 96% similarity. It was concluded that the isolates can grow in wide ranges of temperature and could be used for enhanced decomposition of organic wastes during lower temperature conditions in cold regions. Further the isolates could have industrial applications due to the production of cold active proteases that would help economic benefits through energy conservation.

A comparative study of organically and conventionally managed soils under beans was conducted to study the added advantage of organic crop production system over the conventional one. A comparative study of Rhizobium isolates, from the two management systems, for their potential beneficial activities was also carried out.The organically managed soils had better status with respect to physicochemical and microbiological properties and the Rhizobium isolate from the organic farm possessed significantly higher plant growth promoting potential as compared to those from the conventional farms. Organic farm of Sher-e-Kashmir University of Agricultural Science and Technology of Kashmir India was taken as a standard and rest of the samples were collected from various districts of the valley.The results revealed that the soil of the organic farm has significantly higher content of organic carbon (1.04%),available nitrogen, (298.7 kgha-1)phosphorus (16.72 kgha-1),potassium (296.30 kgha-1), dehydrogenase activity (68.7µg TPF/24 hr g-1 soil),total viable bacteria (78.90×106 cfu g-1 soil),fungi(48.73×103 cfu g-1 soil), actinomycete (27.20×103 cfu g-1 soil),phosphate solubilizing bacteria (18.30×105 cfu g-1 soil) and mycorrhizal spores (4.10 spores g-1soil) followed by that of district Kupwara rhizosphere soils with organic carbon (0.97%),available nitrogen (293.0 kg ha-1),phosphorus (15.81 kg ha-1),potassium (252.3 kg ha-1),dehydrogenase activity (62.7µg TPF/24 hr g-1 soil),total viable bacteria (72.60 ×106 cfu g-1 soil ),fungi (45.76×103 cfu g-1 soil), actinomycete (24.3 ×103 cfu g-1 soil),phosphate solubilizing bacteria (14.8×105 cfu g-1 soil) and mycorrhizal spores(3.8 spores g-1soil). Rhizobium bacteria were also isolated from the effective nodules of the bean plants grown at different places of various districts in kashmir valley,India.These isolates after identification were screened for the production of IAA,GA and siderophores.The isolate (Rhizobium phaseoli OF) from Organic farm was found most promising by producing 39.20 µl,162 µl, and 24µl of IAA,GA and siderophore respectively which was followed by 37.5 µl,153 µl,and 21µl of IAA,GA and siderophore respectively from the isolate obtained from rhizosphere soils of Kupwara district. The isolate (Rhizobium phaseoli OF) was used in combination with three levels of fertilizer nitrogen(0,20 and 40 kg ha-1 ) in a field experiment with beans as experimental crop and five replications by adopting RBD design to study the impact on various plant growth and yield attributing features such as number of pods per plant, pod weight and number of nodules. Nitrogen uptake,apparent nitrogen recovery and percent soil nitrogen utilization was also estimated.Maximum number of pods (12 plant-1) was recorded under the treatments T5 andT6.Significantly maximum pod weight (5.96 g) and number of nodules (60.45 plant-1) was observed under the treatment T5.Treatments T5 and T6 were at par with respect to nitrogen uptake in grains (63 and 64 kg ha -1),plant biomass (84 kg ha-1) and total N uptake (147 and 148 kg ha-1 ) by plant. Maximum apparent nitrogen recovery (210) and percent soil nitrogen utilization (46.37) was recorded from the treatment T5.From the present study it was concluded that the organic management is better option for sustaining the soil health and further the potential Rhizobium isolate may be mass multiplied and used on a large scale for harnessing its plant growth promoting potential.

Fluorescent pseudomonad bacteria were isolated from different strawberry fields in Srinagar and Baramulla districts of Kashmir, India. The isolates were compared with a standard isolate obtained from Biofertilizer Production Laboratory, Marathwarda Agricultural University, Parbani, Maharashtra, India, for various beneficial activities. Screening of the isolates showed that significantly higher IAA (36.08 µ mol ml-1) was produced by isolate PS8, siderophore, HCN and ammonia was produced by all barring PS3, PS7 and PS9. ACC deaminase activity was shown by PS1, PS7 and PS10. Significantly higher protease (516.12 µ mol ml-1), chitinase (6.8 µ mol ml-1) and pectinase (138.16 activity of Polygalacturanase unit ml-1) was exhibited by PS1.The isolate PS2 showed higher antagonistic potential against Fusarium sp. All the isolates except PS3, PS7, PS9 and PS16 solubilized insoluble phosphorus while as 17 isolates barring PS3, PS7 and PS9 solubilized zinc, iron and potassium.Statistically significant quantities 7.42 (µgml-1) and 60.35 (µgml-1) of sparingly soluble phosphate was solubilized by the isolate PS6 after 2 and 10 days of incubation respectively, simultaneously the pH of growing medium was reduced from 6.5 to 5.3 by the isolate PS6 after 10 days of incubation. All the isolates except PS7, PS11 and PS16 utilized eleven different sources of carbon and the numerical taxonomy of isolates depending on their carbon source utilization profile resulted into two major phenons at 0.27 similarity coefficient level.