Jaideep Kumar Bisht

Phosphate solubilization and growth promotion by Pseudomonas fragi CS11RH1 (MTCC 8984), a psychrotolerant bacterium isolated from a high altitude Himalayan rhizosphere

Phosphate solubilization and growth promotion by Pseudomonas fragi CS11RH1 (MTCC 8984), a psychrotolerant bacterium isolated from a high altitude garlic rhizosphere from the Indian Himalayas, are reported here. The identity of the isolate was arrived on the basis of its biochemical features and sequencing of the 16S rRNA gene. The isolate grew and solubilized phosphate at temperatures ranging from 4 to 30°C. Besides solubilizing P it produced indole acetic acid (IAA) and hydrogen cyanide (HCN). Seed bacterization with the isolate significantly increased the percent germination, rate of germination, plant biomass and nutrient uptake of wheat seedlings. While Pseudomonas fragi is normally associated with the spoilage of dairy products stored at cold temperatures, this is an early report on the plant growth promoting ability of the bacterium.

Characterisation of a psychrotolerant plant growth promotingPseudomonas sp. strain PGERs17 (MTCC 9000) isolated from North Western Indian Himalayas

A psychrotolerant, Gram negative, rod shaped, plant growth promoting bacterium (PGPB) was isolated from high altitude of North Western Indian Himalayas. The identity of the bacterium was confirmed by morphological, biochemical and sequencing of the 16S rRNA gene. The sequence analysis revealed maximum similarity withPseudomonas vancouverensis. It exhibited tolerance to a wide pH range (5–12; optimum 7.0) and salt concentrations up to 5% (w/v). The isolate produced 8.33 and 1.38 μg/ml of IAA at 15°C and 4°C respectively, on the third day after incubation. It solubilised 42.3, 66.3 and 74.1 μg/ml of tricalcium phosphate at 4, 15 and 28°C respectively after seven days of incubation. The strain also possessed HCN and siderophore production abilities at 4°C. It exhibited inhibitory activity against several phytopathogenic fungi in three different bioassays. The maximum relative growth inhibition was recorded againstSclerotium rolfsii andRhizoctonia solani (100%), followed byPythium sp. (73.1%) andFusarium oxysporum (19.7%), in volatile compound assays. Seed bacterization with the isolate enhanced the germination of wheat seedlings grown at 18±1°C by 20.3%. Bacterized seeds also recorded 30.2 and 27.5% higher root and shoot length respectively, compared to uninoculated controls.

Isolation, molecular characterization and growth-promotion activities of a cold tolerant bacterium Pseudomonas sp. NARs9 (MTCC9002) from the Indian Himalayas

A bacterium that grows and expresses plant growth promotion traits at 4 degrees C was isolated from the rhizospheric soil of Amaranth, cultivated at a high altitude location in the North Western Indian Himalayas. The isolate was Gram negative and the cells appeared as rods (2.91 x 0.71 microm in size). It grew at temperatures ranging from 4 to 30 degrees C, with a growth optimum at 28 degrees C. It exhibited tolerance to a wide pH range (5-10; optimum 8.0) and salt concentrations up to 6% (wt/vol). Although it was sensitive to Rifampicin (R 20 microg mi-1), Gentamicin (G 3 microg mi-1), and Streptomycin (S 5 microg mi-1), it showed resistance to higher concentrations of Ampicillin (A 500 microg mi-1), Penicillin (P 300 microg mi-1), Polymixin B sulphate (Pb 100 microg mi-1) and Chloramphenicol (C 200 microg mi-1). The 16S rRNA sequence analysis revealed maximum identity with Pseudomonas lurida. The bacterium produced indole Acetic Acid (IAA) and solubilizes phosphate at 4, 15 and 28 degrees C. It also retained its ability to produce rhamnolipids and siderophores at 15 degrees C. Seed bacterization with the isolate enhanced the germination, shoot and root lengths of thirty-day-old wheat seedlings by 19.2, 30.0 & 22.9% respectively, as compared to the un-inoculated controls.

COINOCULATION OF RHIZOBIUM LEGUMINOSARUM-PR1 WITH A COLD TOLERANT PSEUDOMONAS SP. IMPROVES IRON ACQUISITION, NUTRIENT UPTAKE AND GROWTH OF FIELD PEA (PISUM SATIVUM L.)

The effect of a cold tolerant Pseudomonas sp. Strain, PGERs17, on nodulation, iron acquisition and nutrient uptake of field pea (Pisum sativum L. variety VL Matar 42) seedling was determined on the basis of iron acquisition and growth promotion, chlorophyll content, physiologically available iron, Leghaemoglobin from nodules, nitrogen (N) uptake, phosphorus (P) uptake, potassium (K) uptake, iron (Fe), and zinc (Zn) uptake of shoots. Coinoculation of PGERs17 with Rhizobium leguminosarum-PR1 significantly (P > 0.05) increased nodulation (156.2%) and 57.1% higher plant biomass. Coinoculation enhanced total chlorophyll content (31.5%), physiologically available iron (106.7%), total iron (95.9%) and 17.5-fold higher leghaemoglobin concentration in root nodules over uninoculated control plants. Coinoculation also enhance N uptake (66.3%), P uptake (23.3%), K uptake (47.1%), and 2.75-fold higher Zn uptake of shoots compare with uninoculated control. Hence, cold tolerant Pseudomonas sp. strain PGERs17 can be employed as a bioinoculant along with Rhizobium leguminosarum-PR1 to enhance plant growth, iron acquisition and nutrient uptake of field pea enhance plant growth, iron acquisition and nutrient uptake of field pea seedlings at cold temperature conditions.

Cold-Tolerant PGPRs as Bioinoculants for Stress Management

Cold stress is a major environmental constraint to plant productivity. Cold-induced losses in yield probably exceed those from all other causes, since both the severity and duration of the stress are critical. Plants have evolved special mechanisms to overcome the life-endangering influence of low temperature and to survive freezing. Plant-growth-promoting rhizobacteria (PGPRs) have a high potential in agriculture because they can improve plant growth, especially under limiting or stress (cold/chilling) conditions. The agricultural importance of cold-tolerant microbes stems from the fact that the world over temperate agro-ecosystems is characterized by low temperatures and short growing seasons that subject both plant and microbial life to cold-temperature induced stress. Hence, there is a need to identify a group of potential PGPRs that could retain their functional traits under cold (low)-temperature conditions. Such microbes can be profitably used as bioinoculants in agricultural production systems in the temperate regions of the world. This chapter deals with the effect of temperature on plants and management of cold stress by using cold-tolerant PGPRs in improving soil quality and productivity of agricultural crops.

Cold-Tolerant Agriculturally Important Microorganisms

Cold-tolerant microorganisms are endowed with the ability to grow at 0°C, though their growth optima lie in the mesophilic range. To overcome the stress induced by low temperatures they have evolved a variety of adaptive responses at the cellular and molecular levels. Multiple cell membrane modifications ensure that solute transport is not impaired at low temperatures. Other mechanisms include the synthesis of cold-shock proteins (Csps), cold acclimation proteins (Caps), cryoprotectants, ice nucleation factors, cold-adapted enzymes, and RNA degradosomes. The agricultural importance of such microbes stems from the fact that the world over temperate agro-ecosystems are characterized by low temperatures and short growing seasons that subject both plant and microbial life to cold temperature induced stress. Hence, there is a need to identify potential microbes that retain their functional traits under low temperature conditions. Such microbes can be profitably used as inoculants in agricultural production systems in the temperate regions of the world. This chapter deals with the cold tolerance/resistance mechanisms operating in microorganisms and the utility of cold-tolerant microbes in improving soil quality and productivity of agricultural crops.

Optimization of Farmyard Manure to Substitute Mineral Fertilizer for Sustainable Productivity and Higher Carbon Sequestration Potential and Profitability under Gardenpea-French Bean Cropping System in the Indian Himalayas

Carbon sequestration potential (CSP) and sustainability of gardenpea-french bean cropping system was assessed with farmyard manure (FYM) application vis-à-vis mineral fertilization as recommended NPK (NPK) and integrated nutrient management practices (INM) after six years’ cropping in Indian Himalayas. Application of 20 tons FYM ha−1 provided highest CSP (0.527 Mg C ha−1 year−1) in soil and sustainability index. With the help of quadratic equations, it was estimated that maximum profit (optimum yield) and turn over of invested money could be achieved with application of 20.0 and 15.6 t FYM ha−1, respectively. Application of 5.9 and 8.9 tons FYM ha−1 would substitute NPK and INM, respectively. Pod number plant−1 was the most important yield-contributing attribute as found from principal component analysis. Pod yield could be modelled through multiple linear equation with help of yield attributes.

Socioeconomics and sources of livelihood security in Central Himalaya, India: a case study

ABSTRACT This case study was conducted in Himalayan watershed to understand traditional farming and socio-economic status of the people in Kumaon Himalaya, Uttarakhand, India. In spite of high literacy rate in this area, their livelihood security is reliant on traditional farming practices that include agroforestry beside forest produce. More than 85% farming is rainfed and managed in a traditional way. Land holding size owned by farmers in the area extended from 0.57 to 2.57 ha but majority of farmers (51–80%) had farms of size less than 0.50 ha. The study revealed that forests provided 73–79% of required energy from fuelwood and more than 81% fodder. Agroforestry, livestock (dairy and poultry/goat rearing) and labour employment are the major sources of income to the people in the watershed. The income of people was positively correlated with livestock rearing and traditional farming.

Toward the C Sequestration Potential of Agroforestry Practices to Combat Climate Change in Kumaon Himalaya, India

The Himalayan region has a long tradition of tree-based smallholder agroforestry practices, which are rich in the different species of trees. Several indigenous agroforestry systems based on people’s needs and site-specific characteristics have been developed over the years by the smallholders for various uses. These agroforestry practices have attractive, wide, and promising potential to store carbon (C) and remove atmospheric carbon dioxide (CO2) through enhanced growth and development of trees. From the recent study results reported as the maximum biomass (1,170 Mg ha−1), C stock (526.5 Mg ha−1), and biomass C equivalent CO2 (1,932.2 Mg ha−1) was found in high density of oak plantation, followed by pecan nut-based agrihorticulture system biomass (48.7 Mg ha−1), C stock (21.9 Mg ha−1), and biomass C equivalent CO2 (80.0 Mg ha−1). However, minimum biomass (8.6–28.4 Mg ha−1), C stock (3.8–12.7 Mg ha−1), and biomass C equivalent CO2 (13.9–46.6 Mg ha−1) reported in fruit tree-based agrihorticulture system. The C storage in plant biomass is only feasible in abovementioned type of perennial agroforestry systems, and smallholder farmers are the real practitioner of these agroforestry systems. Thus, agroforestry systems are not only remunerative to the farmers from livelihood point of view but also contributing toward trapping of atmospheric CO2 vis-a-vis mitigation of climate change.

Conservation Agriculture and Climate Change: An Overview

Conservation agriculture (CA) is the integrated management of the available natural resources such as soil, water, flora, and fauna with partial outside inputs which increases the efficiency of natural resource use. It provides sustainability in farming production through maintaining the quality of natural resources by stable or semi-stable organic cover to soil. Zero or minimum tillage or no-till (NT) and minimum disturbance of soil along with varying rotation of crops are a must for future prospects. CA is an integrated approach to agriculture cultivation that helps enhance food security, allay poverty, conserve biological diversity, and preserve ecosystem services. CA practices are also helpful in making farming systems more resilient to recent climatic changes. CA can comprise wide-ranging practices such as management of forage and farm animals, fallows improvement, combined cultivation of agricultural crops and trees as agroforestry, management of watershed, and management of areas which are reserved for village and community people. In this chapter, climate change predictions for Indian Himalayan Region (IHR) will be discussed. Then the potential of CA as a source to alleviate and acclimatize to climate change will be examined for climatically affected environments.