Vijay Singh Meena

Potassium as an Important Plant Nutrient in Sustainable Agriculture: A State of the Art

The current scenario of potassium (K) depletion in soil is slowly increasing due to K fixation or the unavailable form of K in soil. Presently, farmers are faced with a problem of higher price of K fertilizer or other fertilizers in market so farmers are unable to fulfill the demand of potassium in soil for plant growth. Potassium deficiency affects the nutritional quality, mechanical stability, and also pathogen resistance of crops. Therefore, that times needs to fallow the sustainable technology for sustainable agricultural production through use of microbial consortia of potassium-solubilizing microbes or biofertilizer/PGPR under organic farming system. The potassium-solubilizing microorganism is one of the best sustainable technologies, which solubilizes the fixed form of K available for plant uptake. Thus, the bio-formula of the potassium-solubilizing microorganism as biofertilizer offers environmentally sustainable approach and also fulfills the requirement of potassium for crop production.

Site-Specific Nutrient Management (SSNM): A Unique Approach Towards Maintaining Soil Health

Agricultural production in India has increased from ~50 Mt in 1950 to ~251 Mt in 2011–2012 by the intensive use of external inputs. The negative nutrient balance due to the imbalanced fertilization to the tune of ~8–10 Mt is reported, resulting in nutrient mining, stagnation and/or deceleration in productivity and soil health decline. The indispensable role of geo-informatics (RS, GPS and GIS) aided site-specific nutrient management (SSNM) for efficient use of resources and nutrients is suggested for achieving the projected food production target ~300 Mt by 2025. Towards the better response of SSNM over blanket fertilizer recommendation in terms of nutrient use efficiency (NUE), productivity and profitability is reported and discussed under Indian context. Long-term pooled data across several locations in India revealed an increase in yield of rice and wheat crops by ~12 and 17% and profitability by ~14 and 13%, respectively as an outcome of SSNM. Web based farmers’ advisory launched recently in the state of West Bengal is reported. The development of such dissemination mechanisms that consolidates the complex and knowledge-intensive SSNM information into simple delivery system is suggested for rapid implementation by the farmers towards maintaining soil health and ensuring future generation food security.

Potassium Solubilizing Microorganisms for Sustainable Agriculture

The potassium solubilizing microorganisms (KSMs) are a rhizospheric microorganism which solubilizes the insoluble potassium (K) to soluble forms of K for plant growth and yield. K-solubilization is carried out by a large number of saprophytic bacteria (Bacillus mucilaginosus, B. edaphicus, B. circulans, Acidothiobacillus ferrooxidans, Paenibacillus spp.) and fungal strains (Aspergillus spp. and Aspergillus terreus). Major amounts of K containing minerals (muscovite, orthoclase, biotite, feldspar, illite, mica) are present in the soil as a fixed form which is not directly taken up by the plant. Nowadays most of the farmers use injudicious application of chemical fertilizers for achieving maximum productivity. However, the KSMs are most important microorganisms for solubilizing fixed form of K in soil system. The KSMs are an indigenous rhizospheric microorganism which show effective interaction between soil-plant systems. The main mechanism of KSMs is acidolysis, chelation, exchange reactions, complexolysis and production of organic acid. According to the literature, currently negligible use of potassium fertilizer as chemical form has been recorded in agriculture for enhancing crop yield. Most of the farmers use only nitrogen and phosphorus and not the K fertilizer due to unawareness that the problem of K deficiency occurs in rhizospheric soils. The K fertilizer is also costly as compared to other chemical fertilizers

Combinatorial approaches for controlling pericarp browning in Litchi (Litchi chinensis) fruit

The availability of fruit like litchi has been limited by variability in yield, alternate bearing, seasonal differences and most commonly post harvest problems. The litchi fruit has a very short shelf-life during which red color turns brown which greatly affects the appeal to consumer although not the unique flavor. This review article focuses on the post harvest problems especially browning of litchi. The pericarp of litchi is also sensitive to desiccation and turns brown and brittle once moisture is reduced to half. A large number of approaches have been tried to solve this problem starting from hydro-cooling to gamma irradiation but single approach could not suffice for all. In modern era, the logical base of controlling browning is either to control the responsible enzyme or remove the undesirable product of enzyme catalyzed reaction. Thus enzyme technology with good postharvest practice can definitely solve this problem.

The Indian Himalayan Ecosystem as Source for Survival

The Indian Himalayan Region (IHR) covers ~95 districts of the Indian union, which starts from the foothills in the south (Siwalik); the region extends to the Tibetan Plateau in the north (trans-Himalaya). The IHR occupies the strategic position of the entire northern boundary (northwest to northeast) of the country and touches almost all the international borders of seven countries with India. The contribution of India is ~16 % of total geographical area, out of which ~17 % area is under permanent snow cover and ~35 % is under seasonal snow cover. The IHR is responsible for providing water to a large part of the Indian subcontinent and contains varied flora and fauna; it was estimated that ~40 million of the population reside in this region. The Indian Himalayan rivers run off ~1,600,000 million m 3 of water annually for drinking, irrigation, hydropower, etc. The IHR has been a potential source of important medicinal herbs and shrubs. This region is extremely rich in plant life and abounds in genetic diversity of all types of fauna and flora. The medicinal virtues of the northwest (NW) Himalayan plants are well known from the early times of the great epics of Ramayana and Mahabharata and are mentioned in the oldest Hindu scriptures, viz., Rigveda, which is said to be the source of the Ayurvedic medicine system. These high hills are the storehouse of numerous herbs and shrubs, which are exploited not only for the pharmaceutical industries worldwide. In fact, a large percentage of crude drugs in the Indian market come from this Himalayan region. Besides this, the Himalayan regions remain as a source of many cereal crops, pulses, vegetables, fruits, and animal husbandry. The climate change impact is at a global level, and this Himalayan region is no exception. Due to the climatic changes, a lot of disturbances happening like flooding, drought, wildfire, and other global changes derive from pollutions and overexploitation of resources. These changes drastically degrade our natural resources, and nowadays it challenges a need to adopt a comprehensive master plan for conservation of these resources for the survival in the future.

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.

Agriculturally Important Microbes for Sustainable Agriculture

Microorganisms that sustain the fertility of soils, resulting in improved plant nutrition, have continued to magnetize attention because of the increasing cost of agricultural inputs and some of their negative impacts on environmental sustainability. The continuous increase in the world population at an alarming rate requires more food for nutritional security. A doubling in global food demand projected for the next 50 years poses huge challenges for agricultural sustainability. Nowadays, plant growth is enhanced by the increasing input of agrochemicals, which act as plant growth regulators (PGRs) and as nutrients. Excessive/injudicious use of chemicals increases the chances of deteriorating soil and environmental quality. Rhizospheric plant growth–promoting microorganisms (PGPMs) are increasingly and promisingly being distributed in world agriculture. Meanwhile, current use of these efficient PGPMs may offer agronomic, pathogenic, and environmental benefits for intensive agricultural production systems. PGPMs are exhibiting a gradual increase in demand on the world market as sustainable and eco-friendly tools. Possible mechanisms for the effectiveness of biofertilizers are mobilization of the scarcely available plant nutrients nitrogen (N), fixer phosphorus (P), potassium (K), and zinc (Zn) solubilizers; production of plant growth–promoting substances; enhanced and induced resistance to environmental multistress factors; and direct or indirect suppression of harmful microbes. Research activities are currently limited by the lack of standards for production and quality control of different commercially used biofertilizers.

Climate Change Risk Perception, Adaptation and Mitigation Strategy: An Extension Outlook in Mountain Himalaya

Climate change is becoming an ever increasing global threat which is difficult to ignore. The major underlying cause is anthropogenic, i.e. excessive use of fossil fuels, destruction of forests for industrialisation and urbanisation with rapid overgrowing population. The danger is such alarming that ecosystem will be irreversibly altered which will lead to suffering of human life by many ways. The overriding appearance of climate change is the increasing average worldwide temperature which is popularly called as global warming, and as a consequence several regions of the Earth are facing visible problems such as melting of glaciers, sea level rising, deviations in precipitation patterns and increase in plant diseases, and a number of bourgeoning challenges for public health are coming across by many nations. According to the Intergovernmental Panel on Climate Change (IPCC) report, the Indian Himalayan ecosystem (IHE) is one of the extremely vulnerable zones followed by the coastal ecosystem towards the climate change in India, and as per projection the climate change will impart serious environmental, economic and social impacts of the Indian Himalaya agricultural production system. At this juncture, strong adaptation and mitigation strategy is needed for reducing the vulnerability of resource-poor hill farmers and sustainable development of the Himalayan ecosystem. Climate change adaptation involves holistic changes in agricultural and ecological management practices. It comprises a combination of distinct responses, the indigenous knowledge systems, alternative practices and accessible technologies. Adaptation policy should be taking into account the farmers’ perspective. In this piece of writing, the focus is to draw an outline of present condition and, furthermore, propose a strategy for effective adaptation and mitigation of climate change suited for Himalayan agricultural system.

Engineering plants for heavy metal stress tolerance

Plants are continuously exposed to abiotic environmental pressures. One of principal abiotic stress factors is heavy metal (HM), which as edaphic contaminants is noteworthy environmental hazard posing great negative impact on overall plants’ growth, metabolism and hence economic crop productivity and sustainability. During plants’ exposure to elevated HM stress, plants suffer from oxidative stress leading to changes in processes at molecular, biochemical, morpho-physiological and at whole levels. In high HM-contaminated soils, it is essential for plants to generate specific, appropriate protective/defensive mechanisms to nullify the toxic effects of these pollutants, for the normal growth and development. Plants are equipped with efficient strategies which enable them to uptake and accumulate the HMs in various parts or phytoremediate them into non-toxic forms from contaminated soils. Recent advancement in different disciplines of biosciences, such as genetic engineering, plant stress physiology, plant nutrition, transgenics, have aided us in the identification and characterization of compounds, transcription factors, gene products, exogenous phytoprotectants and segments of DNA which involve signal transduction cascades and stress-inducible proteins involved in HM detoxification and tolerance, however, underpinning various strategies for engineered heavy metal plant-stress tolerance is a topic of burning issue which remain least discussed. Taking into consideration several recent literature, the present paper (a) sheds light on the responses and impacts of various HMs to an array of plants’ physiological and cellular processes, (b) shows role of various underlying mechanisms behind tolerance or detoxification against specific metal/metalloid, and finally, (c) briefly highlights the possibility of obtaining transgenic improved HM stress tolerant crop plants which could clear the desks for engineering HM stress tolerance in plants for developing improved HM tolerant crop plants and challenging the heavy metal-induced threats to sustainable agricultural system and for qualitative and quantitative improvements in economic yield of crop plants.

Importance of Soil Microbes in Nutrient Use Efficiency and Sustainable Food Production

Microorganisms that sustain the fertility of soils, resulting in improved plant nutrition, have continued to magnetize attention because of the increasing cost of agricultural inputs and some of their negative impacts on environmental sustainability. The continuous increase in the world population at an alarming rate requires more food for nutritional security. A doubling in global food demand projected for the next 50 years poses huge challenges for agricultural sustainability. Nowadays, plant growth is enhanced by the increasing input of agrochemicals, which act as plant growth regulators (PGRs) and as nutrients. Excessive/injudicious use of chemicals increases the chances of deteriorating soil and environmental quality. Rhizospheric plant growth–promoting microorganisms (PGPMs) are increasingly and promisingly being distributed in world agriculture. Meanwhile, current use of these efficient PGPMs may offer agronomic, pathogenic, and environmental benefits for intensive agricultural production systems. PGPMs are exhibiting a gradual increase in demand on the world market as sustainable and eco-friendly tools. Possible mechanisms for the effectiveness of biofertilizers are mobilization of the scarcely available plant nutrients nitrogen (N), fixer phosphorus (P), potassium (K), and zinc (Zn) solubilizers; production of plant growth–promoting substances; enhanced and induced resistance to environmental multistress factors; and direct or indirect suppression of harmful microbes. Research activities are currently limited by the lack of standards for production and quality control of different commercially used biofertilizers.