By Muhammad Bello Mustapha
ABSTRACT: Agriculture have a significant portion of the economies of the world and therefore can contribute toward a major continental priorities such as eradicating poverty, hunger, rapid industrialization, economic diversification, sustainable Resource utilization, investments, and environmental management. Plant-associated micro biomes have tremendous potential to Improving plant resilience and yields in farming systems. Agriculture as bio-fertilizers, bio-pesticides, bio-herbicides, bio-insecticides, fungal based bio-insecticides and viral based bio insecticides. An intensive agricultural production is necessary to satisfy food requirements for the growing world population. However, its realization is associated with the mass consumption of non-renewable natural resources and with the emission of greenhouse gases causing climate changes. This research is meant to meet sustainable environmental and economic issues without compromising yields. In this context, exploiting the agro ecosystem services of soil microbial communities appears as a promising effective approach.
KEYWORDS: Sustainable Agriculture, Bio-Fertilizers, Bio-Pesticides, Bio-Herbicides, Environmental Health.
INTRODUCTION
The need for chemical free agricultural practices is becoming eminent due to the effects of these chemicals on the environment and human health. As countries develop, People are also demanding more and better food. These pressures are multiplied by shrinking farmlands, rising labor costs and shortage of farm workers. Conventional intensive agricultural practices that depend on inorganic fertilizers, pesticides and other chemical inputs have increased yield but also contributed to soil degradation, loss of biodiversity, Increased susceptibility of crops to pests/pathogens and negative environmental impacts which together have a significant consequences for human health and food security. In addition to structural decline in farm productivity in many countries, major challenges in developing Countries lie in substantially increasing yield quality and quantity, without further increase in farming costs and detrimental environmental impacts. The potential benefits of microbiology are numerous and include providing resistance to crop pests, increasing crop Yield and reducing chemical pesticide usage. Agricultural technologies that ensured a green revolution in the middle of the 20th century, causing now high ecological cost and contributing to global pollution, unfavorable climate change and loss of biodiversity. Microbes in sustainable agriculture is due to the genetic dependency of plants on the beneficial functions provided by symbiotic co-habitants. Therefore, microbial Biotechnology and its applications in sustainable Development of agriculture and environmental health are getting better attention. Interest in the microbial Biodegradation of pollutants has intensified in recent years as Mankind strives to find sustainable ways to clean up contaminated environments. In agriculture, what farmers want in their crops are Traits such as high yield, disease resistance, pest resistance, and quality such as higher nutrients, color, texture, and taste. Agriculture in many parts of the world is undergoing a major strategic restructuring to achieve vertical integration between production and utilization. Genetic engineering is creating a revolution in agriculture, allowing an ever-increasing range of plants and animals. Production hope to use recombinant technology to Improve productivity of plants and animals important to Agriculture. Agricultural microbiology is presented as a Synthetic research field responsible for knowledge transfer from general microbiology and microbial ecology to the agricultural biotechnology. A fundamental knowledge of the genetics, molecular biology, ecology, and evolution of symbiotic interactions could enable the development of microbe-based sustainable agriculture.
MICROBIAL INTERVENTION
It is the action or process of intervening biological processes in soil or in plants/plant roots by the microorganisms present in the rhizosphere which is mostly beneficial for enhancement of nutrient availability as well as growth and yield of crops. microbial intervention may be helpful in attaining higher productivity with sustainability in agriculture in many ways, like: fixation of atmospheric nitrogen, increased availability of plant nutrients, decomposition and recycling of organic wastes and residues, bioaccumulation or microbial leaching of inorganics (Brierley 1985; Ehrlich 1990), suppression of soil-borne pathogens, bio-degradation of toxicants including pesticides, production of antibiotics and other bioactive compounds, production of simple organic molecules for plant uptake, Complexation of heavy metals to limit plant uptake and solubilization of nutrient sources. Further, in order to improve microbial defense in soil, few steps can be followed:
1. Soil and plant tonic containing a broad diversity of beneficial and predatory microbes, which is an effective way to build-up microbial numbers and diversity are used.
2. Bio foods and stimulants can also be added, which provides food and stimulation for beneficial soil microbes to build and strengthen the population once they are introduced.
3. Maintaining good levels of organic carbon will also provide a favorable habitat for beneficial microbes and encourage their proliferation and survival.
Soil microbes can also help in degradation and detoxification of harmful active ingredients of pesticides applied in various crops as well as activation of putatively pesticide organo-molecules. Heterotrophic microbes generally tend to derive energy from the carbon molecules of these compounds and thus trigger their activation or deactivations in general.
ROLE OF PLANT GROWTH PROMOTING RHIZOBACTERIA AS A BIOFERTILIZER:
Organic farming is gaining attention due to uprising demand of green synthesis. Bio fertilizers are a substitute for chemical fertilizers and can be defined as tiny microorganisms which are applied to seeds, plants or soil so to enhance the plant growth by increasing the concentration of free nutrients in the soil which can be readily available to plants (Vessey, 2003). According to Mishra et al., [2013], a blend of live or latent cells accelerating global processes like nitrogen fixation, phosphate solubilization, mineralization, and are applied to soil, seeds, roots or composting area are termed as bio fertilizers. A similar definition was given by Malusá and Vassilev [2014], stating bio fertilizer as a formulated product having one or more microorganism and aimed to upgrade the nutrient status by either making them readily available to plantS or by increasing access to nutrients by plants. Bacteria, algae and fungi are potential bio fertilizers and are grouped in two categories one is nitrogen fixers like Rhizobium, Azotobacter, Azospirillum, Acetobacter, Blue-reen Algae, Azolla, and phosphorous solubilizers / mobilizers like Mycorrhizae. Few more categories have been identified recently, the potash mobilizers like Frateuria aurentia, Zinc & Sulphur solubilizers like Thiobacillus species and manganese solubilizer fungal culture like Penicillium citrinum. These new strains would also address the issue of Fertilizer Use Efficiency‟ and would also enhance the efficacy of Bio-fertilizers (Mishra et al. 2013). Major benefits gained from these microbes includes increased recycling, mineralization and uptake of nutrients such as atmospheric nitrogen fixation, solubilization of phosphorus and potassium, synthesis of siderophores for iron sequestration, synthesis of vitamins, amino acids and plant growth regulating substances like auxins and gibberellins that cause elongation of root and shoot leading to improved plant growth (Glick, 1995).
Moreover, these bacteria are able to feed upon contaminants like heavy metal, pesticides and reduces their concentration by microbial degradation and uptake of pollutants by plants. Furthermore, they reduce the number of pathogens either by competition or by producing action via antibiotics, siderophores and/or hydrolytic enzymes (Saharan & Nehra, 2011). Bio fertilizer is a rapid growing industry as it is ecofriendly, cost effective, enhances crop production and soil sustainability. The functioning of bio fertilizer is relatively easy to understand, they are applied as seed or soil inoculant after which they colonize and helps in nutrient cycling and crop productivity. Around, 60% to 90% of the total applied fertilizer is lost and the remaining 10% to 40% is reserved by plants. In this regard, microbial inoculants have paramount significance in integrated nutrient management systems to sustainable agricultural productivity and healthy environment (Bhardwaj et al. 2014).
CONCLUSION.
Keeping in mind all these beneficial roles of microorganisms present in soil rhizosphere, it can be concluded that plant growth promoting rhizobacteria is the most promising way for green synthesis and sustainable way of enhancing productivity, disease resistance and maintaining ecological balance.
REFERENCE
Bhardwaj, D., Ansari, M. W., Sahoo, R. K. and Tuteja, N. (2014). Bio fertilizers function as key player in sustainable agriculture by improving soil fertility, plant tolerance and crop productivity. Microbial Cell Factories, 13, 66.
International Journal of Scientific and Research Publications, Volume 10, Issue 10, October 2020. ISSN 2250-3153
Ahmad, F., Ahmad, I. and Khan, M.S. (2008). Screening of free-living rhizospheric bacteria for their multiple plant growth promoting activities. Microbiol. Res. 163, 173181.
Muhammad Bello Mustapha from Department of Science Laboratory Technology, Federal Polytechnich Bali, Taraba State
