Shrinking per capita arable land, surging population, and rising demands are posing a big challenge of the millennium — producing more food to feed the people while safeguarding the environment at the same time. Climate change is increasingly leading to frequent and unexpected environmental fluctuations globally. Productivity and resilience in agriculture are the topmost priorities of Government of India and it plans to focus on climate-resilient agriculture through resilient crop varieties as well as introduce farmers to natural farming. The excessive usage of chemical agri-inputs has led to degraded soil health, reduced soil fertility and deteriorated soil quality globally (1/3rd of world’s soil is degraded as per FAO, 2015). This has led to declined productivity and pushed the world into food insecurity for its ever-growing population. Due to cascading issues like climate change and related environmental concerns, food supply will fall by 12 per cent over the next 25 years, triggering a 30 per cent increase in the prices of food. On one hand, healthy soil can provide balanced nutrients to plants, essential for good crop production but soils are becoming depleted in carbon content, ground water polluted with nitrates, along with increased nitrous oxide and methane emissions into the air. With the natural resource base getting depleted and degraded, major disruptions in food and its production system will, without doubt, force the agricultural system to change.

Natural Microbiomes vs Chemical Fertilizers

The soil rhizosphere is ‘home’ to several microbiomes containing a functional network of microbes, many of which are responsible for various traits and features exhibited by plants. There are multipronged impacts of bio-prospected, functional microbiomes not only on the soil rhizosphere but they also balance plant nutrition and soil properties over a period of time. Microbes of the rhizosphere microbiome interact in multiple ways to improve plant growth and offer potential to increase crop resilience in climatic fluctuations especially those related to nutrients and water. The impact of microbes on nutrient dynamics, carbon cycling, soil health and stress tolerance of plants contributes to the development of sustainable ecosystems along with positive impacts on the soil microflora and their deployment towards the roots. Hence, functional microbiomes can provide multiple benefits to soil and plant health and the response to changing climates and extreme weather challenges faced by our farmers can also be mitigated largely.

These microbiomes can then be tailored to guide the transition towards a more sustainable and resilient agriculture, decrease farming costs, improve crop yields, inform agricultural policies and help achieve reductions in fertilizer usage. This will further help enhance farmers’ additional income.

Indiscriminate Use of Chemical Fertilizers Deteriorating Soil

Highly-subsidized chemical fertilizers are being used indiscriminately on majority of dead or dying Indian soils to provide more nutrients to the growing crops. However, crop production is not increasing due to the soil quality deteriorating rapidly. A shift in subsidy from fertilizer to nutrients is needed so that there can be a balance of nutrients in the soil that help in tying up carbon to the soil. To ensure sustainable agricultural practices, the Indian government is trying to encourage Zero Budget Natural Farming (ZBNF) with a view to decrease the input costs, improved crop yields, and thereby enhancing sustainability and efficiency of agriculture while supplementing farmers’ incomes. The government has introduced various schemes, such as PM-PRANAM, to encourage biofertilizer manufacturers take several initiatives to fast track the adoption of bio-fertilizers into farming practices to bring about a shift from conventional to regenerative/organic farming practices. This involves the usage of mycorrhiza and bacterial bio-fertilizers. Keeping in mind that natural microbial relationships provide added benefits as compared to pure microbial cultures; microbiome-based bio-formulations must be put to use along with chemical agri-inputs due to the extended benefits they provide for crop growth, soil and the environment. All in all, a combination of chemical and biological agri-inputs can provide a win-win situation for all. This is a disruptive strategy which will significantly impact crop production, soil quality and health.

The integration of ecology with microbiological, molecular, and functional approaches allows to propose solutions to make agricultural production more resilient to environmental stresses. It will also enable the development of economical, edaphoclimatically stable bio-formulations to address environmental challenges faced by farmers while conserving the natural microbial biodiversity of soil at the
same time.

We are at crossroads with a choice between doing nothing, risking future food security and health, or deciding to act, by radically altering our food production practices from a sustainable and bio-economical perspective. The utilization of soil microbiomes could accommodate the necessary surge in agricultural production, without continuing to degrade our natural resource base.

Natural Agri-Inputs: A Sensible Alternative

Given the rising global demand for food and the current rate of soil nutrient extraction, exacerbated by the increasing use and decreasing worldwide supply, there is a dire need for a sustainable alternative that helps meet various UN SDGs. Mycorrhizal fungi and soil microbiomes can significantly improve the soil quality, while solubilizing and enhancing phosphorus (as well as other essential micronutrients) uptake could be a very effective approach to overcome soil degradation amid nutrient-deficiency crisis. This would also suffice to fix nitrogen in soil and sequester carbon along with enriching the soil microbiota, enhancing crop productivity, water use efficiency, and the biodiversity of the site. Additional benefits include diversifying farmers’ risks, reducing their costs, albeit enhancing the food nutrition security of the country. #

Dr Mandira Kochar works as Senior Fellow at Sustainable Agriculture division, TERI; and Dr Vatsala Koul works as Associate Fellow at Sustainable Agriculture division, TERI.