Biotic Stresses

Biotic Stresses in agriculture

 
Biotic stresses influence adversely on agricultural productivity / profitability

Biological stresses affect metabolism of crops and livestock to reduce the expression of genes that are responsible for high yield of various agricultural commodities from agricultural crops and animals. As profitability of agriculture depends on productivity crops and animals at low production cost, the biotic stresses become impediments for cost management of seasonal cultivation of crops and also in livestock management.  The invasion of biotic stresses in crops is genetically controlled depending upon level of tolerance to pests (insect,mites, disease, nematodes) in their hosts. Such pests along with weeds and vertebrate pests such as rodents are major causes for crop yield reduction. In general, crops are lost to the tune of 25% due to insects, due to diseases including that of nematodes up to 20%, vertebrate pests including rodents about 6-8% etc.In large volume commodities, such loss in geographic areas would become enormous.

In general, pathogens and parasites cause diseases in animals. The loss in production of milk, meat and other animal products due to various biotic stresses could be to the tune of 35-46% worth about 1000 K Indian Rupee per annum. In the livestock and animal husbandry of the country, the loss estimates due to various biotic stresses range between 25 to 30 K Indian Rupee per annum.Added pressure is that global population is likely to reach 7 billion by 2025 and 10 billion by 2050. The demand for nutrition and food to human population in the country is to guide the market drive for stimulating agricultural production in farming. The agricultural production has to be increased from these lands that are under stress for both nutrition and organic carbon.

The research in biotic stress-tolerance in crops and animals has increasing importance, not only because agricultural production need to keep pace with increasing demand for agricultural produce from dwindling resources, but also due to possible changes in pest scenario with climate change that may make the environment much more hostile for agricultural production than what is experienced today. India has 33% irrigated land and 67% area is under rainfed / dryland crops and cultivation, where farmers are resource poor, and they are vulnerable to biotic stress. Poor access to tools and products of modern tool box of crop / animal health management shall be countering the aspired ambitions of profit from agriculture. While contingency planning is prepared and advised to farmers in the eventuality of failed monsoon and other weather aberrations, the farmers suffering from additional loss of crops and livestock due to pestilence and biotic factors need to be advised about the possible manner of saving his live assets in the farm.

Focused research on this important area in the National Agricultural Research System (NAARS) has been proposed through the ‘hub and spoke’ network and work on unresolved issues in biotic stress management in spite of progress in research in this direction.  The long term study of weather clearly states that there are changes in weather parameters so called “climate change”, which is very likely to aggravate the adverse impact of biotic stresses further. Therefore, there is an urgent need to take up coherent research plans to answer basic questions on modern agriculture influencing ecological process in agricultural farms in the country. Like-wise increasing CO2and greenhouse gasses in the atmosphere are possible reasons for increasing pest pressure and change in pest species community patterns to agricultural and horticultural crops. These factors are changing the pest scenario and there are great shift in pest dynamics.

The biotic stresses like weeds, insect, disease, nematodes, mites etc. are major /contributors to reduction of crop yield. Increasing industrialization could affect agricultural ecosystem by possible contamination of ground water and land with organic pollutant substances and heavy metals, in addition to possible bio-magnification through the vegetation of the region. Like-wise increasing ozone, CO2and greenhouse gasses in the farming atmosphere are possible reasons for increasing pest pressure and change in pest species community patterns to agricultural and horticultural crops. These factors are changing the pest scenario and there are great shift in pest dynamics and cycles.In the animal and fisheries sector, biotic stresses emerging out of parasitism and commensalism between microorganisms and higher facultative / obligatory organisms have taken toll in the productivity of commodities in the organized sectors for commercial exploitation from captive and natural production systems. Scientific tools and techniques would ease the stresses endured by animals (livestock, poultry, piggery, fisheries etc.) and shall provide better initiatives amongst entrepreneurial initiative. Commercial agriculture has to sustain farming system approach to offer profitability. Ventures and investments in agriculture shall shoot up if mitigation of biotic and abiotic stresses is contained and reduce the loss of agricultural commoditiesto acceptable levels.

Pesticides are chemical toxicants that are designed to check pest-build up when deployed at the identified dosage and time of application using the right applicator. However, in the excitement to enhance the production and commercial agriculture tended to ignore the natural balance of food chains and webs, the sudden spurt in pestilence became the order of the day. India adopted integrated pest management (IPM) as the policy drive to manage the various crop pests. The ideology of integration of all pest suppression tools in the IPM tool box brought in balanced approach to restore natural balance of food chains and webs in the agricultural farms. Today diseases such as potato late blight, rice blast sheath blight, wheat leaf spot and wheat rust are fairly contained due to intense breeding focus on developing tolerant crop varieties and other management tools. Similarly, the extensive cultivation of GM cotton could reduce the pestilence due to pod borer in pulses. Large-scale intensive break out of mites, aphids, jassids and other pests has been reduced due to combination of modern chemistry of pesticides that have environmental-friendly formulation chemistry. Such pesticides can be therapeutic and could enable restoration of natural agro-ecological food webs. Hence the upsurge of diseases and other pests did get suppressed to farmers’ advantage of reduced pestilence in farms. 

NIBSM would take up policy research in this direction and enable stakeholder-involvement for this purpose. NIBSM has the advocacy for responsible use of pesticides such as taking up good agricultural practice while using them that includes bringing in the safe handling and application in crops, safe transport and scientific destruction of pesticide containers and packing materials, rigidly following the type and nature of application of pesticides in crops is key to avoidance of potential risks that are anticipated from the use of pesticides in crops. Exploiting natural control systems has been one manner of undertaking biological control of biotic stresses in crops. Significant developments on the deployment of biocontrol agents as inundative pest suppression measure came into vogue in the second half of the last century. In the scheme of good agricultural practice (GAP), the role of such interventions has good leverage to sustain natural balance of organisms in agro-ecosystems. GAP policy for biotic stress management in crops, both annuals and perennials, need extensive strategisation. Structured and planned implementation in states under existing schemes of agriculture-development would favour better consumer acceptance of valued agricultural commodities.

Metabolic stresses on crop plants as well as physical damage to commodities due to the invasion of insects, disease, nematodes, larger animals such as rodents, weeds, etc. are threat to both crop production and productivity as well as for securing the commodities in the country from any form of loss. Similar stresses are encountered in other sectors such as in taking up animal husbandry and fisheries. There is a perceived drag in productivity due to biotic stresses in agriculture all over the world, as threatful challenge to the sustainable production of agricultural commodities. Indian agriculture is spread across more than fourteen agro-climatic regions and under each there are several sub-regions that have typical weather patterns and edaphic factors that guide the agricultural activities. Farmers have to adjust their judgement, every season, to decide upon commencing sowing of crops that are permitted by the agro-ecology and edaphic situation of the parcel of land they have to till. Crop production of field and horticultural crops are ridden with a host of pests and diseases both in the field as well as in storage of pre-processed commodities. Such crop loss, amounting to almost 30% all over the country shall endanger both food and nutritional security that is often called upon as national requirements. Similarly, the loss due to biotic stresses to live stock and fisheries is also noticed to be over 15%.

It is a fact that still farmers from remote parts of the country are unable to use various modern tools to manage biotic stress on their field, which creates more pressure to sustainability of resource poor, less knowledgeable farmers. Poor access to tools and products of modern tool box of crop / animal health management is retrogressive to ambitions of growth in agriculture.

 
Agricultural biosafety & biosecurity issues in Indian agriculture

The emerging issues on biosafety and biosecurity in agriculture, particularly in the light of emerging new pests as well as possible introduction of new pests (organisms that cause diseases, insects, mites etc.) could bear economic burden on Indian agriculture. Futuristic research in the management on emerging new pests could address certain aspects of agricultural biosecurity of the country. The NIBSM aspires to oversee both the funding and management of research in the areas of managing biotic stresses in agriculture. Invasive crop pests and animal diseases that enter through world-trade corridors as well as through porous / vulnerable land-locked borders have been threatful to the agricultural biosecurity of the country.

Consumer awareness on safety of agricultural commodities has been the perceived biosafety threat from the contamination of agro-chemicals, particularly those for pest management and nutrient supply to crops. Biosafety is connoted for various contexts of hazard-perception on biodiversity, risks on environment, animal and human health. The NIBSM propose to take up the risk assessment of agro-chemicals, Living modified organisms (LMOs) and other technological products and scientific tools.

NIBSM stands for sustaining the health of agriculture in totality through efficient crop, animal and human health as a trident.Indian agriculture went through the change-over during last century when the ‘Green-revolution era was ushered with intensification of agricultural input use towards maximisation of genetic yield of crops. The high yielding crop varieties / hybrids responded to increased agrochemical inputs such as chemical nutrients (fertilisers) along with he recommended farm yard manure quantities. However, this also triggered the upsurge in communities of herbivores from disease causing viruses, bacteria fungi, insects / mites and even big animals such as birds and other vertebrates (rodents, blue bull, wild boar etc.) that differentially exploited more nutritious crop tissues.

Biotic stresses that emanated from intensive agriculture were primarily due to anomalous mono-cropping of food crops. The crop husbandry practices with commercial scale production plan did upset the natural food chain and agri-biodiversity in the agro-ecologies. Unnatural practices drove the tendency for exploitation of natural resources. In comparison to dryland and rainfed agro-ecosystems, irrigated crop production ecologies were more ravaged by various biotic stresses. The avoidable crop loss in India is estimated to be about 18-20% due to all the above types of pests. Upsurge in pestilence has been in recent times was due to weather aberrations too.