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Editorial – Insects as Allies

Albert Einstein once said that “if the bees disappeared, man would have only four years of life left” – a warning for an impending food problem if we neglected the natural pollinators. In fact it is not just about bees, but a whole lot of other living beings in the farm ecosystem that keep farming going.

The contribution of pollinators to the production of crops used directly for human food has been estimated at 153 billion Euros globally in 2005. This is about 9.5% of the total value of human food production worldwide.
Science Daily, 15th September, 2008

Insects and other arthropods, such as spiders and mites, are among the most common and diverse organisms in the environment. Over a million different species of insects have been described worldwide. While only a fewer than 1% of known insect species are considered to be pests, farmers anxious of reaping better harvests, try to kill insects the moment they are seen on the crop.

As predators, insects like lady bird beetles, hover flies, weaver ants, spiders etc., play a significant role in pest management. Parasitoids are very important to keep aphids, leaf miners, scales, mealy bugs and many other pests under control. Modern agricultural science has ripped farmers of their ability to distinguish between a pest and a beneficial insect.

Insects, as pollinators, decomposers and as natural enemies of crop pests provide a whole lot of ecological services to mankind. Most of the world’s crops depend on pollination by bees. The Food and Agriculture Organisation of the United Nations (FAO) estimates that out of some 100 crop species which provide 90% of food worldwide, 71 of these are bee-pollinated.

According to the Science Daily, the contribution of pollinators to the production of crops used directly for human food has been estimated at 153 billion Euros globally in 2005, which is about 9.5% of the total value of human food production worldwide. With declining crop diversity and loss of habitats, the numbers of pollinators is declining, affecting both quantity and quality of harvest. According to the scientists at the Indian Council of Agricultural Research, India needs minimum 7 million bee colonies just to pollinate 12 major crops. As against this we have about 1.2 million bee colonies in India.

Changing the way we farm

Monocultures and widespread use of chemicals to control pests has led to the destruction of many beneficial insects on farm. Practices like mixed cropping, crop rotations, cover cropping etc., will result in agricultural biodiversity. An abundance of insects, nematodes and micro-organisms play a key role in controlling agricultural pests and diseases. Even weeds in a cropping system help build up the population of natural enemies. (Holland, p.26) In many cases, weeds provide food and shelter for beneficial insects.

Parasitic wasps, for example, are attracted to certain weeds with small flowers. Field experience has shown that the number of predators attacking insects increases and the number of aphids and leafhoppers decreases on certain crops as the diversity of crops, including weeds (that act as host plants) increases. Research has shown that outbreaks of certain crop insect pests are more likely in weed-free fields.

Soils that are rich in organic matter harbours many beneficial insects. Practices which build the soil health need to be encouraged. Adams (p. 20) describes how a simple practice like using a mulch can help reduce soil moisture evaporation, while attracting a number of beneficial insects.

Its high time that the farmers move towards to an agro ecological approach from the high input, high efficient type of agriculture. Many studies show that insect pests tend to be less abundant and do less damage in fields which follow the agro-ecological principles. Rich and diverse flora within and around the farms serve as hosts to natural enemies of pests and build up their populations. More than 90 per cent of potential crop insect pests is controlled by natural enemies. And, for the failure to recognise this fact, we are paying heavily in terms of pest management costs.

Most institutions promote bee keeping as a cottage industry supplementing family income. This shows that the economic value is given more importance than the ecological value of honey bees. It is important to change this perception which requires special efforts. (Partap, p.5).

Understanding insects – Learning is the key

Adopting ecological agricultural methods requires an ecological understanding of insects – especially their biology and their interactions with plants, other organisms and their environment. An ecological understanding of insects can provide information on how they live and obtain resources, what life stages are especially vulnerable, what conditions affect the growth and decline of their populations, what roles they play in agricultural production systems, and how they respond to changes in the environment and to management practices.

Farmers Field Schools is an established and a proven methodology used by development agencies to bring about this understanding in farmers.(Krishnan J, p.17)

While some efforts are being taken up by individuals (eg., Shantha Veeriah, p.22), mainstream organizations (Mayfield and Belavadi, p.10) and CSOs (Krishnan J, p.17; Mathew and Leo, p.12 and Pastala and Krishnamoorthy, p.34) in educating farmers on the importance of an agro- ecosystem approach to farming, there exists a large need to upscale these efforts.

Building up the populations of these ‘friends’ of farmers is crucial for sustaining food production and thereby the planet. Lets recognize their role and hire them free of cost, for managing our crop production.