The Food and Agriculture Organization (FAO) of the United Nations estimates that up to 40% of food crops are lost due to plant pests and diseases annually. “Climate change, and human activities, have altered ecosystems, reducing biodiversity and creating new niches where pests can thrive. At the same time, international travel and trade has tripled in volume in the last decade and can quickly spread pests and diseases around the world causing great damage to native plants and the environment”, FAO says.

Invasive pests cost countries at least $70 billion annually and are one of the main drivers of biodiversity loss, estimated FAO’s June 2021 report “Scientific review of the impact of climate change on plant pests: A global challenge to prevent and mitigate plant-pest risks in agriculture, forestry and ecosystems”

The United Nations declared 2020 as the International Year of Plant Health (IYPH) to raise global awareness on how protecting plant health can help end hunger, reduce poverty, protect the environment, and boost economic development. The Year was extended until 1 July 2021 due to the postponement of some key initiatives caused by the COVID-19 pandemic.

Insects, diseases and weeds are the three main biological factors for losing crop yield and causing huge economic loss to farmers, according to a Study published in the journal, Crop Protection. Amongst these three, Weeds are the most notorious yield reducers leading to India losing an average of $11 billion each year in 10 major crops. In many cases, Weeds are found to be economically more harmful than insects, fungi or other crop pests said the study which used data from 1,581 farm trials in 18 Indian states, noted the study.

A July 2018 Knowledge Paper, published by industry body FICCI and advisory firm Tata Strategic Management Group, noted that farmers lose a significant part of their income as their crop and produce are attacked by pests and weeds. “India’s per hectare consumption of pesticides is significantly lower than countries with high yield. The per hectare consumption in India is 0.6 kg as compared to China’s 17 kg, Japan’s 12.5 kg,Germany’s 3.7 kg, France’s 3.7 kg and UK’s 2.8 kg,” revealed the Paper. “Therefore, the crops get affected by pests at various stages in the farming value chain including pre-harvest and during harvest. As the productivity is directly hampered due to pests and weeds, it affects the income levels of farmers. It is essential to protect not only the crop but also the produce as on an average 25% of the yield is destroyed during storage and transportation,” added the Paper.

According to the FICCI Paper, crop protection solutions play a vital role in two ways; protecting the crop and produce from pests and increasing the farm productivity. When judiciously applied, the damage of the crop is reduced and the output increases which directly impact the income generated per hectare. Hence, the crop protection industry will play a principal part in government’s aspiration to double farmer’s income by 2022, the Paper noted.

A study Increase in crop losses to insect pests in a warming climate published in the journal Science on August 31, 2018 says warmer climate will increase the metabolic rate of insects, which is the rate at which they digest what they eat. This will make them hungrier and so they will devour more crops causing more crop losses. Also, the rise in temperatures will lead to an increase in population of these pests.

The Government has announced in the Union Budget for 2022-23 that it will promote use of ‘Kisan Drones’ for crop assessment, digitization of land records, spraying of insecticides, and nutrients.

Prevention

The FICCI Knowledge Paper said several crop management features are designed to prevent outbreak of insects, diseases or weeds:

Location for Crops

Growing crops in locations where they are best suited to climate, soil and topography provides them with optimal conditions from the start. Appropriate land preparation builds on these conditions.

Selection of Crop variety

Choosing beneficial crop varieties, like those with disease and pest resistance, is the main feature of Integrated Pest Management. These varieties can be derived from traditional cross-breeding or modern biotechnology: pest-resistant and herbicide-tolerant varieties, for example, may reduce the need for other crop protection measures. Genetically Modified crops can also facilitate reduced or no-till practices, thus maintaining soil health and preventing erosion.

Crop Planting & Rotation

Planting similar crops alongside each other can substantially increase pests and should be avoided if possible. Traditionally, some farmers sow different crops in alternate rows or undersow a crop like maize with a legume such as cow pea to help improve soil fertility and reduce weeds. Such systems can help reduce pests.

Soil Management

Mechanical, physical and cultural crop protection methods prevent or minimize pests as well as reduce their build-up and carryover from one crop to another.

Water Management

Supplying water to crops is essential to plant health but it can greatly influence pest incidence and impact. Irrigation may be required, especially in dry areas or with crops that require a lot of moisture.

But while flood irrigating some crops, such as lowland rice, can control weeds, it is wasteful of water and can adversely affect beneficial soil organisms. Methods to combat these risks and conserve water include drip irrigation or growing crops on ridges or raised beds.