Context- The country has faced at least 10 major invasive pest and weed attacks in the past 15 years, with most recent being the fall armyworm that destroyed almost the entire maize crop in 2018.

Impact of invasive species-

• Theirs is possibly the most unnoticeable of all invasions. When pests, weeds, viruses and bacteria invade, they can wipe out food crops, alter the ecology, deplete water levels and cause diseases. In the past 15 years, India has faced at least 10 major invasive pest and weed attacks
• .The most recent was the fall armyworm that destroyed almost the entire maize crop in the country in 2018. India had to import maize in 2019 due to the damage caused by the pest in 2018.
• Invasive pests and weeds can enter a country by flying over the border or by simply growing gratuitously. In such cases, checking their entry is difficult. But when they land up at airports and dockyards in cargos of imported grain or with items carried by tourists, the authorities should be able to weed them out.

Procedure of clearance in india- 

• Import of agricultural products is governed by the Destructive Insects and Pests Act, 1914. The country has 108 plant quarantine centres located at major airports, seaports and transborder railway stations. The check posts at these quarantine centres are under the control of the Central Board of Indirect Taxes and Customs (CBITC), which works in close coordination with Directorate of Plant Protection and Quarantine Storage (DPPQS)

• When an agricultural product arrives, customs officials check if it has a phytosanitary certificate or not. This certificate, showing that the product is without any pest or weed infestation, is issued by the government of the exporting country. If the product is certified, it is cleared by DPPQS after a sample test.

Issues-

1.  only 57, or only half of India’s plant quarantine centres, are functional. Rest are shut as the import-export is negligible or because of staff shortage.
2. Customs officials also often release the cargo without referring it to DPPQS
3.  In the 1990s the government had set the total number of sanctioned posts for DPPQS scientists at 1,928. This number has not increased since then. “What’s worse, about 60 per cent of the posts are vacant,” 
4.  corruption in DPPQS-

• The case came to limelight in 2007 after the US Department of Justice released a report stating that DOW AgroSciences, a US company, gave $0.2 million in bribes to India’s quarantine officials between 1996 and 2001 to get its products cleared at different ports in the country.
• More recently, in 2017, DPPQS transferred the entire staff of the Chennai regional plant quarantine station after CBI seized unaccounted money from officials on the charge of clearing consignments based on fake phytosanitary certificates. 
• Farmers and pisciculturists in India import barramundi seeds, breed the fish and export them. But the number of seeds often reduces after they are sent for quarantine checks. DPPQS officials declare that the seeds were found to be dead, but actually the seeds are stolen and illegally sold and cultivated

Need to strengthen Quarantine system

• With increasing global trade and movement, countries worldwide are becoming serious about alien pests and microbes. Nepal, for instance, stopped the entry of agriculture products from India without a phytosanitary certificate on June 17 after the outbreak of acute encephalitis syndrome in Bihar earlier this year.
• At a time when bioterrorism is a global reality, it is imperative that we get our quarantine system in order.
• There should be a war room-like cell to catalogue, monitor and investigate the influx of exotic pests and weeds

Directorate of Plant Protection and Quarantine Storage -

• Directorate of Plant Protection Quarantine & Storage was established in the year 1946 on the recommendation of Woodhead Commission as an apex organization for advising the Government of India and state governments on all the matter related to Plant Protection. The Directorate is headed by Plant Protection adviser. Plant Protection strategy and activities have significant importance in the overall crop production programmes for sustainable agriculture. Plant protection activities encompasses activities aimed to minimizing crop losses due to pests through integrated pest management, plant quarantine, regulation of pesticides, locust warning & control and training in desert areas besides training and capacity building in plant protection. It is an attached Office of Ministry of Agriculture and Farmers Welfare. 

Mandate

• To popularize adoption of integrated pest management (IPM) through training and demonstration in crops inter-alia promotion of biological control approaches in crop protection technology.
• To ensure availability of safer and effective pesticides through regulatory measures under the Insecticides Act, 1968.
• To prevent introduction of exotic pests inimical to Indian agriculture by implementation of Destructive Insects and Pests Act, 1914 supported by Plant Quarantine Order (Regulation of Import into India), 2003.
• To advise and assist the union government on all matters including international obligations related to plant protection.
• To keep watch and control over locust in scheduled desert area.
• Human resource development in plant protection technology.
• Monitoring pesticides’ residues at national level.

What Makes a Species "Invasive"?

• An invasive species can be any kind of living organism—an amphibian (like the cane toad), plant, insect, fish, fungus, bacteria, or even an organism’s seeds or eggs—that is not native to an ecosystem and causes harm. They can harm the environment, the economy, or even human health. Species that grow and reproduce quickly, and spread aggressively, with potential to cause harm, are given the label “invasive.”
• An invasive species does not have to come from another country. For example, lake trout are native to the Great Lakes, but are considered to be an invasive species in Yellowstone Lake in Wyoming because they compete with native cutthroat trout for habitat.

How Invasive Species Spread?

• Invasive species are primarily spread by human activities, often unintentionally. People, and the goods we use, travel around the world very quickly, and they often carry uninvited species with them. Ships can carry aquatic organisms in their ballast water, while smaller boats may carry them on their propellers. Insects can get into wood, shipping palettes, and crates that are shipped around the world. Some ornamental plants can escape into the wild and become invasive. And some invasive species are intentionally or accidentally released pets. For example, Burmese pythons are becoming a big problem in the Everglades.
• In addition, higher average temperatures and changes in rain and snow patterns caused by climate change will enable some invasive plant species—such as garlic mustard, kudzu, and purple loosestrife—to move into new areas. Insect pest infestations will be more severe as pests such as mountain pine beetle are able to take advantage of drought-weakened plants.