Parthenium Control in Tamilnadu

– A Report by ‘c r e s k’“creating awareness”

14 August 2009


The highly noxious Parthenium weed has been declared a health hazard in several states of India. But not much of awareness is there in Tamilnadu to control this dangerous weed. This report discusses the dangers of Parthenium weed and some of the control mechanisms. We dedicate this report to the formers of Tamilnadu.


Parthenium is not native to India, but it has spread like wildfire across large swathes of both farm and waste land and now covers an estimated 35 million hectares across the country.


There is a reason for the weed’s evil reputation: When its seeds burst, they disperse fine pollen that spreads in the air and causes severe respiratory diseases in man as well as beast. Each parthenium plant grows thousands of these pollens that, when inhaled, clog the airways, nasal passages and lungs. It is one of the main causes of asthma in human beings, especially children, and cattle across India. In bovines, parthenium can cause a drastic drop in the milk produced.


The plant is so poisonous it can neither be used as animal fodder nor as biomass for fuel. When parthenium covers the land, its roots weaken the soil and farmers are left with depleted agricultural yields, which can fall by as much as 35-40 per cent.


India’s Union Ministry of Environment and Forests has allocated funds for research to eradicate parthenium. The challenge is that even herbicides don’t have too much of an impact on the weed, given its ability to flower in all seasons and reproduce rapidly. Attempts to pull the plants out by hand or to burn them results in the seeds bursting and releasing their dangerous pollen.


Even collecting the weed for lab research was hazardous. Parthenium causes not just asthma and other lung problems, but it also leads to severe skin infections and dermatitis. The only way to safely handle the plant is by wearing protective clothing.


A close examination of parthenium’s characteristics revealed that even its roots are polluting, killing nitrogen-fixing microbes and lowering the fertility of the soil. To make matters worse, the plant has a natural ability to rejuvenate itself.

They are deadly and come dressed in tight yellow-black jackets. No ordinary insect, this imported biological terminator -- Mexican Beetle -- packs in a lethal punch for the rouge weed parthenium.

Introduced in the Capital for field-testing, scientists are working at getting the public to work hand in glove with the `bug'. An effective biological control against the dangerous and unruly parthenium, the beetle introduced in various part of the country some time ago has brought the weed population under control without harming any other plant.

Parthenium is a dangerous imported weed that is poisonous, pernicious, allergic and aggressive and poses a serious threat to humans and livestock. So worried were scientist with the trouble caused by the weed that the National Research Centre for Weed Science has devoted an entire week to spread awareness about the weed in the Capital.

However, the problem with this weed-specific, slow-travelling beetle imported to India to deal with the wildly proliferating parthenium is that they are not able to cover large geographical areas as its host plant and are thus not being put to `maximum' use.

"Parthenium is abundant across the country and has no natural predators. Not eaten even by cattle, the plant chokes vegetation and is a health hazard to the people. While research is on at Dr. Ram Manohar Lohia Hospital and the All India Institute of Medical Sciences to come up with a cure for the allergy caused by the weed, little success has been achieved so far. The only way out is for people work with the National Research Centre For Weed Science to propagate and introduce the beetle to all areas that have a strong weed population, said director, National Research Centre For Weed Science, N.T. Yaduraju.

The Capital, which has a large population of the dangerous weed, is seeing an ascending index of health problems including dermatitis, asthma, and nasal-dermal and nasal bronchial types of diseases caused due to the weed. Scientists now claim that it is also eating into the `precious' bio-diversity of the area by not allowing naturally occurring vegetation around it.

Nearly 4.25 million hectares are under threat from the deadly weed parthenium, which, if controlled, can raise India’s crop yield substantially, a research body has said.

Scientists say that parthenium weed control could help increase crop yield and the country’s food grains production by 25-30 per cent.

Parthenium entered India with imported food grains in the mid-1950s.

“One of the world’s seven most devastating and hazardous weeds, Parthenium invaded 14.25 million hectares of farm land during 2001-07, compared to two million hectares in 1991-2000,” Jabalpur-based Directorate of Weed Science Research (DWSR) Director Jay. G. Varshney told PTI.

“Proper management of the weed could increase crop yield by 30 per cent and help us achieve self-sufficiency in import-dependent food items such as pulses and edible oil,” he said.

However, leading agri-scientist Prof. M.S. Swaminathan was surprised to learn that parthenium has spread to crop land as well. “I am surprised to know that parthenium has spread to farm lands. I have no knowledge about this development. So far I have seen it growing along roads and rail lines only,” he exclaimed.

Currently, total food grain production in the country is estimated to be around 227.88 million tonnes as per advance estimates of the Agriculture Ministry.

“There is no need to have a Rs. 4,882.5 crore National Food Security Mission if a control mechanism is put in place at a community level to manage the weed,” Varshney said.

The weed plant, also known as ‘congress grass’ and ‘gajar ghas’, is found abundantly in Andhra Pradesh, Karnataka, Madhya Pradesh, Maharashtra and Uttar Pradesh.

It spreads through the plant’s seeds, which are carried by wind, water, animals and humans. It is difficult to control its spread as the plant germinates exceedingly fast and a single plant can produce up to 25,000 seeds.

The weed has invaded millions of hectares across the country including crop land, wasteland and forest areas, according to DWSR, which is preparing a report on this.

Initially, the deadly weed occupied largely non-crop areas such as wasteland, open forests and roadsides. It has now spread to cropping land at an alarming rate, DWSR said. –PTI
What Is Parthenium?

Parthenium weed's botanical name is Parthenium Hystrophorous. It is a herbaceous plant, and a native of Tropical America. Parthenium weed is locally called Congress or Gajjar Grass. It is an annual herb and has a deep taproot and erect stem, which becomes woody with age. Parthenium weed leaves are deeply lobed. It is pale green in colour and has soft hair.
Parthenium weed flower is creamy white in color. The weed has a large number of stems. It has small (1-2mm long) black seeds with white scales. They are not visible to the naked eye. It has been declared noxious in America, Australia, India and many other countries especially those having tropical climates (Parson & Euthbert Son, 1992).
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Parthenium weed germinates in spring and summer. It dies around autumn. It can however; grow any time of the year, if conditions are suitable for its growth and usually grows near water points. It can set in four weeks after germination and flowering continues till the plant dies. It is a prolific producer of seed and can produce upto one-lac seeds per plant. In India, it exists virtually everywhere North, South, East or West.
Problems associated with Parthenium
It is a vigorous species, which colonizes in grassy land . It grows rapidly in bare areas along roadsides and water points.
It reduces the production of pasture.
It is very expensive to control.
It destroys price of grassy land.
It is a major health hazard to human beings.
It emits carbon dioxide and hence, poses a problem to nitrogen fixation and becomes a parasite, dependent on standing crops and animals in its vicinity.
Its pollens are a major cause of asthma, especially in children and elderly people.
It is a major cause of Allergic, Trinities Sinusitis, affecting about ten percent of the people who live near it (Tower & Subarao, 1992).
It is a major cause of dermatitis, a skin disease, among animals and human being.
It reduces yield of milk and weight of animals. 
It causes irritation to eyes.
Effect of Parthenium on human health and livestock
Contact dermatitis
Seasonal eruption of the exposed skin surface
Chronic lichensified eczema of the exposed skin surfaces
Eczematoid dermatitis
Skin eruptions and itching
Skin eruptions and itching
Allergic reaction
Cracks all over the sole
Allergic papules
Sore throat, bubbles in the mouth
General weakness, skin eruptions
Severe dermatitis
Loss of scalp, body hair, ridging on nails
Fever in cows
Inflamed udder and rashes
Hypersensitivity in rabbit
Restlessness, natural falling of hairs from the dorsal region of the neck and back, small boils and oozing of boils.
Ulcerations in buffaloes, horses donkeys, sheeps, and goats
Acute and chronic toxicity, ulcers both in the mouth and digestive tract, oesophagus and abnormal folds, necrosis of kidney and liver

It is a selective herbicide. It destroys only the Parthenium Weed without affecting the other plants, crops, vegetation in any way.
It destroys flowers, seeds and the leaves of the weed immediately.
Its reaction starts within 15 minutes of spraying. Complete process of decay occurs in 24 hours.
Cattle can graze on grass where the solution is sprayed. Our biochemical solution is non – toxic and safe for human beings and animals.
It prevents further growth of Parthenium Weed as its flowers and seeds are destroyed immediately after spraying.
It is extremely effective on barren land where chances of growth of this weed are substantial.
It has a well established safe profile. It does not need any specialized equipment or protection gear while spraying.
There is no residual effect on soil. This means that the growth of nutrient potential of the soil is not reduced.
It increases the value and utility of land once the terrible weed is destroyed.
It can be used at any stage of the life of the weed from spore to mature plant level.
Eradication of Parthenium weed
Parthenium Weed :
The other product developed is a unique by itself and is very good and useful agriculturally and medically also.
It is developed to eradicate the Congress Grass / American Grass popularly known as Gajar Ghaas in India. The botanical name is Parthenium Weed or Parthenium Hysterophorus. It is native to Tropical America. In India it is available in abundant. In 1965 during Congress Raj India had imported wheat from America. They had sent Red Wheat. The container carried the pollens / flowers of Parthenium Weed. As it came to India during Congress Raj it is called as Congress Grass in India.
Parthenium Weed is a vigorous species that colonizes in grazy land and it grows rapidly in brae areas along the roadside and watering points. Its presence reduces the pasture production. The control is very expensive on grazy land. If allowed to spread it becomes a serious and persistent problem. It is a major crop and pasture nuisance in Tropical Countries other than being a major health hazard to humans. Some of healths problems are for human as well as animals are as under.
It is an annual herb. It has a deep taproot and erect stem, which becomes woody with age. Its leaves are deeply lobed. It is pale green in colour and has soft hairs.
It gives out Carbon Dioxide throughout its life and hence can pose problem to Nitrogen fixation and become a parasite to standing crops and animals in proximity.
Pollen Stage : It is a major cause of Asthama (Allergic Bronchitis) especially in children playing outdoors. In adults and old age person’s severity increases due to environmental pollution due to growth of Parthenium Weed.
Respiratory problem upto 10% of people living in Parthenium Weed areas in India and Australia suffer from Allergic Rhinities Sinisitis.
Contact of plant causes Dermatitis (Skin Disease). This is a serious issue and the spread of the problem all over the body causes great discomfort. Dermatitis also affects animal with pronounced skin lesions.
Eye irritation to animals especially during grazing pasture. This results in reduction of milk yield and loss of weight of animal.
It germinates in spring and summer. It dies around autumn. It usually grows near water points. It can set in four weeks after germination. Its flowering continues the whole life. It’s a prolific producer of seeds and can produce upto one lakh seeds per plant.
                                  Fully Grown Parthenium                                    Spraying                                     Flowers turning yellow after Spray                5 minutes after Spray
              After 2 days                   No effect on other plants                   After 10 days


'Off-the-shelf' biocontrol for weeds in India

Developing a sustainable management strategy for Parthenium in India, focussing on biological control technologies

Validated RNRRS Output.


Research paper

Eucalypt oils for the control of Parthenium (Parthenium hysterophorus L.)

R. K. Kohli, Daizy R. Batish and H. P. Singh

Department of Botany, Panjab University, Chandigarh-160 014, India


Videos in managing Parthenium:


Biological Diversity


Report Compiled by ‘c r e s k’