India to introduce Mexican beetles to control congress grass

The Punjab Agricultural Department here has decided to introduce beetles to organically counter the growth of parthenium weed, commonly known as congress grass or carrot grass, while reducing pesticide use.

 

The department called in experts from the Directorate of Weed Science Research (DWSR) in Jabalpur, Madhya Pradesh, to demonstrate the technique to the farmers in the region.

 

A two-day training programme was held on August 28 and 29 at the agricultural department here.

 

In May, the Punjab government had declared the Congress grass as a ‘noxious weed’ under the provisions of ‘The East Punjab Agricultural Pests, Diseases and Noxious Weeds Act, 1949’, citing threat to the ecosystem. The government also made it mandatory for land owners to adopt measures to control its infestation, by December 31, 2015.

 

DWSR principal scientist Dr Sushil Kumar said congress grass can be controlled with the help of bio-agents which feed on the weed. “Mexican beetles (scientific name Zygogramma bicolorata Pallister) feed on congress grass. They are imported from Mexico, where parthenium was first spotted,” said Kumar.

 

He added this technique had been implemented with success in Bihar, Uttar Pradesh and Madhya Pradesh. The weed is known to cause skin eruptions, itching, allergy and respiratory troubles in humans and animals, apart from affecting crop productivity.

 

An adult beetle can defoliate a parthenium plant in six to eight weeks. These beetles are capable of multiplying rapidly, and releasing 500-1,000 beetles in a controlled manner can eventually control growth of congress grass.

 

“These insects have life span of 28-30 days and they migrate to adjacent areas once they exhaust the feed at the spot where they were released,” said Kumar. While adults attack the main plant, larvae feed on softer leaves, he said. “Biological control is inexpensive and it poses no threat to non-target organisms, environment and biodiversity.

 

Using this measure, farmers can avoid the use of life threatening and expensive pesticides,” he pointed out.

 

Chief agriculture officer Inderpal Singh Sandhu said the method would not harm the other crops in the field. “Other crops will not be harmed as they cannot survive on anything except Congress grass. This is the first time in Punjab that we will be using this economical technique,” said Sandhu.

 

Meanwhile, DWSR officials gave the agriculture department around 25,000 beetles for a pilot project in nearby areas.