Biological based integrated Congress grass management in NE India

Prof N Irabanta Singh *

Parthenium hysterophorus at Salem, Tamil Nadu :: Pix - Wikipedia/Thamizhpparithi Maari

Introduction: The menace of Congress grass (Parthenium hysterophorus L.) in the context of polluting environment, causing health hazard and disturbing biodiversity have been well aware of in various parts of the globe. However, for the North East India, the level of public awareness about this dreaded weed has not yet reached to the extent of our expectation.

For this purpose, the present writer and his team had reported –
(i) biological control of congress grass in NE India using Mexican beetles, (The Sangai Express, 12th October, 2015),
(ii) biological control of congress in NE India using sickle pod (The Sangai Express, 18th November, 2015),
(iii) Imphal city – call for public awareness (The Sangai Express, 7th June, 2016),
(iv) Capital cities of the North East India (Imphal vs Gangtok) (The Sangai Express, 4th October, 2016), and
(v) mass awareness on congress grass menace in NE (The Sangai Express, 13th June, 2017) for public awareness.

The writer and his collaborator, Dr. Sushil Kumar, Principal Scientist, Directorate of weed Research, Jabalpur (M.P) made frequent field visits to the North East India by road for possible biological based integrated congress grass management. Recently, both the investigators visited Agartala, the capital city of Tripura state by road from Guwahati (Assam) (19 to 22 September, 2017).

Prior to their Agartala visit, we visited/revisited various localities of Guwahati city and its adjoining areas (18th September, 2017) and releases Mexican beetles (Zygogramma bicolorata Pallister) for its acclimatization.

Field Surveys in NE India: Guwahati city and its adjoining areas (Assam) – On 18th September, 2017 we surveyed different localities of Guwahati city and its adjoining areas and also releases Mexican beetles to the localities mentioned below:-
Kamakhya Railway junction (1000 beetles),
Central PWD Office, GOI, Guwahati (1000 beetles),
road sides of Assam Engineering College, Guwahati (2000 beetles),
Govt. Ayurveda College, Guwahati (1000 beetles),
Gauhati University Campus, Jhallukbari (1000 beetles),
Horticultural Research Centre, Assam Agricultural University campus, Kahikuchi (1000 beetles),
Amingaon, North Guwahati (1000 beetles),
Narayana speciality hospital, Amingaon (1000 beetles),
IIT Gate, North Guwahati (5000 beetles).

Here we checked the presence of beetles that were released last year. We were lucky to recover beetles at the egg laying stage and some IV instar mature beetles. We visited road sides of the College of Veterinary Science, Assam Agricultural University, Khanapara and release beetles (20000 beetles). We also visited Silpukhari areas, judge field Cotton College, Handique College areas and releases beetles (4000 beetles).

Meghalaya, South Assam and Tripura – On 19th September morning (8 a.m.) we left Guwahati for Silchar (South Assam) by road. On the way, we stopped and survey the presence of Parthenium at Jorabat (Meghalaya), Nongpok (Rhi bhoi district, Meghalaya), Jowai – Silchar crossing (West Jantia district, Meghalaya). Due to recently constructed Guwahati – Silchar 4 lane National Highway which is operational upto Jowai (Meghalaya), we could not locate Parthenium growing area especially on the road side.

At Jowai – Silchar crossing (Guest House N Restaurant), we spotted profuse growth of common ragweed (Ambrosia artemisiifolia L.), a cousin of Parthenium hysterophorus L. on either side of the National Highway.

The biodiversity of the road side flora was completely suppressed by the common ragweed. It continuous upto 10 km approximately. After Jowai area, road expansion upto Silchar especially hilly areas are still going on, as such the road is really in bad shape. We had to wait even 1 hour for road clearing by the JCB. So, no Parthenium plant growing area could be located. We reached Silchar around 10.30. pm and lodged at Hotel Geetaljali for the night halt.

On 20th September, we got up by 5.00 am and got ready for Silchar town survey for Parthenium growing areas, we visited Club road area, Silchar railway Station area, Silchar Medical College area, G.C. College area, etc, for about 3 hrs. But we failed to trace out Parthenium plant. Earlier visit to Assam University Campus which is 20 km away from the Silchar town, the writer had located Parthenium growing areas in the University campus.

After return to the Geetanjali hotel, we had our breakfast and left Silchar (South Assam) for Agartala (Tripura) by 8.45 am. On the way to Agartala, in the suberb of Silchar town, we located Parthenium growing areas and releases Mexican beetles (500 beetles). The road from Silchar to Badapur – Karimjang (Assam) is realy bad. The taxi driver faced a lot of trouble to negotiate with the road.

The road from Tripura – Assam border is good though not wide. We reached Guest house, College of Fisheries, Central Agricultural University, Lembucherra (Agartala) around 6.30 pm and halted night in its Guest house.

On 21st September, 2017 we left (8 am) Guest house, College of Fisheries, Lembucherra after breakfast (8.00 am) for local field survey of Agartala town. Prof. Badal Datta, Department of Botany, Tripura University, Suryamaninagar shared us one of the Research Scholars to guide us to visit different locations of Parthenium growing areas.

The locations we visited include International Fair Ground, Hapania (beetles releases 500), in and around Tripura Medical Collegem Hapania, (beetles releases 500) near G.B, hospital (Tila), Akhuopura road (beetles releases 1000) Airport road, Radhanagar Bus stand (North) (beetles releases 1000), Jogendranagar (Bon Kumari Bazar) (beetles releases 2000), Agartala – Assam Road (NH – 44) near Badarghat bund (beetles releases 4500), etc.

Altogether 9500 beetles were released in and around Agartala town and 500 beetles were released to the way. In addition to this, we also broadcasted 5 kg of Cassia tora seeds in those places where Parthenium is growing. Around 3 pm, we left Agartala town (Tripura state) for Silchar (South Assam) and reached Silchar by 10.30 pm. We were lodged again at the Hotel Geetanjali, Silchar.

On 22nd September, 2017 after breakfast (8.00am) we left Silchar (South Assam) for Guwahati via Shillong. We reached Shillong (Meghalaya) by 4.00 pm and surveyed for Parthenium growing areas but not found. We left Shillong by 6.00 pm Guwahati (Assam) and reached Guwahati by 9.30 pm and lodged at Hotel Mayur for the night.

On 23rd September, 2017 morning 8.00 am we left Hotel Mayur for Lok Priya Gopinath International Airport, Guwahati. Then, the writer left Guwahati for Imphal. The other Investigator left Guwahati for Jabalpur (M.P). It was a challenging field trip with a lot of new experiences.

Mass Awareness on Congress grass (Parthenium hysterophorus L): As a part of all India Parthenium week celebration (16-22 August, 2017), a lecture by power point presentation was held at the North Point Higher Secondary School, Imphal on 22nd August, 2017 on the topic "Parthenium menace in NE India in the context of health (human and livestock), environment and biodiversity".

About 250 students attended the function. The lecture was followed by interaction between the teachers and students of the said school with the present writer. It as followed by release of about 1000 Mexican beetles by the students of the school along the NH-39 where Parthenium plants are growing profusely.

Discussion: From our field surveys, we have realised that congress grass (Parthenium hysterophorus L.) is a wide spread invasive plant in the NE India specially in the National Highways through the vehicular movements. The plant has been spreading vigorously. In some areas the biodiversity has been completely changed.

In addition to congress grass, common ragweed (Ambrosia artemesiifolia), a cousin of congress grass has been observed widespread along the Jowai (Meghalaya) – Silchar (South Assam) road. This is also another invasive plant which may caused health hazard in the region in near future.

Conclusion: For management of congress grass in NE India, Integrated biological based control by using Mexican beetles (Zygogramma bicolorata Pallister) and Sickle pod (Cassia tora) were only option for its management. During this trip we released 30,000 beetles in the Parthenium growing areas. However, the writer prefers to sickle pod (Cassia tora) because this plant is already available in our environment.

Therefore, broadcasting of sickle pod seeds in the young Parthenium growing areas will suppress the growth of congress grass in the areas under consideration.