Environmental bio pollution in Manipur due to massive Parthenium infestation and its management

Dr N Irabanta Singh *

Introduction

The growing concern over protection of the environment has rapidly developed on a worldwide scale during the past few decades in particular, resulting into the passing of a resolution during United Nations Conference on Human Environment held in 1972 at Stockholm (Sweden).

The awareness on the pollution of environment induced establishment and attention of several agencies like the United Nations Environmental Programme (UNEP), the Global Environmental Monitoring Systems( GEMS), the International Referral System (IRS), the United Nation Organization on “ Habitat”, the World Health Organization (WHO), the World Life Organization (WLO) and a host other bodies those which are dealing with the environmental problems on a global scale.

On 5th June 11, 2019, the World Environment Day was observed throughout India as done in other parts of the World. The observance of the World Environment Day every year with due solemnity it deserves, is a clear index and symbolic of the people’s anxiety to keep the environment free from the hazards of pollution. The environmental consciousness is often synchronized with the tree planting ceremony or Vanamahotsov.

It is learnt that under the initiative of Education Minister, Manipur, The World Environment Day, 2019 was celebrated by planting more than 50,000 tree saplings within one hour in 950 Schools and 80 Colleges of Manipur. The writer however had reminded about “Tree Plantation Vs Post Plantation Surveillance” (TSE June 21, 2016). Because, the Post Plantation surveillance is essential for proper check up of sapling that were planted.

Bioparticles in atmospheric pollution: Algae forms, fungal spores and pollen grains are the major organic constitutes of the atmosphere. The very nature of the environmental biopollution problem varies widely from area to area, depending upon the characteristics of meteorology, topography, source points, etc. To determine the potentiality of the incidence of airborne bioparticles, periodical data of quantity, quality, distributional pattern and period, dispersal mechanism, rate of production, etc are to be recorded.

Parthenium hysterophorus L. commonly known as Carrot weed or Congress grass in India, has spread throughout India after its noticeable occurrence in Pune in 1955. Now, it has achieved the status of “Worst Weed” owing to its allelopathic effects on agricultural crops and harmful effects on man and animals. Earlier, Parthenium used to be considered as a weed of fallow and wastelands but now its impact on agricultural and forestry crops has also been documented. Our studies revealed the presence of pollen grains of Parthenium in the atmosphere of Manipur valley throughout the year.

The highest monthly Parthenium pollen grains concentration was found in June followed by July and September in Horizontal profile whereas in the vertical profile, the highest monthly Parthenium pollen grain concentration was found in July followed by June and September. The influences of meteorological factors such as temperature, wind speed, rainfall and relative humidity on the variation patterns in the concentration of the atmospheric Parthenium pollen grains were studied.

It was observed that 250C to 280C temperature, 4-5 km/h wind speed, 60% to 70 % RH, bright sunny and rain free days were favourable for high P. hysterophorus L. pollen catch. These weather conditions might be conducive for the high discharge, dispersal and deposition of P.hysterophorus L.pollen grains. Too low or too high temperature, very high wind speed, high humidity and cloudy and rainy days hindered high Parthenium pollen grains catches.

Parthenium infestation in Manipur Valley: Three National Highways are passing through Manipur, which connect the State to other States of India and Indo- Myanmar border. NH-39 connects to Dimapur (Nagaland) in the North and Indo-Myanmar border in the South. NH-53 connects to Silchar (Assam) and NH-150 connects to Jessami (Nagaland) in the North and Mizoram in the South. Among the survey sites in Manipur, Parthenium was spotted highest in the State highway ( Mayai Lambi) followed by NH-39, NH-150 and NH-53.

In the survey sites of Mayai Lambi State Highway, 4 places were spotted, viz.,Keishamthong, Heirangoithong, Konjeng Leikai and Langthabal Makha Leikai where Parthenium was found growing luxuriantly as mono cultural stand upto the length of 100-200 m. Almost all the selected NHs and State highways of Manipur valley had a massive infestation of Parthenium weed except NH-53. In the roadsides in State Highway (Mayai Lambi), Parthenium was found to be heavily infested and spreading faster than the other sides, which may be attributed to spread of seeds by wind or vehicle.

It might have been spread by water runoff of the river Nambul which is flowing along the side of Mayai Lambi State highway. Lately, Parhenium has started infestation in the Imphal Municipal Corporation area viz., Singjamei- Kongba road, Kongba- JNIMS road upto Khurai, Kwairamband bazar to Sagolband –Tera Bazar, Kwairamband bazaar to Uripok Kangchup Road, etc. In term of density nd infestation level in the North East India as compared to other States of India, it is moderate in Assam and low in Manipur, Arunachal Pradesh, Meghalaya and Nagaland. For Mizoram, Parthenium is yet to be detected because in our survey sites, we find to notice this plant.

Thounam Macha (Cassia tora or sickle pod) to replace Parthenium infestation in Manipur valley

A core infestation of Parthenium weed is seen in the whole of Imphal and its suburbs having mean frequency of 51%. The growth of the weed was so dense that most of the quadrats taken include Parthenium weed. The predominance of Parthenium weed was recorded at 4(four) location under studied. The relative frequency weed is found good through statistical analysis showing the distribution of flora in an area.Parthenium weed, however, ranked at the second top emerging as the most prevalent weed at all the location as well as average importance value for all the 4 ( four) studied locations is 32.33 %.

About 300 kg of Cassia tora seeds were bought from local people and healthy seeds of C.tora were broadcasted al the rate of 1000/m2 before monsoon, on the pre-identified Parthenium infested sites. The impact of C.tora on growth and development of P. hysterophorus L. was monitored for 2 (two) years (2016 &2017) during monsoon as well as during post monsoon period. Field experiment results indicate that the growth Cassia tora severely inhibited the growth and development of P. hysterophorus L. plants.

The result revealed that there was an average height reduction by over 38% to 43% from 2016 to 2017.The population and dry matter production of P. hysterophorus due to suppression by C.tora was significantly reduced from 2016 to 2017. It was observed that Parthenium population was reduced by 28% to 30%. Similarly, C.tora had strongly inhibited the dry matter production in Parthenium also.

It was observed that there was percentage reduction of dry matter in Parthenium by over 57% to 62% from 2016 to 2017. It was also observed that seedlings of Cassia tora were found to be larger than Parthenium due to which C. tora grew faster and had taken over the Parthenium. Eventhough, Parhenium is known for its allelopathic nature on other weeds or plants, Cassia tora can suppress the growth of Parthenium to a great extent.

The reason may be due to their larger leaf size in early stage than Parthenium which overtakes Parthenium and keeps them under control. The plants in early phonological stages exhibit higher metabolic activities resulting in biosynthetic and accumulation of potential allelochemicals and release them into the soil as root exudates.

How to identify Parthenium and how to kill it?: The plant grows to a height of 1.5- 2 m, much branched, leaves covered with fine hairs, can produce; large number of seeds (upto 25000 seeds by a single plant); seeds are extremely light and armed with pappus; propagates through large number of tiny seeds and can regenerates from cut plants; density varies from 25-70 plants and flourishes throughout the year due to photo and thermo insensitivity.

Parthenium can be killed by uprooting completely and destroying when noticed; by releasing Mexican beetle (Zygogramma bicolorata) for the sustainable control; by spraying glyphosate(1.0 -1.5%) for total vegetation control or metribuzing (0.3 -0.5%) if grassed are to be saved and by utilizing Parthenium biomass for making compost and vermicompost.

Awareness creation: The awareness programme regarding the ill effect and management strategy of Parthenium have been conducted in different States of North East India including Manipur. Extension bulletin (English, Bengali script Manipuri and Meitei Mayek) have been distributed to Schools, Colleges, Universities including representative member of the Gram Panchayat. Articles related to the awareness of Parthenium have been published in local newspapers (English medium).

Some of them are :
(i) Biological control of congress grass in NE India using Mexican Beetles (The Sangai Express-12 Oct,2015);
(ii) Biological control of Congress grass in North East India using Sickle pod (The Sangai Express - 18 Nov,2015);
(iii) Imphal city: Call for public awareness (The Sangai Express - 18 Nov, 2016);
(iv) Can we eradicate Congress grass from NE India? (The Sangai Express - 4 July,2016);
(v) Mass awareness on Congress grass menance in the North East India (The Sangai Express -13 June,2017);
(vi)Biological based integrated Congress grass management in NE India (The Sangai Express - 2Nov, 2017);
(vii) Congress grass menance in North East India (The Sangai Express - 26 July, 2018) and
(viii) Bye Bye Congress grass, let us work with combined efforts for biological based integrated management of the weed (The Sangai Express -18 Dec,2018).

Future strategy:

(i) Mapping of Parthenium infested area;
(ii) Large scale demonstration with people’s participation in different districts of Manipur;
(iii) Publication and distribution of extension bulletins in vernacular languages;
(iv) Involvement of mass media for regular broadcasting/ publications of information on Parthenium management and their spread; (vi) Regular monitoring and eradication of Parthenium in newly infested areas;
(vii) Proper quarantine measures are to be taken to prevent the infestation of weed in new area;
(ix) Lectures/demonstration Programme on Parthenium control is to be ensure through Municipal Corporations, Gram Panchayats, development authority ;
(x) Other transport Organizations etc.

Conclusion: People’s participation is the only means to eradicate Parthenium from the soil of Manipur.