Many non-native weeds have become threat to cropland and non-cropland ecosystems in India. The potential threat from such weeds is evident in the form of yield losses, damage to plant biodiversity and effects on health and environment. In India both cropland and non-cropland ecosystems have suffered severe losses due to many invasive weeds such as Phalaris minor, Parthenium hysterophorus, Lantana camara, Chromolaena odorata, Mikania micrantha, Salvinia molesa, Eichhornia crassipes etc., In the past efforts have been made to address the problem but the outcomes were short of expectations. In this scenario it is imperative to continue efforts on priority basis to contain the invasive weeds as the risk is very high even at low levels of their infestation. To ascertain the weeds which directly or indirectly have impact on economy and ecosystem in India, a platform for thorough deliberations is needed to pave way for future plan of action. In this context a webinar on “Weeds of National Importance (WONI)” was organized on 25th February 2021 with the joint efforts of ICAR-DWR and ISWS.

This webinar was chaired by the Dr. J.S. Mishra, Director, ICAR-DWR, Jabalpur and convened by Dr. Anil Kumar, Principal Scientist and PI (AICRP), SKUAT, Srinagar. Dr. Sushil Kumar, Principal Scientist (DWR, Jabalpur) & President, ISWS, has delivered the talk on this important topic.

The speaker has presented the overall scenario of invasive weeds and their impact on crop production and ecosystem. He discussed in detail the attempts made so far by the Indian weed science fraternity to deal with those exotic weeds which have major share of impact on crop production, health and environment. He sincerely expressed his views that the achievements so far, with respect to the containment of designated weeds are not significant and he emphasized the need to take forward the efforts.

Post presentation, the topic was discussed in depth by the personnel of eminence in weed science. Dr. N.T. Yaduraju, Dr. Samunder Singh, Dr. B.S. Chouhan, Dr. Majumdar, Dr. T.V. Ramachandra Prasad, Dr. C.T. Abraham, Dr. Moolchand, Dr. Dekha, Dr. I.C. Barua, Dr. N.N. Angiras, Dr. Geetha Kulshreshta and many experts have expressed their views.

The following points with consensus have emerged from the discussion

1. Development of the criteria for designating a weed as one of national importance
2. Make use database already available
3. Profiling the database with GIS mapping.
4. Executing a separate project for’ WONI’ in the similar lines of AICRPWC.
5. Stakeholders need to be brought into.
6. Collaborative efforts involving DPPQS, NIPHM, National Biodiversity Authority etc.
7. What next after ascertaining weeds of national importance?
8. Take into consideration the policy aspects of the country.

A total of 205 members have actively participated in the webinar. Dr. V.S.G.R. Naidu, Principal Scientist & Head (KVK), ICAR-CTRI, Rajahmundry (A.P), has conducted this Webinar and proposed vote of thanks.

Topic: Alien invasive weeds in India: Threat to agriculture, biodiversity and environment
Lead Speaker: Dr. RM Kathiresan, Professor of Agronomy, Annamalai University, Tamil Nadu
Organizers: Indian Society of Weed Science & ICAR-DWR, Jabalpur
Date: 30-04-2021
Chairman: Dr. Sushil Kumar, Pr. Scientist & President, ISWS
Convener: Dr. TK Das, Professor & Pr. Scientist, ICAR-IARI, New Delhi & Vice-President, ISWS
Organizing Secretary: Dr. JS Mishra, Director, ICAR-DWR & Secretary, ISWS

Brief Report
Invasive Alien Weeds (IAW) have become major threat to biodiversity and environment, besides reducing crop yields, and having adverse effects on human and animal health. Dr. RM Kathiresan, Professor of Agronomy, Annamalai University, Tamil Nadu, highlighted the invasive potential of IAW with respect to greater genetic variability, climatic adaptability, and biotic factors such as allelopathic potential and absence of natural enemies. He cited the examples of Prosopis juliflora, Trianthema portulacastrum, Echinochloa colona, Leptochloa chinensis and Marsilea quadrifolia, and described how these weed species are tolerating climatic fluctuations and becoming invasive weed species. He emphasized to focus more on studying the biology and ecology of IAWs. Since, herbicides are lethal to fish, other means of management of invasive aquatic weeds like water hyacinth using allelochemicals from Coleus amboinicus is suggested. There are some ‘sleeper weeds’ which are more dangerous under changing climate scenario. More emphasis need to be given on developing protocols for Weed Risk Analysis of alien invasive weeds of the country. In addition to control, mass awareness programmes related to invasiveness and ill effects of these weeds need to be initiated to make the public and policy makers aware of the ill effects of these weeds. More than 140 weed scientists attended this webinar, and there was a very fruitful discussion. From the interaction/discussion between the speaker and learned guests/participants, the following points emerged out:

• There is a need to assess the area coverage under different IAWs in India under different Agro-ecological regions and their economic and environmental impacts.

• There is a need to develop good publications on major IAWs. Few important IAWs need to be targeted with time. Some good projects on IAWs need to be submitted to ICAR/DST/DBT for financial assistance.
• More emphasis needs to be given on biological control of these weeds in collaboration with NBAII, Beangaluru.

Topic: Aquatic weeds: Problems and their management for improving water productivity
Lead Speaker: Dr. Sushil Kumar, President, Indian Society of Weed Science (ISWS), and Principal Scientist, ICAR-Directorate of Weed Research (DWR), Jabalpur
Organizers: ISWS & ICAR-DWR, Jabalpur
Date: 29-05-2021 (11.30 AM)
Chairman: Dr. S. Bhaskar, ADG (Agronomy, Agro-forestry & Climate Change), ICAR, New Delhi
Convener: Dr. CR Chinnamuthu, Vice-President, ISWS, and Professor & Head, Deptt. of Agronomy, TNAU, Coimbatore
Organizing Secretary: Dr. JS Mishra, Secretary, ISWS & Director, ICAR-DWR, Jabalpur

Brief Report
Water is one of most important natural resource and in fact basis of all life forms on this planet. Therefore, appropriate management of water from source to its utilization is necessary to sustain the normal function of life. India is a home to 18% of the global population but has only 4% of the global water resources. Its per capita water availability is around 1,100 cubic meter (m3), well below the internationally recognized threshold of water stress of 1,700 m3 per person, and dangerously close to the threshold for water scarcity of 1,000 m3 per person. India has 1.9 m ha under water in reservoirs and 1.2 m ha under irrigation canals. The area under village ponds and tanks is nearly 2.2 m ha. About 1.0 million ha of inland water-area in this country is threatened by the invasion of noxious aquatic weeds. Aquatic weeds are posing serious threats to water availability, fishing and navigation, other aquatic flora and fauna, aesthetic value of water bodies, productivity of irrigation and hydroelectric projects, ecosystem services, human health, etc. Out of about 160 aquatic weeds, Eichhornia crassipes, Ipomoea aquatica, Typha angustata, Ceratophyllum demersum, Salvinia molesta, Nelumbo nucifera, Alternanthera philoxeroides, Hydrilla verticillata, Vallisneria spiralis, Chara spp., Nitelia spp., Potamogeton spp. are of primary concern in India.
To commensurate with the Govt. of India’s mission “Bharat ka Amrut Mahotsav” commemorating 75 years of India’s Independence, it was thought appropriate to organize this Webinar under the NRM theme “Improving water productivity”. The lead speaker Dr. Sushil Kumar, President, Indian Society of Weed Science (ISWS), and Principal Scientist, ICAR-Directorate of Weed Research (DWR), Jabalpur, very comprehensively delivered the talk covering different aspects that included types of aquatic weeds viz., floating, submersed, and semi aquatic, etc., their biology, losses, management strategies (physical, mechanical, chemical and biological), and various ways of utilization, especially for water hyacinth. Because of the multiple use of water and herbicide residue problems, label claims for herbicide use have not been given (except for 2, 4-D) for management of aquatic weeds. He presented in detail that how the integrated approach using Neochetina beetle and mechanical removal has helped in managing water hyacinth in Moti lake of Motihari district of Bihar and a big pond in Haliyal village of Dharwad district of Karnataka. The removed biomass of water hyacinth is a rich source of nutrients, and can be easily converted in to rich organic manure through vermicomposting.
Dr. S. Bhasker, the Chairman of the Webinar highlighted the issue of aquatic weeds in lakes and aquatic crops like Makhana, water chestnut and others in wetland ecology of eastern India, and its effect on fishing and navigation. He also stressed upon estimation of evapotranspiration losses caused by different aquatic weeds, estimation of carbon sink, ecosystem services, biodiversity contribution, ecosystem services, etc of different aquatic weeds. There may be a trade-off between water loss and biodiversity gain, he added. Mapping of lakes and water bodies infested with different aquatic weeds need to be carried out.
More than 500 participant including scientists, students, representatives from herbicide industry and other stakeholders, attended this webinar through virtual mode including Zoom link and Facebook. After the deliberation, there was a very fruitful discussion. Dr. CT Abraham from Kerala raised the issue of using herbicides for aquatic weed management because water has multiple uses. As these weeds are used for phytoremediation of polluted water, local municipal authority should see that the heavy metal containing water should not be allowed to flow in ponds/lakes, if we remove the aquatic weeds from the ponds. Dr. AS Rao from Andhra Pradesh raised the issue of management of aquatic weed in aquaculture, which was suitable replied by the speaker. Dr. TK Das from, IARI, New Delhi wanted to know the conversion ratio of water hyacinth for vermicomposting. Dr. RM Kathiresan clarified that the conversion ratio of water hyacinth to vermicompost is 35:1. He emphasized more on inundative approach using bio-herbicides for management of aquatic weeds. Dr. TV Ramchandra Prasad from Bengaluru suggested to include grass carp also as a biocontrol agent for aquatic weed management. Dr. JC Majumdar from Herbicide Industry wanted to know if there is any National programme on management of aquatic weed in India, which was clarified as there are state sponsored management programmes, but not at the national level. Dr. IC Barua from Assam pointed out that Salvinia is not a problem in north-east, rather Ludwigia peruviana and Alternenthera philoxuroided are upcoming threats to rice cultivation in many north-eastern rice growing areas. In addition to water hyacinth, there is a need to focus other aquatic weeds also, he added. Dr. Chinnamuthu, from TamilNadu wanted to know if there are some growth retardants to check the growth of aquatic weeds. It was also suggested that Drone Technology can be evaluated for spraying herbicides in lakes and bigger ponds infested with aquatic weeds. Dr. JS Mishra, Director DWR and organizing Secretary suggested that a comprehensive study need to be initiated for management of aquatic weeds including water quality, effect on aquatic flora and fauna, ecosystem services, water quality, trade-off, etc. There is a need to monitor weed shift in aquatic system and effect of climate change on weed flora and bioagents. Need-based mechanical tools need to be developed to remove aquatic weeds, he added. In his concluding remarks, Dr. S. Bhaskar, Chairman suggested that an integrated approach involving local community is needed to manage the aquatic weeds in water bodies. Use of herbicide in aquatic environment is risky. It will further add to water pollution. Mechanical removal of the weed involving Government schemes like MNREGA and local communities may be the better option. There is a need to initiate the research to prevent weed seed germination using pre-emergence herbicides in dry water bodies. This can be done under AICRP-WM programme, he added. He also pointed out the as the bioagents are season bound, their multiplication throughout the year may a major problem. Generation of data bank on aquatic weeds and mapping is required to sensitize the policy makers.
Dr. CR Chinnamuthu, Vice-President, ISWS and Convenor of the programme, proposed the vote of thanks.

(JS Mishra)
Secretary, ISWS

Topic: Role of weed biology in improving weed management strategies
Lead Speaker: Dr. Bhagirath Singh Chauhan, Professor (Weed Science), School of Agriculture and Food Sciences, The University of Queensland | QAAFI, Queensland, Australia
Organizers: ISWS & ICAR-DWR, Jabalpur
Date: 22-06-2021 (11.00 AM)
Chairman: Dr. R.K. Malik, Former President,Indian Society of Weed Science
Convener: Dr. Sushil Kumar, President, Indian Society of Weed Science
Organizing Secretary: Dr. JS Mishra, Secretary, ISWS & Director, ICAR-DWR, Jabalpur

Brief Report
To commensurate with the Govt. of India’s mission “Bharat ka Amrut Mahotsav” commemorating 75 years of India’s Independence, an International Webinar on “Role of weed biology in improving weed management strategies” was organized on 22-06-2021. The lead speaker Dr. B.S. Chauhan, Professor (Weed Science), the University of Queensland, Australia, very comprehensively delivered the talk covering different aspects of weed biology including weed seed dormancy and germination, phenology, competitive ability, reproductive biology, seed bank dynamics, seed persistence etc., and effect of environmental factors such as light, temperature, climate change effect in respect to elevated carbon dioxide, temperature and water, drought; and management practices like tillage on weed seed germination and reproductive capacity.

Weeds are one of the major biotic stresses in agriculture, causing >11 billion US$ economic loss annually to Indian farmers in 10 major crops only. In addition, problem of herbicide resistant in weeds is also increasing, and no new herbicide molecule with different mode of action has been developed since last three decades. Therefore, proper knowledge and understanding of weed biology and ecology is required to develop sustainable weed management practices. It is very much required to understand that how some of the weed biology parameters can be used for developing IWM practices. Dr. Chauhan nicely articulated the need of basic research on weed biology for the future weed management.

Dr. Chauhan talked about the effect of light and seed burial depth on germination and emergence of different weed seeds. Some of the weeds like Sonchus spp. and Malva spp. do not require light for germination. Night cultivation could also results in significant reduction in weed density of Chenopodium and Amaranthus. Dr Chauhan also narrated the examples of the farmers in Australia that to prevent the germination of weeds they do cultivation during night. He also cited the examples that how no-tillage (NT) affects weed seed germination. In NT, most of the weed seeds accumulate on surface soil, and one deep tillage after 7-8 years is required to burry these weed seeds deep in the soil. Seeds of Echinochloa spp. can germinate even after the crop canopy closure. Seeds of Leptochloa chinensis does not germinate if placed >0.5 cm depths. More than 90% weed seedlings emerge from top 2.0 cm soil.

Temperature also plays an important role in weed seed germination. Some population showed higher germination at lower temperature. Weeds may change seasonality and become major weed in other seasons as well. He quoted the examples of Sonchus, Rye grass and Chenopodium album. To break the physical dormancy due to hard seed coat, scarification is required. Tillage systems affects the seed burial depth and also influences the seed dormancy. The knowledge of weed emergence pattern will help in developing the decision support system (DSS) on weed management, he added. Water stress also influences the plant growth and herbicide efficacy by influencing opening of stomata. Efficacy of glyphosate is reduced at high temperature. Similarly, the efficacy of herbicide is also reduced at elevated CO2 level due to larger plant size.

Chairman Dr. Malik while summarizing the whole discussion emphasized that the knowledge of weed biology is required to develop sustainable IWM practice. A network programme on studying weed biology involving AICRP-WM centres is required, he added. More than 409 participant including scientists and students from various ICAR Institutes and Universities attended this webinar through virtual mode besides 103 on Facebook and 7 on UTube. After the deliberation, there was a very fruitful discussion. Many weed scientist shared their views. A lot of questions were posted in chat box by scientist and students. Those questions which were not taken during the discussion due the paucity of time, have been sent to Dr. Chauhan with the request to reply individually.

Sushil Kumar, President, ISWS and Convener of the programme, proposed the vote of thanks.

(JS Mishra)
Secretary, ISWS

Topic: Restrictions in use of Glyphosate: Implications in weed management
Organizers: ISWS & ICAR-DWR, Jabalpur
Date: 20-07-2021 (11.00 AM)
Chairman:Dr. Sushil Kumar, Pr. Scientist, ICAR-DWR, Jabalpur& President, ISWS
Convener: Dr. CR Chinnamuthu, Prof. & Head (agronomy), TNAU, Coimbatore &Vice-President, ISWS
Organizing Secretary: Dr. JS Mishra, Secretary, ISWS & Director, ICAR-DWR, Jabalpur

Brief Report
To commensurate with the Govt. of India’s mission “Bharat kaAmrutMahotsav” commemorating 75 years of India’s independence, a stakeholders dialogue was convened in a virtual mode by the Indian Society of Weed Science (ISWS) and ICAR-Directorate of Weed Research (DWR), Jabalpur on 20-07-2021, to have more scientific discussions and clarifications on the proposed “Restrictions on use of Glyphosate through PCOs” by the Government of India (Draft Glyphosate order 2020). More than 55 stakeholders including scientists, Govt. officials, industry personals, and progressive farmers participated in this dialogue. The lead panellists included were: Dr. NT Yaduraju, former Director, ICAR-DWR; Dr.Ajit Kumar (Vice President, UPL), Dr. PJ Suresh (lead-Regulatory affairs, Bayer Crop Sciences), Dr. AK Reddy, Dy. Director (WS), CIB&RC, Dr.Shobha Sondhia, Pr. Scientist, ICAR-DWR, Dr. MS Bhullar, PI, AICRP-WM, PAU, Dr. P. Prameela, PI, AICRP-WM, KAU, Dr. T Ramaprakash, PI, AICRP-WM, PJTSAU; and two progressive farmers namely Mr. Satish Dubey and Mr. Nalin Sharma from Jabalpur. In addition, Dr. RP Dubey, Pr. Scientist & I/C AICRP-WM, DWR, Dr. P. Murali and Dr. CR Chinnamuthu from TNAU Coimbatore, Dr Neelam Sharma from HPKVV Palampur also took part in the discussion.

In his opening remark, Dr. JS Mishra, Director ICAR-DWR, Jabalpur, and Secretary, ISWS made a brief presentation on the Glyphosate, its developmental history, usage, development of roundup ready GM crops like soybean, cotton, maize, etc., significant increase it its consumption, its positive and negative impacts on agricultural production and environment, restrictions in some States on its use, and Government of India’s view on restricted use in pesticides, label-claims and other requirements for the safe use of pesticides, and set a stage for further discussion. Dr. NT Yaduraju said that the Glyphosate is very cheap and effective herbicide with the least residual problems. More studies need to be done on the risks involved with glyphosate use. Because of the illegal cultivation of Bt cotton in some states, it is being used indiscriminately. Proposal on application of glyphosate through PCOs need to be relooked in view of its availability in rural areas. Dr Ajit Kumar told that the Industry has already submitted the clarifications as required by the Govt. of India. Restrictions on use of this herbicide should be based on scientific evidences. PCOs are not going to solve the problem. Dr. PJ Suresh opined that glyphosate is highly safe, effective and economical herbicide. Its risk assessment has widely been done. He further said that, if required, more scientific assessment can be made on glyphosate. He emphasised on upgradation and strengthening of the PCOs. Dr. AK Reddy put the views of CIB & RC, as to how the question of its restricted use came in discussion, and the progress made there after by the Government. Dr.Shobha Sondhia discussed more on the toxicological profile of the herbicide, and suggested to have proper documentation of the scientific evidences related to its use, safety and environmental impacts. As the safety of the farmers is the first, she advocated the use of glyphosate through trained persons like PCOs. Dr. Prameela, discussed about the residual effect of glyphosate on soil microbes, earthworms, and fishes. Its detrimental effect was noticed on fishes, she added. Dr. MS Bhullar suggested for its use in only those crops and areas where it has the label-claim. Dr.Ramprakash said that farmers in Telangana are ready to replace glyphosate provided a cheap substitute is available. Progressive farmers also suggested that glyphosate is economical and effective herbicide, but it should be used by trained persons to avoid any hazards.

Chairman Dr. Sushil Kumar while summarizing the whole discussion emphasized that no doubt, glyphosate is cheap and effective herbicide, and is used in many crops and areas other than those having label-claims, therefore, the industry should generate more data and submit to CIB & RC for expansion of its label-claims, so that the farmers should not be deprive of the benefits of this herbicide. There is a need to train the stakeholders regarding safe use of this herbicide. The PCOs need to be strengthened in terms of the numbers and knowledge, so that they can reach to farming community as and when required with minimum costs involved. More scientific studies on environmental impact of glyphosate including human and animal health, need to be carried out.

Dr. CR Chinnamuthu, Vice-President, ISWS and Convener of the programme, proposed the vote of thanks.

(JS Mishra)
Secretary, ISWS

Topic: The Parthenium weed problem and its weed management at Global the level
Lead Speaker: Dr. Steve W. Adkins, School of Agriculture and Food Sciences, University of Queensland, Brisbane, Australia
Organizers: ISWS & ICAR-DWR, Jabalpur
Date: 22-06-2021 (11.00 AM)
Chairman:Dr. A.K. Pandey, Vice Chancellor, Vikram University, Ujjain
Convener:Sushil Kumar, Pr. Scientist, ICAR-DWR, Jabalpur & President, ISWS
Organizing Secretary: Dr. JS Mishra, Secretary, ISWS & Director, ICAR-DWR, Jabalpur

Brief Report
To commensurate with the Govt. of India’s mission “Bharat ka Amrut Mahotsav” commemorating 75 years of India’s Independence, the Directorate of Weed Research, Jabalpur in collaboration with Indian Society of Weed Science (ISWS), Jabalpur organized an International Webinar on ‘The Parthenium weed problem and its weed management at Global the level’ on 16-08-2021. Professor Steve Adkins from the University of Queensland, Australia delivered a lead talk on the subject, covering possible reasons for becoming this weed so invasive, such as absence of natural enemies, genetic diversity and tolerance to biotic stresses, etc.; its biology and global distribution, losses to productivity of crops and biodiversity, invasion of grasslands and other ecosystems, human and animal health problems; and possible ways to manage this weed. Under changing climate scenario i.e. elevated CO2 conditions, the Parthenium being a C3/C4 photosynthetic pathway plant, grows vigorously and produced more number of seeds as compared to normal CO2 level, and therefore some weed management tools may become less effective. He gave major emphasis on biocontrol of Parthenium using Mexican beetle and other insects. However, he further explained that although biocontrol is very effective, it is not possible to eliminate Parthenium using only one strategy. Therefore, an integrated approach using weed suppressing plants and biocontrol strategy has been found quite effective in reducing the Parthenium weed seed bank in soil and further growth and development.

At the outset, Dr. S.K. Chaudhari, DDG (NRM) and Chief Guest of the programme, stated that the infestation of alien invasive weed Parthenium in India has increased with alarming rate in the recent past due to its tolerance to biotic and abiotic stresses, allelopathic potential, lack of seed dormancy, etc. It is a poisonous, pernicious, problematic, allergic and aggressive weed posing a serious threat to human beings and livestock. Management of this weed requires collective and continuous efforts through awareness and adoption of integrated approaches. He appeal to all the Vice Chancellors of SAUs, Directors of ICAR institutes and In-charges of KVKs to participate in this activity and ensure 'Parthenium-free campus'. Dr. S. Bhasker, ADG (A,AF & CC), and the Guest of Honour in the Webinar said that Parthenium is a serious threat to biodiversity. Under ‘Swachha Bharat Abhiyan’ there is a need to eliminate this weed from the society. Creating awareness about its ill effects is very important aspect, he added. Dr. A.K. Pandey, Vice Chancellor, Vikram University, Ujjain, and the Chairman of the programme appreciated the efforts of the Directorate for making the awareness programme. The Parthenium may cause more problems to human health due to reduced immunity under the present scenario of COVID 19, and urged the people to eliminate this weed from the society. He also emphasized to utilize this weed for vermicomposting before flowering.

In this webinar 478 participants from India, Pakistan and Bangladesh including scientists, students, and other stakeholders, were present in virtual mode. After the deliberation, there was a very fruitful discussion. Dr. Sushilkumar, President, ISWS and Convener of the programme, proposed the vote of thanks.

(JS Mishra)
Secretary, ISWS