IOBC Water Hyacinth Meeting

The second Working Group Meeting for the Biological and Integrated Control of Water Hyacinth held every 2 years under the auspices of the International Organization for Biological and Integrated Control of Noxious Animals and Plants (IOBC) took place in Beijing, China on 9-12 October 2000. This meeting brought together 31 delegates from 11 countries with the common purpose of identifying suitable biological and integrated control solutions for water hyacinth.

The meeting took the form of a series of oral presentations, which included three keynote presentations covering the biological control of water hyacinth using insects, the biological control of water hyacinth using pathogens both as classical biological control agents and as mycoherbicides, and an overview of the current status of research on the weed in China. In addition, there was a series of reviews from different countries around the world, several papers dealt with the need for additional biological control agents, both insects and pathogens, and there were several papers dealing with aspects of the integrated control of the weed. These papers will be published by ACIAR, in a proceedings, which is expected to be available in the first half of 2001.

One of the roles of this working group is to identify further research needs on water hyacinth. From the presentations and discussions the following ideas emerged for further investigation.

• Investigate the impact of cold climates on the success of biological control.
• Use plant competition studies between water hyacinth and other aquatic plants as an indication of how effective particular agents are.
• Investigate the compatibility of the different control options that could be used in integrated management.
• Select suitable locations and undertake integrated management of water hyacinth where biological control is the base technique.
• Identify and conduct surveys in areas where detailed surveys for additional natural enemies (both insects and pathogens) have not been conducted in the region of origin of water hyacinth.
• Research the interaction between insect natural enemies and pathogen natural enemies.
• Make a thorough investigation into the development of mycoherbicide for water hyacinth.

The workshop closed with a general meeting of the working group (the participants). During the meeting the following mission statement was developed for the working group:

"The mission of the IOBC Working Group for the Biological and Integrated Control of Water Hyacinth is to promote better management of water hyacinth through:

• facilitation of interactions,
• dissemination of information, and
• identification of research needs.

This will be achieved by:

• holding a meeting every 2-3 years,
• publishing the meeting proceedings, a water hyacinth newsletter and maintaining website,
• supporting activities that contribute to better management of water hyacinth."

The next meeting will be held in Uganda on the shores of Lake Victoria in early August 2002.

By: Martin Hill, PPRI, South Africa

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Fifth Chromolaena Workshop

The Fifth International Workshop on Biological Control and Management of Chromolaena odorata was held at the Umhlanga Protea Hotel near Durban, South Africa, on 23-25 October 2000, with a post-workshop fieldtrip to northern KwaZulu-Natal province from 26-28 October. It was organized by the Plant Protection Research Institute of the Agricultural Research Council of South Africa (ARC-PPRI) in association with the International Organization for Biological Control of Noxious Animals and Plants (IOBC), the provincial conservation service (KZN Wildlife) and Dr R.N. Muniappan of the University of Guam. This is the second time the workshop has been held in Africa (the first being the Third Workshop, held in Abidjan in 1993).

It was attended by 20 international delegates from 12 countries (India, the Philippines, Indonesia, Papua New Guinea, Guam (USA), Australia, Malaysia, Ghana, Congo-Brazzaville, Cameroon, Benin, Swaziland) and 30 South African delegates. These delegates included agriculturalists, water conservationists, biologists and nature conservationists. Major sponsors of delegates included the Australian Centre for International Agricultural Research (ACIAR) (for Southeast Asia) and the Technical Centre for Agricultural and Rural Co-operation (CTA) based in the Netherlands (for West and Central Africa).

The Workshop was opened by the Minister of Agriculture and Environmental Affairs for KwaZulu-Natal Province, Mr Narend Singh. The keynote address was delivered by the Chief Executive of the World Wide Fund for Nature (South Africa), Dr Ian Macdonald, and was entitled "Chromolaena at the cutting edge, or, Why the battle to control Chromolaena is a flagship battle for the new millennium". Dr Macdonald outlined his belief that, since chromolaena has all the characteristics of one of the world's worst invasive plants, if it can be beaten, any invasive can be beaten. As an invasive of tropical, largely developing countries, the successful struggle against chromolaena is a good indicator that we can get to grips with many of the underlying problems affecting conservation in the tropics, which is the repository for much of the world's biodiversity. Dr Macdonald's optimism for such success came from the fact that the chromolaena workshops are being held on a regular basis and that they are bringing together on-the-ground workers from the developing world; by the progress being made on biocontrol, a sustainable rather than symptomatic form of control; and by the global groundswell of awareness and action on invasive species.

Thirty-three oral and two poster presentations were made. Presentations were grouped into seven sessions with the following general topics:

• country and regional reports (13 papers),
• taxonomy, ecology and impacts of chromolaena (5 papers),
• impacts and management of chromolaena (4 papers),
• biological control of chromolaena (10 papers).

A mid-workshop tour on 24 October took delegates to the ARC-PPRI laboratories at Cedara to view the insects in quarantine presently being cultured and tested as biocontrol candidates on chromolaena and the South American invasive Solanum mauritianum (bugweed).

The workshop ended with an afternoon of:

1. Summarizing the workshop sessions.
2. Drawing up a list of biocontrol agents established in, available from and wanted by the various countries, and funding possibilities for regional biocontrol programmes.
3. The proposal and discussion of recommendations emanating from the workshop.

This information has been published in the Chromolaena odorata Newsletter No. 14.

The post-workshop fieldtrip afforded delegates the opportunity to see chromolaena in the field and its effect on renowned conservation areas such as the St Lucia estuary (a World Heritage Site) and the Hluhluwe-Umfolozi Reserve, at the historical centre of the effort to conserve both black and white rhinoceros. Control efforts on chromolaena and other invasive plants, undertaken by KZN Wildlife and the Department of Water Affair's Working-for-Water Programme, were also outlined on the trip.

Two of the highlights of the workshop were:

1. The progress that has been made since the Fourth Workshop (India, 1996) on chromolaena biocontrol research and implementation. This is largely due to the proactive role taken by ACIAR in Southeast Asia, and the South African and Ghanaian programmes. The tephritid stem-galling fly, Procecidochares connexa, is currently being distributed widely in Southeast Asia, where it is establishing readily and causing significant damage. The defoliating arctiid moth, Pareuchaetes pseudoinsulata, which has had an inconsistent history in terms of its success as a biocontrol agent around the world, is spreading and causing significant damage in both Ghana and Sumatra (Indonesia). The nymphalid Actinote sp., whose larvae defoliate chromolaena, was rejected as an agent for South Africa because it fed on indigenous Mikania species, but has been released in Sumatra, as Mikania is invasive there. Its establishment has yet to be confirmed. A number of promising new candidate agents are being tested in South Africa. These include the leaf-mining agromyzid fly, Calycomyza eupatorivora, and the stem-boring weevil, Lixus aemulus, both of which have been tested for host specificity to near-completion, with favourable results. The stem tip-galling weevil Conotrachelus reticulatus and the root-boring flea-beetle Longitarsus horni are also undergoing testing in South Africa. The ACIAR programme has also resulted in the establishment of centres of expertise in most Southeast Asian countries, for the testing and distribution of agents on chromolaena.

2. The progress made on unblocking the biocontrol programme on chromolaena in West and Central Africa. Due to perceived conflicts of interest over the role of chromolaena in agriculture here, outside of Ghana little progress has been made over the past decade on biocontrol of chromolaena. Discussion between parties representing these conflicting interests at the Fifth Workshop resulted in a commitment to host a meeting within the next year bringing together all stakeholders in West and Central Africa.

In addition, several delegates who had not visited South Africa previously and thus not seen the southern African form of chromolaena were struck by its different growth habit, morphology and ecology. That this form of chromolaena has a different biology (e.g. susceptibility to fire) to that invading other areas of the world was also evident from research presented at the workshop.

Papers for the Proceedings are currently being collated for refereeing. The Proceedings will be published during the course of 2001.

By: Costas Zachariades, PPRI, South Africa

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IOBC Fungal and Bacterial Plant Pathogens Workshops

A workshop of the IOBC/WPRS Working Group 'Biological Control of Fungal and Bacterial Plant Pathogens', held in Taormina, Sicily in September 2000, focused on the biocontrol of foliar pathogens. Organized and chaired by Yigal Elad (Bet Dagan, Israel) in cooperation with EFPP (the European Foundation of Plant Pathology), it was attended by some 200 people, and was devoted to the interaction of biocontrol agents with foliar plant pathogens, and to biological control and its mechanisms. Presentations included: an introduction to the subject and field use of a biocontrol preparation; induced resistance to control leaf pathogens by microbial inoculants that are applied to the root system; strategies and application of biological control for a disease of stone fruits; and how it is possible to cope with variability and inconsistency of biocontrol.

The sixth workshop of the Working Group, held on 30 November-3 December 2000, focused on 'Biocontrol agents, modes of action and their interaction with other means of control'. The meeting, organized by Enrique Monte (Salamanca, Spain) and Yigal Elad, with local and international cooperation, was attended by 108 people from 33 countries. Presentations and discussions focused on the use of biocontrol agents against soilborne and foliar pathogens of all kind of plants either in the open field or in greenhouses and at post harvest stages, in the roots, stems, leaves, flowers, fruits and wood. It dealt with the use and implementation of biocontrol, various modes of action, the nature and use of genes that originate from biocontrol agents, involvement of mycorrhizae and improvements of biocontrol activity. Modes of action that were dealt with can be categorized as competition including space and nutrient exclusion, parasitism including phages that are hosted by bacteria, antibiosis, different modes of induced resistance, restraining the pathogenicity enzymes of the pathogen and its antigens, and arresting the production of multiplication propagules of the pathogens. It was noted that in many systems multiple modes of action are involved. Several commercial biocontrol agents were presented. The improvement of efficacy, integration of biocontrol agents among themselves and with other means of disease control were discussed with respect to the improved implementation of biocontrol and the reduction of variability in the performance of biocontrol agents.

By: Yigal Elad, Bet Dagan, Israel

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