SPC: A regional research initiative is looking at innovative approaches to induce activators in plants to enhance their defences to fight off pests and diseases. The research is focusing on a mechanism by which an activator trips the plants’ own defensive shield. The research work being implemented by the Secretariat of the Pacific Community (SPC) with donor partners is part of an integrated effort to find sustainable pest management regimes for high value crops such as vegetables.
Also under investigation is assessing biochemical activators where a plant under attack by pests and diseases sends out a sensory distress call for a cavalry of natural enemies to fight off the invaders.
At the fourth meeting of the Project Advisory Group (PAG) for the SPC-implemented Integrated Crop Management (ICM) regional project held in Samoa on 17–21 February, delegates reviewed these pest management approaches and others with the aim of identifying alternative strategies for the sustainable management of pests and diseases.
The ICM project is a collaborative effort of regional and international stakeholders implemented by the SPC Land Resources Division with donor partners the Australian Centre for International Agricultural Research (ACIAR), the University of Queensland, Terra Circle with the Commonwealth Agricultural Bureau International, and the World Vegetable Center. To further strengthen the research, a UN Food and Agriculture Organization (FAO) Technical Cooperation Programme (TCP) is funding parallel activities to promote techniques to reduce hazardous pesticide use and strengthen integrated pest management in the Pacific.
At the official opening of the PAG Meeting at Nu’u Crops Station, Minister for Agriculture and Fisheries, Le Mamea Ropati extended a warm welcome to meeting delegates on behalf of the Samoa government, thanking organisers for bringing the meeting to Apia. He told participants that pesticide use in agriculture is common in farming communities and has become a part of farming life. ‘Insecticides are helpful to control insect pests to improve crop yields,’ he said, noting that yield is often the main focus of farmers, who may have little concern for residues in the crops.
‘However, we know that pesticides are poison, formulated to kill insect pests and stop spread of disease. But overuse can cause bad effects that could be harmful to human health and environment. The non-target organisms which are useful to control pests such as pollinators and natural enemies like spiders and beetles are also affected.’
The minister acknowledged technical assistance provided by SPC, ACIAR, the World Vegetable Center and FAO in working with project countries to identify strategies designed to reduce use of pesticides in agriculture production.
‘We look forward to your meeting outcomes so we are better able to advise our national governments and regional leaders of appropriate approaches toward reducing usage of pesticides.’
Dr Viliami Fakava, Plant Production and Protection Officer, FAO Sub-regional Office for the Pacific, also extended a warm welcome to delegates, saying their presence is an indication their national governments attach much significance to sustainable development of agriculture. The ICM integrated project with the FAO TCP was implemented in June 2012 with the objective of strengthening capacities of SPC and the national governments of Samoa, Solomon Islands, Tonga and Fiji to develop, introduce and implement strategies that reduce inputs of hazardous pesticides into agricultural systems through the adoption of IPM by farmers and extension staff.
‘FAO is committed to agricultural practices that are environmentally safe, as reflected in the promotion of the Save and Grow approach to produce “more with less” in building healthy ecosystems and our commitment to the use of IPM to reduce dependence on pesticides and increase the use of natural alternatives,’ he said.
FAO defines IPM as ‘the careful consideration of all available pest control techniques and subsequent integration of appropriate measures that discourage the development of pest populations and keep pesticides and other interventions to levels that are economically justified and reduce or minimize risks to human health and the environment’.
Dr Fakava said IPM strategies vary depending on the crop, country, and region, and can even vary within a location, depending on local varieties used and local agronomic practices. ‘IPM can never be delivered in a “package”; it needs to be developed and adapted to fit the local environment.
However, experiences from one area or country may be helpful to set up field studies for testing components that may lead to tolerable pest populations and high yields of good quality produce.’
The ICM project’s multifaceted approach involves plant health clinics (pest and diseases diagnostics), academic research (insecticide resistance), applied research (crop varietal evaluation), and a participatory guarantee scheme (commodity-market supply chain).
Project activities continue with examining import protocols of the bio-pesticide Bacillus thuringiensis (Bt), studies on the regional status of the diamond back moth insecticide resistance and investigating the biological control agent Trichograma chilonis for the management of the large cabbage moth. The biocontrol agent T. chilonis is being sourced from Samoa.
Research work (field collections and bioassays) continue to determine the status of insecticide resistance in diamondback moth populations in Fiji, Samoa, Solomon Islands and Tonga, with the aim to design and implement an insecticide resistance management (IRM) strategy.
Solomon Island project stakeholders continue research into field testing of cultural control methods (adult trapping, disruption of oviposition sites, deployment of physical barriers) for the management of the sliperi kabis flea beetle (Nisotra basselae) in Solomon Islands.
The integrated TCP implementation focus on participatory training of trainers (TOT) and farmer field schools (FFS) as practical application of research activities. FFS is the platform that provides knowledge to participants over one crop cycle in various areas such as insect life cycle, insect damage, how predators and parasitoids attack and feed on their hosts/prey; what cultural management practices are appropriate; seed health and selection; proper land preparation; soil, nutrient, and water management; sanitation; cropping patterns; and use of organic fertilisers in cabbage production and their effect on insects, diseases, weeds and other pests. All other management strategies such as biological, mechanical, physical and chemical control are also studied. Last year TOT and FFS was completed in Samoa and Tonga. The TOT compares two farming systems: ICM (use of biopesticide) and conventional (use of chemicals).
A report on the review of the plant health clinics that was piloted in Solomon Islands in 2013 was presented by Dr Graham Jackson of Terra Circle. The evaluation presented a mixed review of the clinics, with sustainability a major issue of contention. Project countries took on the initiative to implement the plant health clinics and have incorporated them into their work programme in 2014. A concept note is being prepared for submission for additional funding to extend the project to other countries. A set of technical fact sheets on pest problems have been developed, and 140 fact sheets are now online.
Dr Jaw-Fen Wang of the World Vegetable Center is leading research that is evaluating effectiveness of plant elicitors to induce resistance in tomatoes against diseases like tomato late blight. The biochemical elicitor phosphoric acid salt is one of the elicitors being evaluated for enhancing resistance to tomato foliar diseases. Dr Mike Furlong of the University of Queensland is conducting laboratory tests to determine if application of elicitors affects behaviour of natural enemies of the plants such as parasites and parasitoids.
SPC is leading research in two areas: evaluating effectiveness of plant derived pesticides (goat weed, neem, derris, marigold and oleander) on diamond-back moth and large cabbage moth, and trials of the use of the cover legume mucuna with taro as a replacement weedicide; mucuna is also known to fix nitrogen to improve soil health.
– SPC