I agree that a lot more should be done to help Pacific agricultural producers – particularly as agriculture is the main source of livelihoods. How that might be done requires a lot of thought. Better resourcing agricultural extension offices may be part of the story, but there’s a lot more to it (especially if these institutions have governance weaknesses – as you identify). I think community farmers make great produce, but they often lack capital (can government/donors/NGOs help mitigate the costs of finance?) and information, particularly around market opportunities and expectations (can government/donors/NGOs help with this ‘market failure’ of poor access to information). Community farmers also face huge risks when they consider innovation – new crops for consumption or sale (can government/donors/NGOs help mitigate risks through pilot agricultural programs, through concessionary access to insurance?)

See here for a paper I recently published on opportunities for agricultural development in the Pacific.
Growing Island Exports: High Value Crops and the Future of Agriculture in the Pacific
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2371452

The experience of agricultural support programs in Taveuni, Fiji, offers some guide for other island communities, and governments/Donors/NGOs intending to help communities improve agricultural output. See here for an excellent report on the Tutu Rural Training Centre:
http://www.aglinks.net/content/tutu-rural-training-center-training-youths-self-employment-agriculture