Participatory plant breeding (PPB) is now commonly used for breeding organic varieties. Colley et al, 2021 lists nearly 50 current or recent PPB projects in developed countries; almost all are with organic growers. The important reasons for this mostly fit around the not-for-much-profit, sharing ethos of organic organisations. They tend to like working in a participatory fashion with their partners and dislike technologies which adversely affect seed sovereignty. Thus, they do not want to link with plant breeders working for with-profit companies needing ownership of varieties. PPB requiring their breeders to give breeding material to their partners before the final variety is selected actually fits well with their ethos. Organic growers also often belong to an association, which makes it easy to link with them.
Organic seeds also provide a small market, attractive only to small seed companies. They need the seed to be uncomplicated to produce and the open pollinated varieties created by PPB suit them. Organic organisations are also likely to be poorly funded and PPB is cheaper than conventional breeding because their grower partners have the land and other facilities needed for testing large numbers of early forms of new varieties.
They follow a similar methodology to that used by PPB projects in developing countries. The following examples are therefore just a few showing their general characteristics. In all cases, much of the plant selection is done during farmer field days examining trials on organic farms.
The major driving force behind a Dutch organic potato PPB project, Bio-Impuls was a lack of potato varieties that are resistant to late blight so organic growers couldn’t grow the susceptible varieties grown commercially using a fungicide-spraying regime. The Dutch Louis Bolk Institute coordinates this programme, working closely with Wageningen University to include modern sources of natural resistance to blight.
In Germany, the University of Kassel collaborated with organic growers (The Organic Outdoor Tomato Project) to develop late blight-resistant varieties of tomato, again using newly-discovered sources of natural resistance. My favourite of their varieties, Primabella, was a clear winner against several commercial modern varieties in a small test I did on my allotment. Seeds are now widely available in the UK as well as in the EU.
And the Georg-August University at Gottingen collaborated with organic growers to breed a composite variety of field beans (Vicia faba). Growers could save its seeds so it was able to evolve to suit the local conditions, in that way also making use of evolutionary plant breeding (EPB) concepts, and so also have a high and stable yield at a range of sites. Neat!
In the USA, a collaboration between Cornell University plant breeders and organic growers bred a variety of bell peppers known as Peacework. This variety is resistant to Cucumber mosaic virus, a common virus on organic farms because the control of its weed hosts is difficult in organic farming.
Despite this considerable interest in PPB by organic growers, gardeners still tended to be excluded from PPB. Yet there are now a very few recent examples showing how modern communication methods have enabled even gardeners to become involved in PPB.