Agriculture Reference
In-Depth Information
needs through exchanges with other farmers and selection in their fi elds.
In the case of OA, genetically diverse varieties can benefi t from on-farm
participatory plant breeding [5-9] in addition to classical breeding, even
when classical breeding is conducted under organic conditions.
Given the growing need for historical and landrace (farmer) varieties
bred on-farm [10], the EU needed more scientifi c information on how such
varieties evolve and the associated legislative issues (among others DUS
criteria), since seed legislation was developed for homogeneous varieties
in a conventional agriculture framework [1]. In the literature, results can
be found on the evolution of farmer varieties based on genetic markers, for
instance [11-13], but there are few results based on phenotypic traits that
are of direct relevance to the farmers [12,14]. Thus, in the EU, research pro-
gramme Farm Seed Opportunities [15], experiments over three years stud-
ied on-farm cultivation and selection in contrasting environments of farmer
varieties of wheat, maize, bean and spinach. In this paper, we report on the
experiments with spinach (
Spinacia oleracea
L.), an allogamous vegetable
species. In addition, a similar trial on bread wheat, an autogamous crop spe-
cies, is reported [10]. Results to be published later on maize, an allogamous
crop species, will enable us to have more insights on the short-term evolu-
tion of farmer varieties, and their potential adaptation to farmers' conditions.
Specifi cally, our study tries to address the following questions: (1) Does
farm cultivation and selection over two years lead to statistically signifi cant
phenotypic changes in spinach farmer varieties? To what extent have the
tested varieties diverged in a two-year timeframe? Are varieties still distinct
after on-farm cultivation? (2) If changes are observed, how can we relate
them to the cultivation and type of selection experienced by the different va-
rieties? (3) Are there differences of within-variety diversity levels between a
F1 hybrid control and the farmer varieties under organic conditions?
12.2 MATERIALS AND METHODS
In our study, phenotypic changes of different spinach (
Spinacia oleracea
L.) population varieties were explored during an experiment over three
years, from 2007 to 2009. The plants were cultivated and selected by or-
ganic farmers in contrasted environments (two farmers in Western France
