Plant breeding for organic and sustainable, low-input agriculture

Genetic diversity of an emmer population grown under organic farming in Central Italy
Renzo Torricelli, Mario Falcinelli
Plant Biology, Agro-environmental and Animal Biotechnology Dept., University of Perugia,
Italy
Emmer (Triticum dicoccum Schubler, 2n= 4x= 28) is a predominantly self pollinated crop
widespread throughout the Mediterranean Basin. The cultivation of this hulled wheat species has
survived only in a few marginal mountainous areas of central and southern Italy. In central Italy
the area cultivated with emmer increased during the last decade due to renewed interest in
natural and healthy food and in organic agriculture. Since this species has not been bred with
modern strategies, landraces are the only genetic material available. Hence the acreage of emmer
has increased especially in marginal areas because it is well-suited to low input agronomic
systems. Emmer landraces are still maintained and managed on-farm because of their resistance
to harsh climatic conditions, cultural reasons, or organoleptic aspects which make them highly
valuable. The objective of this study was to characterize the genetic structure of a central Italian
landrace of emmer named “Monteleone di Spoleto”. 106 randomly chosen spikes were collected
from an organic field in Monteleone di Spoleto, 1000 m a.s.l. (Perugia – Italy). The physiological
and morphological traits of progenies of each genotype were evaluated. The following
characteristics were recorded: growth habit (GH), stem colour (SC), heading time (HT), plant
height (PH), seed yield/plant (SY) and score of naked seed (SNS). Univariate and multivariate
analysis showed wide genetic diversity within landrace of Monteleone di Spoleto emmer. The
Principal Component Analysis (PCA) showed that the first three components accounted for
34.8%, 18.4% and 18.1% of variance, respectively (cumulative = 70%). On the basis of the
eigenvector values, the traits responsible for maximum separation along the first component,
were: heading time, plant height and seed yield/plant. The PCA has allowed to group the 106
lines of emmer in a restricted number of different families. These homozygous families differ
one another for at least one trait. We concluded that the emmer “Monteleone di Spoleto” can be
considered like a natural composite variety originated by continuous on farm conservation; it is
genetically heterogeneous and is well adapted to the local environmental conditions.
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