Proceedings
of the XLVI Italian Society of Agricultural Genetics - SIGA Annual Congress
Giardini Naxos, Italy - 18/21
September, 2002
ISBN 88-900622-3-1
Poster Abstract - 4.41
DIVERSITY
OF SEED STORAGE PROTEIN PROFILES IN ITALIAN POPULATIONS OF LENTIL (LENS
CULINARIS MEDIK)
PIERGIOVANNI
A.R., TARANTO G.
CNR –
Istituto del Germoplasma, Via Amendola 165/A, 70126 Bari
genetic
diversity, germplasm, landraces, protein polymorphism, SDS-PAGE
In
Italy lentils have been cultivated since ancient times. This has allowed the
evolution, over the time, of populations well adapted to the pedo-climatic conditions
of each region. In recent decades, lentil cultivation has been progressively
abandoned. Nowadays this pulse survives in marginal areas as well as in some
small islands, but the local populations still cultivated are threatened of
disappearance. Due to the low economic value of lentil, the Italian germplasm
of this pulse has been little investigated. The objectives of this study are:
1) to evaluate the variation of seed storage proteins within and among 44
Italian populations; 2) to identify the geographical areas and the populations
showing the highest diversity indices. The studied populations come from
Central Italy, Southern Italy and some small islands. The collection comprises
large and small-seeded types. The seed storage proteins were studied by
electrophoresis (SDS-PAGE), 518 seeds were singly assayed. The genetic
diversity within each population was estimated as Shannon-Weaver Index (SWI);
the distance between pairs of the most appreciated populations was calculated
according to the Bhattacharyya formula (Bd). Variation in the presence/absence
and relative staining intensity of several bands was detected within and among
the populations. The protein polymorphism within the populations was a general
rule with only few exceptions. Small-seeded types resulted more polymorphic
than the large ones. It were identified 31 proteins profiles showing different
frequencies (from 17.5% to less than 0.5%). The populations from Central Italy
constituted the most variable fraction of the collection. At the opposite,
populations from small islands near Sicily showed very similar profiles.
Moreover, lentils from Pantelleria and Linosa showed the lowest SWI (0.000).
The highest SWI was detected for the lentil from S.Stefano in Sessanio
(Abruzzo) (SWI=0.082). Lentil from Castelluccio di Norcia (Umbria), known for
the very high morphological diversity of seeds, showed intermediate
intra-population variation (SWI=0.049).
The
differentiation among the 9 most appreciated populations included in this study
was also investigated. These populations resulted well differentiated. The
Bhattacharyya distance calculated between pairs of these populations ranged
from 5.04 to 26.32. Lentil from S.Stefano was the most divergent showing Bd
comprised from 16.20 (S.Stefano-Villalba) to 25.81 (S.Stefano-Ventotene). The
appreciable genetic diversity detected in this collection states the importance
of Italian lentil germplasm and support the need of urgent initiatives to
safeguard this germplasm. Moreover, the presented results may provide useful
information for its utilisation in breeding programme of lentil.