Proceedings of the XLV Italian Society of Agricultural Genetics - SIGA Annual Congress

Salsomaggiore Terme, Italy - 26/29 September, 2001

ISBN 88-900622-1-5

Poster Abstract

GENETIC DIVERSITY IN CULTIVATED POPULATIONS OF CAPSICUM ANNUUM L., ECOTYPE ‘CUNEO’

LANTERI S.*, ACQUADRO A.**, DI LEO I.**, QUAGLIOTTI L.*, PORTIS E.**

* Dipartimento di Scienze Agronomiche e Genetica Vegetale, Università degli Studi di Sassari, Via E. De Nicola , 07100 Sassari

lanteri@uniss.it

** DI.VA.P.R.A., settore Genetica Agraria, Università degli Studi di Torino, Via L. da Vinci 44, 10095 Grugliasco, Torino

portis@agraria.unito.it

In Piedmont (north-west Italy) sweet pepper is traditionally cultivated. Among the high number of commercial and local cultivars grown, the ecotype ‘Cuneo’ deserves particular attention because of its rusticity, late production and the quality of the berries, e.g. thickness, weight and taste.

We use the term ‘Cuneo’ ecotype instead of cultivar, since no standard and homogeneous characteristics are established for it and a well defined ideotype does not exist. Each farmer, in fact, produces seeds by himself and follows personal criteria of selection.

Five populations, cultivated in as many locations in the south of Piedmont, were identified and evaluated for polymorphism using Random Amplified Polymorphic DNA (RAPD) markers.

AMOVA (Analysis of Molecular Variance) gave highly significant differences between populations (43.9% of the total genetic diversity); substantial within-population variation was also detected (56.1% of the total genetic diversity). The genetic variability within the ecotype ‘Cuneo’ is presumably a consequence of different selection criteria adopted by farmers as well as of genetic contamination with commercial cultivars grown in the same area.

Two artificial populations, including the genetic variation detected, were set up and grown:

I in the experimental fields of the DIVAPRA, Agricultural Genetics (University of Turin), Piedmont;

II in the experimental fields of the Department of Agricultural Science and Plant Genetics (University of Sassari), Sardinia.

The artificial populations have been characterized for morphology, production and by means of RAPD, AFLP, ISSR and SSR markers. They represent the starting material for:

I defining the ‘Cuneo’pepper ideotype,

II assessing its adaptability to Sardinian environment,

III applying breeding activities aimed at providing selected material to farmers.

Furthermore, by evaluating molecular variation over time, it will be possible to assess the effect of different environmental conditions on self and out-crossing rates and on genetic composition of the populations, so that to identify the most suitable strategies for ‘in situ’ preservation of the ‘Cuneo’ germplasm.