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 - 3.05

LOCAL POPULATIONS OF PHASEOLUS VULGARIS L. AND P.COCCINEUS L. FROM CENTRAL ITALY. I: VALLE PELIGNA AND VAL ANIENE

PIERGIOVANNI A.R., TARANTO G., LOSAVIO F.P., PIGNONE D.

CNR – Istituto del Germoplasma, Via Amendola 165/A, 70126 Bari

common bean, runner bean, genetic diversity, germplasm, sustainable agriculture

Autochthonous populations of many crops, selected over the time by local farmers, survive under cultivation in several Italian regions. Several studies indicated that the marginal areas located along the Appenninic ridge are rich of this autochthonous germplasm. These are areas where agriculture is not intensive, possibly for unfavourable agro-climatic conditions, but is mainly carried on for family consumption. The old populations there conserved are threatened of disappearance in the immediate future, as a consequence of many causes, especially land abandon. The collection, characterisation, evaluation and promotion of the local populations is essential to avoid their disappearance and to increase their on-farm survival, in the environments of their original adaptation. The proposal of old populations as niche products is reliable especially for those agro-biotypes carrying agronomic and nutritional traits which can support their commercialisation.

In the present study a total of twenty-two populations were studied: eighteen, nine each from Valle Peligna (Abruzzo) and Val Aniene (Lazio), were common beans (Phaseolus vulgaris L.), while four, one from Valle Peligna and three from Val Aniene were runner beans (P. coccineous L.). One of the problems encountered is that often different ecotypes may be named with the same name, or that different names refer to genetically similar materials. The present investigation also attempts to give an answer to this problem.

Eighteen traits relative to the plant and seed morphology were recorded based on IPGRI descriptors. The variation of phaseolin and lectin patterns within and among the populations were studied by electrophoresis (SDS-PAGE). Moreover, parameters related to dry seed consumption (hydration index, cooking time, coat percentage, etc.) were also considered.

The comparative analysis indicated that the climbing habit is prevalent, in both areas (14 populations); two populations showed a mixture of bush and climbing plants. Seed colour was generally uniform white or light brown, and five populations were brown striped. Large-seeded types (100 seeds weight more than 50 g) were predominant with the exception of the populations ‘A pisello’ (36.9 g) from Raiano (Valle Peligna), ‘A pisello peligni’ (40.2 g) from Sulmona (Valle Peligna) and ‘Pallini’ (42.0 g) from Vallepietra (Val Aniene). Intra-population variation of one or more characters (seed shape, seed colour, phaseolin and lectin profile) was frequently observed. On the bases of the collected data the populations of common bean are tentatively classified in races according to Singh et al. (1991).

The populations of P. coccineous showed to be very similar for plant and seed morphological traits. All showed white and large seeds (weight 100 seeds ranging from 148 g to 180 g). The populations from Valle Aniene exhibited intra-population diversity of the electrophoretic prattern.

These results are to be considered preliminary, since based on a limited number of samples and sampling is still ongoing in these areas. New finding cannot be excluded since often farmers cultivate only few plants of the rare ecotypes for their own consumption and the more farmers are visited the higher the probability of new interesting findings.