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The 'Romanesco' globe artichoke is of substantial economic importance for Italy, its major world producer. The widespread adoption of single early uniform micropropagated clones has led to erosion of local genetic resources. In an attempt to characterise landrace diversity for future breeding activities and/or germplasm conservation, a set of 19 clones derived from plants cultivated in traditional areas of Latium region were typed using a combination of morphological traits (UPOV descriptors) and DNA markers (AFLP and ISSR). Principal Component Analysis and significant correlations among some of the morphological traits showed that a reduced number of descriptors could be used efficiently to discriminate between the clones. Stepwise regression analysis identified a number of significant and consistent associations between certain morphological characters and marker loci. Heritability for important economic traits were computed; moreover, remarkable clones for future breeding activities were recognized. The variability present within the farmers' fields is an important factor in the design of a rational strategy of in situ germplasm conservation. AbbreviationsTNH Total number of heads E Time of appearance of the central head LH1 Length of the first order head on the lateral shoots NH Number of primary and secondary heads NH1 Number of first order heads NH2 Number of secondary heads WH1 Weight of the primary heads WH2 Total weight of the secondary heads DH1 Diameter of the first order head on the lateral shoots LCH Length of central head WCH Weight of the central head DCH Diameter of the central head MSL Main stem length PH Plant height P. Crinò and R. Tavazza have contributed equally to the work.

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Glasshouse evaluations of rootstocks of melon for resistance to Didymella bryoniae were conducted on different cucurbits previously selected as resistant or partially resistant to race 1,2 of Fusarium oxysporum f. sp. melonis. Cucumis anguria, C. ficifolius, C. figarei, C. metuliferus, C. zeyheri and Benincasa hispida showed a very high degree of resistance to D. bryoniae both on leaves and stems. Among the commercial rootstocks, Cucurbita hybrids ELSI, ES 99‐13, RS 841, displayed a similar level of resistance. Stem inoculation of three cucurbit species grafted with susceptible melon cv. Proteo determined the occurrence of limited symptoms, but the lesions remained confined in the rootstock not affecting the grafted plant. Cultivation of susceptible melon cultivars grafted on resistant rootstocks may represent an efficient method for controlling Didymella crown rot and Fusarium wilt.

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