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The RFLP technique was used to establish a reliable diagnostic method for 18 Pratylenchus species: Pratylenchus agilis, P. bolivianus, P. brachyurus, P. coffeae, P. crenatus, P. fallax, P. goodeyi, P. loosi, P. mediterraneus, P. neglectus, P. penetrans, P. pratensis, P. pseudocoffeae, P. scribneri, P. subranjani, P. thornei, P. vulnus and P. zeae. The polymerase chain reaction (PCR) amplified the ITS regions from all species and populations examined and revealed large differences in length, ranging in size from approximately 900 to 1250 bp. The rDNA fragments were digested with five restriction enzymes (CfoI, DdeI, HindIII, HpaII, and PstI). All Pratylenchus species can be differentiated from each other by a combination of at least two enzymes. CfoI differentiated all nematode species with the exception of P. fallax, P. penetrans and P. pseudocoffeae. P. fallax was further separated by a DdeI restriction, and P. pseudocoffeae by a PstI digestion. Intraspecific RFLP were observed. Upon CfoI, DdeI, HindIII, or HpaII digestion, it was possible to separate the three P. coffeae populations studied from each other. La technique RFLP a été utilisée pour créer une méthode fiable de diagnostic pour 18 espèces de Pratylenchus: Pratylenchus agilis, P. bolivianus, P. brachyurus, P. coffeae, P. crenatus, P. fallax, P. goodeyi, P. loosi, P. mediterraneus, P. neglectus, P. penetrans, P. pratensis, P. pseudocoffeae, P. scribneri, P. subranjani, P. thornei, P. vulnus et P. zeae. La réaction de polymérisation en chaîne (PCR) a amplifié les régions de l’ITS pour toutes les espèces et populations étudiées et a mis en évidence de grandes différences dans la taille des gammes de longueur, de 900 à 1250 bp approximativement. Les fragments de rDNA ont été digérés à l’aide de cinq enzymes de restriction (CfoI, DdeI, HindIII, HpaII, and PstI). Toutes les espèces de Pratylenchus ont pu être différenciées les unes des autres par une combinaison d’au moins deux enzymes. CfoI a différencié toutes les espèces à l’exception de P. fallax, P. penetrans et P. pseudocoffeae. P. fallax a été ultérieurement séparé par une restriction DdeI, et P. pseudocoffeae par une digestion PstI. Des RFLP intraspécifiques ont été observés. Par les digestions CfoI, DdeI, HindIII, ou HpaII, il s’est révélé possible de séparer les unes des autres les trois populations étudiées de P. coffeae.

Trials were established at Aula Dei Experimental Station (EEAD-CSIC, Zaragoza, Spain) to assess graft compatibility between peach cultivars [Prunus persica (L.) Batsch] and new Prunus spp. rootstocks or selections. Peach cvs. `Catherina' and `Tebana' and nectarine cvs. `Big Top' and `Summergrand' were grafted on peach seedlings, plum rootstocks, almond × peach hybrids, and other interspecific rootstocks. Part of the evaluated material belongs to the EEAD-CSIC selection program, which has showed good adaptation to Mediterranean growing conditions. Other rootstocks such as Bruce, Evrica, Hiawatha, Ishtara, Tetra, and Krymsk-1 have been recently introduced in Spain. A peach and a plum source, GF 677 and Adesoto 101, respectively, were used as compatible reference rootstocks. Both are widely used for peach and nectarine production in the Mediterranean area.

In this study, the field performance of Adara, CAB 6P, Gisela 5, MaxMa 14, Saint Lucie GF 64 (SL 64), Saint Lucie GF 405 (SL 405), and Tabel-Edabriz rootstocks, grafted with two sweet cherry cultivars ('Stark Hardy Giant' and 'Van', Prunus avium L.), were compared after seven years of planting on a calcareous clay-loam soil. The leaf and shoot mineral elements analysed were N, P, K, Ca, Mg, Fe, Mn, Zn, Na and Cu. In the case of both cultivars, tree vigour and cumulative yield were highest on Adara, whereas yield efficiency was greater on Gisela 5. All rootstocks induced low leaf

17The field performance of fifteen peach and plum based rootstocks of different vigour 18 (Adesoto, Evrica, Garnem, GF 677, HM-2, Krymsk