No abstract

Hawthorns (Crataegus) are used for horticultural and medicinal purposes. They can be used as a rootstock for grafting. They are graft compatible with Mespilus L. (medlar), pear (Pyrus L.), and quince (Cydonia Mill.). Moreover, they are traditionally used for their cardio-protective benefits and antioxidative potential. The pharmacological importance of Crataegus is attributed mainly to components such as flavonoids, procyanidin, aromatic acid, and cardiotonic amines. In the present investigation, 70 accessions of Crataegus monogyna Jacq. originating from natural populations in the Kashan region, Iran, were characterized using a set of 49 morphological traits. An analysis of variance showed a high variability in the evaluated accessions and significant differences were found between them for most of traits measured. Results from simple correlation analysis showed significant positive and negative correlations among certain important characteristics. Leaf length was positively and significantly correlated with leaf width; fruit weight was positively and significantly correlated with fruit length and width. Fruit flesh weight showed high positive correlations with fruit width and weight and negative correlation with seed number. A principal component analysis showed high discrimination capabilities of variables measured. Cluster analysis revealed a grouping of accessions in three major clusters, where clusters with large number of accessions contained sub-clusters. The present findings indicated that the studied hawthorn germplasm must be conserved as valuable genetic resources.

The damage to pear and plum buds was investigated in Mashhad, after a period of unusually warm weather for a few days in March 2013 followed by a sudden drop in temperature to -12°C. Frost damages of vegetative and reproductive buds and spur-part below the buds of pear and plum cultivars were investigated based on visual observations. The following pear (Pyrus communis L.) cultivars were investigated: William's, Bell de june, Ida, Spadona, Koshia, Domkaj, Dare Gazi, Mohamad Ali, Boheme, Shekari, Ghodumi and one Asian pear (Pyrus serotina Rehd.). Japanese plum (P. salicina L.) included 'Shiro', 'Shams', 'Computi' and European plum (Prunus domestica L.) included 'Stanley', 'Early Santa Rosa', 'Late Santa Rosa', 'Shablon' and 'Black Diamond'. Electrical conductivity (EC) and proline content were measured in reproductive buds. It was discovered that visual damages were different between cultivars, as the vegetative pear bud of 'Ghodumi' suffered the most damage and all parts of 'Late Santa Rosa' were the most susceptible in plum cultivars. On the other hand, 'Computi' had the most resistant reproductive bud and no damage was observed in the other parts. The EC and proline content of 'Dare Gazi' were the highest despite the fact that high proline content did not show high resistance, which was related to the phenological stage of 'Dare Gazi'.Ke y wor d s: electrical conductivity; frost damage; proline content; visual observation