Naslov
Ongoing research on ash dieback in Croatia

Autori
Diminić, Danko ; Milotić, Marno ; Kajba, Davorin

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, pp prezentacija, znanstveni

Skup
EMN 17th annual meeting and EPPO 13th workshop on EPPO diagnostic protocols for regulated pests (Fungi)

Mjesto i datum
Budimpešta, Mađarska, 06.05.2014. - 09.05.2014

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
common and narrow - leaved ash; dieback; Chalara fraxinea; clonal seed orchards; phenological monitoring; flushing phases.

Sažetak
First record of significant dieback on common ash (Fraxinus excelsior L.) was in Poland 1992. From then, this new desease has spread throughout the European continent. The simptoms of this desease are caused by the phytopatogenic fungus Chalara fraxinea T. Kowalski which was first described in 2006. In Croatia the desease was first recorded in may of 2009 at the mauntain area of Gorski kotar. To this day the desease was recorded also in the regions Lika, Žumberak and Hrvatsko zagorje. Chalara fraxinea was also recorded on narrowe - leaved ash (Fraxinus angustifolia Vahl.) in the regions of Međimurje, Podravina, Jastrebarski lugovi and Pisarovinski lugovi. The complete biology, means and time of the infection is not yet been fully understood. In 2011, the teleomorfic stage of the fungus Hymenoscyphus pseudoalbidus Queloz, Grünig, Berndt, T. Kowalski, T.N. Sieber & Holdenr has been discovered. This stage of the fungus is developing on the rachises of the fallen common ash leaves. In Croatia, narrow-leaved ash (Fraxinus angustifolia Vahl) is widely distributed in the Pannonian lowland area, along the rivers Sava, Drava and Dunav. The greatest portion of its genetic variability is localized through Sava river region. In this area we have established two clonal seed orchards. First clonal seed orchard of narrow leaf ash (Nova Gradiška) was established in 2005 in the area of 3.5 ha with 56 clones. The grafts were planted with 4 × 4 m spacing. Second clonal seed orchard of narrow leaf ash (Čazma) was established in 2007 in the area of 7, 3 ha, and the grafts were planted with 5 × 5 m spacing and it contains 50 clones. Through the period of two years we observed the phenological differences in monitoring the six flushing phases on different clones with four repetitions, on wich we based our strategy to determine interclonal and intraclonal discrepancies and variations. Also the temperature and humidity was measured in the seed orchards and compared with the results of the flushing phases. In this period seed orchards where continuously monitored and checked for the presence of Chalara fraxinea, but it was not confirmed, and on the clones there were no simptoms that would indicate its presence. With the results gathered from this monitoring we where able to determine and classify clones into early and late flushing groups, which has a high practical value not only for seed orchard protection and maintaning the high vitality of the clones, but also for the distribution and application of seed from the seed orchard. Furthermore for some clones we determined substantial intraclonal variations in flushing phases.

Izvorni jezik
Engleski

Znanstvena područja
Šumarstvo

POVEZANOST RADA