Izazovi kontrole ramulariozne pegavosti ječma

Abstract

Ramulariozna pegavost ječma je prvi put preopoznata u Evropi kao ekonomski značajno oboljenje tek 80-ih godina XX veka, iako je opisana u Italiji još 1889. Prouzrokovač ramularioizne pegavosti ječma je gljiva Ramularia collo-cygni koja je dobila naziv na osnovu izgleda konidiofora koji podsećaju na vrat labuda. Ramularia collo-cygni je opisana kao ekomski značajan patogen još u Novom Zelandu, Argentini i istočnoj i zapadnoj obali Kanade. dovodeći do gubitaka prinosa i do 35 %. Ramularia collo-cygni se prvenstveno prenosi semenom, mada sekundarni izvor infekcije mogu činiti i spore koje se šire vazdušnim strujama. Ramularia collo-cygni je endofitna gljiva, i u uslovima stresa biljke dobija patogena svojstva produkcijom rubelina (A–E) od čega rubelini B i D dovode do razaranja membrane i nekroze tkiva domaćina. S obzirom da je Ramularia collo- cygni prouzrokovač relativno novog oboljenja i da testiranje semena ječma u prometu nije vršeno na njeno prisustvo, postoji rizik širenja ove bolesti na područja u kojima nije bila prisutna. Prvi simptomi ramularaiozne pegaovsti ječma u Srbiji primećeni su u nešto slabijem intenzitetu 2008. i 2009. godine na lokalitetu Rimski Šančevi, dok je prva jača pojava na sortama ozimog ječma zabeležena i opisana od strane Jevtića i sar. (2016) na više lokaliteta u Srbiji proizvodne 2015/2016.

Ramularia leaf spot of barley was not recognized in Europe as an economically significant disease until the 80s of XX, although the causal agent Ramularia collo-cygni was identified as early as 1889 in Italy. The name of Ramularia collo-cygni is derived from the special swan neck shape of the conidiophores. Ramularia collo-cygni has been described as an economically significant pathogen in New Zealand, Argentina, and Canada causing yield losses of up to 35%. It is primarily considered a seed-borne pathogen, although it could also be transmitted as air-borne conidia. Ramularia collo-cygni is known as an endophytic fungus, but under conditions of plant stress, it gets pathogenic properties by producing rubellins (A – E), of which rubellins B and D lead to membrane destruction and host tissue necrosis. Given that Ramularia collo-cygni is the causal agent of a relatively new disease, and that testing of seed for the presence of Ramularia collo-cygni is not required as a statutory seed test, there is a risk of disease spreading in the areas where it was not present. The first symptoms of Ramularia leaf spot in Serbia were observed in 2008 and 2009 at the locality Rimski šančevi, leading to more prominent occurrences in several locations in Serbia during the 2015/2016 growing season.