Morfološka i molekularna karakterizacija i identifikacija gljive uzročnika raka stabla uljane repice u Srbiji

Abstract

Rak prizemnog dela stabla ekonomski je vaţno oboljenje uljane repice u Evropi, Australiji i Severnoj Americi. Ovu bolest prouzrokuju dve vrste: Leptosphaeria maculans (Desm.) Ces. de Not (anamorfni stadium Phoma lingam (Tode ex Fr.) Desm. i Leptosphaeria biglobosa Shoem and Brun. Štete od L. maculans u Kanadi godišnje prelaze 30 miliona dolara, dok u Velikoj Britaniji, u uslovima povoljnim za razvoj patogena, štete mogu biti i do 56 miliona evra. Gljiva prouzrokuje velike štete i u Australiji a prisutna je i u Africi, Juţnoj Americi i Aziji. Iako se Leptosphaeria maculans nalazila na listi karantinskih patogena u bivšoj Jugoslaviji , još 1965. godine je registrovana kao parazit karfiola u okolini Splita. Tokom 1983. konstatovana je u mnogim proizvodnim regionima Jugoslavije. Patogen je sa uljane repice izolovan 1987/88. a tokom 1995. godine u Republici Srbiji izolovan je sa semenskog i konzumnog kupusa. Tokom 2005. i 2006. godine parazit je izolovan u svim proizvodnim područjima uljane repice u Vojvodini. Iako je parazit kod nas izolovan još 1987/88, zatim 1995. godine i tokom 2005/06, ni patogen niti oboljenje koje prouzrokuje na uljanoj repici nisu detaljnije proučavani. Zbog toga su sprovedena morfološka i molekularna istraţivanja 119 izolata gljiva izolovanih sa uljane repice u našoj zemlji da bi se dobili pouzdani podaci o etiologiji suve truleţi korena i raka stabla uljne repice i identifikovali uzročnici ovog značajnog oboljenja. Proučene su morfološke, patogene i molekularne karakteristike 119 izolata izolovanih tokom 2008/10. godine u regionu (Vojvodina) Srbije. Pored izolata iz naše zemlje u ovim istraţivanjima su korišćena i dva izolata iz Velike Britanije, kao referentni izolati. Svi proučavani izolati na podlozi od krompira (PDA) obrazuju plodonosna tela  piknide sa piknosporama. Piknospore su jednoćelijske, hijalne, uglavnom prave, sa ili bez kapi ulja na krajevima kod svih izolata. Od 119 izolata 8 izolata (K-111, K-112, K-113, K-114, K-115, K-116, K-117 i K-118) imaju brz i pravilan porast micelije na PDA podlozi, obrazuju ţutomrki pigment, za razliku od ostalih koji se sporo razvijaju, ne obrazuju pigment, a ivice kolonija su nepravilnog oblika. Svi izolati obrazuju belu do prljavobelu miceliju..

Stem canker of oilseed rape is economicaly important desease in Europe, Australia and North America. This disease is caused by two species: Leptosphaeria maculans (Desm.) Ces. de Not (anamorphic stadium Phoma lingam (Tode ex Fr.) Desm. i Leptosphaeria biglobosa Shoem and Brun. Damage caused by L. maculans in Canada annually exceeds $ 30 million, while in the UK, under conditions favorable for pathogen development, the damage could be as high as 56 million. The fungus causes severe damage in Australia too and it is present in Africa, South America and Asia. Although Leptosphaeria maculans is on the list of quarantine pathogens in the former Yugoslavia, in 1965. it is registered as cauliflower parasite around Split. During the 1983rd was found in many manufacturing regions of Yugoslavia. The pathogen was isolated from oilseed rape in 1987/88. and during 1995. has been isolated from cabbage. During 2005 and 2006 parasit has been isolated in all production areas of oilseed rape in Vojvodina. Although parasite was isolated in 1987/88, then again in 1995. and during 2005/2006, Iako je parazit kod nas izolovan još 1987/88, zatim 1995. godine i tokom 2005/06, either pathogen or disease that causes on the oilseed rape were not investigated further. Therefore, morphological and molecular studies of 119 isolates of fungi isolated from oilseed rape in our country were carried out in order to obtain reliable data on the etiology of dry root rot and stem canker of oilseed rape and to identify the causes of this important disease. Were studied morphological, pathogenic and molecular characteristics of 119 strains isolated during 2008/10. in the region (Vojvodina) of Serbia. In addition to isolates from our country in these studies were used and the two isolates from the UK, as well as reference strains. All studied isolates on a potato medium (PDA) form fruiting bodies pycnidia with pycnospores. Pycnospores are unicellular, hyalic, mostly straight, with or without a drop of oil on the ends in all isolates. Eight isolates out of 119 (K-111, K-112, K-113, K-114, K-115, K-116, K-117 i K-118) have quick and proper mycelia growth on PDA medium, form yellow-brownish pigment, unlike others who are slow to develop, do not form the pigment and the edges of colonies are irregular in shape...