The first occurrence of stem canker on oilseed rape caused by Leptosphaeria biglobosa in Serbia

Abstract

In October 2010 the occurrence of the stem canker symptoms in rapeseed was observed at the locality Rimski Šančevi in Serbia. Several strains of fungi were isolated from the stem. Morphological characteristics of the isolates were studied on a PDA medium at 25±1oC: growth rate, colour, shape and appearance of colonies and the edge of the colony, the pigment, size, colour and shape of pycnidiospores and pycnidia in 10 isolates (isolated in Serbia K-111, IK-112, K-113, K-114, K-115, K-116, IK-117, K-118, K-119, and K-120). All tested strains had fast growth, the regular form of colonies and poor sporulation on nutrient medium. Pycnidiospores are unicellular, hyaline, and mostly straight, with or without a drop of oil. Molecular identification was performed by the application the PCR technique using primers PN3/PN10. In addition to these 10 isolates, two reference strains obtained from the Centre for Agricultural Studies, Rothamsted, UK, which are marked with L. m (Leptosphaena maculanS), L. b (Leptosphaeria biglobosa) and 7 reference isolates originating from Serbia, which are marked K-7, St-16, GS-25, L-5, C-3, LJ-2, S-1 were used. On the basis of DNA amplification with primers PN3 and PN10 tape length was about 580 bp for isolates (L.b, IK-111, K-112, K-113, K-114, K-115, K-116, K-117, K-118, K-119, K-120) while that was 560 bp for other group of isolates (L.m, K-7, St-16, GS-25, L-5, C-3, LJ- 2, S-1).This study showed that 10 isolates (K-111, K-112, K-113, IK- 114, K-115, K-116, K-117, K-118, K-119, K-120) isolated from the stem of rapeseed belong to the species Leptosphaeria biglobosa.

U oktobru 2010. pojava simptoma raka stabla na uljanoj repici je uočena na lokalitetu Rimski šančevi u Srbiji. Nekoliko izolata gljive je izolovano iz stabla. Morfološke karakteristike 10 izolata izolovanih u Srbiji su proučene na PDA podlozi, na temperaturi 25±1 oC : rast, boja, oblik, izgled kolonija ivice kolonije, lučenje pigmenta, veličina, boja i oblik piknospora i piknida K-111, K-112, K-113, K-114, K-115, K-116, K-117, K-118, K-119, K-120. Svi testirani izolati imaju brz porast, pravilan oblik kolonija i slabu sporulaciju na hranljivoj podlozi. Piknospore su jednoćelijske, hijalne, uglavnom prave, sa ili bez kapi ulja. Molekularna identifikadja je urađena upotrebom PCR tehnike korišćenjem prajmera PN3/PN10. Pored ovih izolata, dva referentna soja su dobijena iz Centra za poljoprivredna istraživanja Rothamsted, Ujedinjeno Kraljevstvo, i označeni sa L. m {Leptosphaeria maculans), L. b (Leptosphaeria biglobosa) i 7 izolata poreklom iz Srbije, označenih sa K-7, St-16, GS-25, L-5, C-3, LJ-2, S-1. Na osnovu DNK amplifikacije sa prajmerima PN3 i PN10 dužina je oko 580 bp (L.b, K-111, K-112, K-113, K-114, K- 115, K-116, K-117, K-118, K-119, K-120) dok kod drugih izolata (L.m, K-7, St-16, GS-25, L-5, C-3, LJ- 2, S-1) je 560 bp. Ova proučavanja su pokazala da svi ispitivani izolati (K-111, K-112, K-113, K-114, K-115, K-116, K-117, K- 118, K-119, K-120) izolovani iz prizemnog dela stabla uljane repice pripadaju vrsti Leptosphaeria biglobosa.