Morphological and molecular identification of Cercospora apii on celery in Serbia

Abstract

C. apii is one of the most damaging plant pathogenic fungi of celery. During the 2012, samples of celery with typical symptoms of leaf blight were collected on the territory of Veliko Grdaište and their identification is performed using morphological and molecular methods. The pathogenicity test was conducted on healthy plants and all tested isolates caused typical symptoms after inoculation. Conidiophores arising from the stromata formed dense fascicles or single, straight to slightly curved, brown. Conidia are solitary, hyaline and septate (5-13 septa), cylindrical to obclavate, or straight to slightly curved, obtuse at the apex. Truncated and thickened at the base. Fragments of the expected length for the internal transcribed spacer (ITS1/ITS4), calmodulin (CAL-228F/CAL2Rd) and histone (CYLH3F/ CYLH3R) gene were amplified and the obtained sequences showed 100% identity with the C. apii sequences deposited in GenBank.

C. apii predstavlja jednu od najštetnijih fitopatogenih gljiva celera. Tokom 2012. god na teritoriji Velikog Gradišta su prikupljeni uzorci celera sa karakterističnim simptomima pegavosti lista i njihova identifikacija je izvršena pomoću morfoloških i molekularnih metoda. Test patogenosti je obavljen na zdravim biljkama i svi ispitivani izolati prouzrokuju karakteristične simptome nakon inokulacije. Konidiofore iz stroma formiraju zbijene fascikule ili su pojedinačne, prave do blago zakrivljene, smeđe boje. Konidije su pojedinačne, hijalinske i septirane (5-13 septi), cilindrične do blago sužene na jednoj strani ili prave do blago zakrivljene i zatupaste na vrhu. U osnovi su zasečene, skoro kvadratnog oblika i stanjene. Amplifikovani su fragmenti očekivanih dužina za internal transcribed spacer (ITS1/ITS4), kalmodulin (CAL-228F/CAL2Rd) i histon (CYLH3F/CYLH3R) genima i dobijene sekvence su pokazale 100% identitet sa sekvencama C. apii u bazi gena.