Diaporthe pseudolongicolla: The new pathogen on soybean seed in Serbia

Abstract

Seed decay is one of the most important diseases of soybean (Glycine max (L.) Merr.) that has a negative impact on the market grade of soybeans. The disease is mainly caused by Diaporthe longicolla, along with other Diaporthe species. Screening of soybean seeds health status in Vojvodina Province, Serbia, showed cultural and morphological variability among isolates identified as D. longicolla. With the use of DNA sequences of internal transcribed spacer (ITS1-5.8S-ITS2) region and partial translation elongation factor 1-alpha (EF1-α), the new species was determined. BLAST analysis showed 100% identity with D. pseudolongicolla (syn. D. novem) that was described in this study and its taxonomic revision is discussed. Pathogenicity trial showed that both species, D. longicolla and D. pseudolongicolla, are highly pathogenic on soybean stem and seed, causing 100% of stem wilting and more than 82% of seed decay.

Trulež semena je jedna od najvažnijih bolesti soje (Glycine max (L.) Merr.), koja negativno utiče na vrednost soje na tržištu. Najčešće je uzrokuje Diaporthe longicolla, zajedno sa drugim Diaporthe vrstama. Pregledom zdravstvenog stanja semena soje u Vojvodini (Srbija) uočena je morfološka varijabilnost između izolata identifikovanih kao D. longicolla. Upotrebom sekvenci DNK iz ITS regiona (ITS1-5.8S-ITS2) i elongacionog faktora 1-alfa (EF1-α) potvrđeno je prisustvo nove vrste na semenu soje. BLAST analizom je dokazana identičnost od 100% sa D. pseudolongicolla (sin. D. novem) koja je opisana u ovom radu i čija taksonomska revizija se razmatra. Ispitivanja patogenosti su pokazala da su obe vrste, D. longicolla i D. pseudolongicolla, visoko patogene na stablu i semenu soje uzrokujući 100% uvenuće biljaka kao i trulež više od 82% semena.