First Report of Colletotrichum acutatum on Tomato and Apple Fruits in the Czech Republic

Abstract

Apple (Malus domestica Borkh.) is a fruit traditionally grown in the Czech Republic, and tomatoes (Solanum lycopersicum Mill.), too, are widely raised in this region. Colletotrichum acutatum J. H. Simmonds is a polyphagous fungal plant pathogen. Earlier, this pathogen caused disease on strawberry in the Czech Republic (2), and now it has become an important pathogen on safflower (4). During the 2010 harvest, anthracnose symptoms were noticed on the fruits of apple and tomato. Infected apples fruits (localities Velká Bíteš and Znojmo) and tomatoes (localities Velká Bíteš and Žabčice) were collected. Typical symptoms on fruit surfaces were round, brown, shriveled and sunken spots, 1.2 to 2.0 cm, with orange conidial masses appearing on the spots. A fungus was isolated from each host on potato dextrose agar and cultured at 25 ± 2°C for 10 days. Mycelium was superficial, partly immersed, and white to gray with occurrence of orange conidial masses. Conidia of the tomato and apple isolates were colorless and fusiform. The size of conidia from the apple and tomato isolates, respectively, ranged from 11 to 15 × 2.5 to 3.5 μm and 11 to 16 × 2.5 to 4 μm. Morphological characteristics suggested that the isolated fungi was a Colletotrichum sp. To fulfill Koch's postulates, healthy tomato and apple fruits were disinfected with 3% sodium hypochlorite for 2 min and rinsed in sterile distilled water. Fruits were pinpricked with a sterile needle and 10 μl of a spore suspension (1 × 105 conidia ml–1) was inoculated by pipetting into the wound. Control fruits were treated with sterile distilled water. The fruits were transferred to a growth cabinet and maintained at a temperature of 25 ± 2°C, relative humidity of 70 ± 5%, and a photoperiod of 12 h. Similar disease symptoms as in the collected fruits were observed on tomato fruits at 7 days and apple fruits at 20 days after inoculation, while no symptoms appeared on control fruits. The pathogen was reisolated from infected fruits. Species determination of the isolates was confirmed by PCR. Specific primers designed in region ITS1, the 5.8S RNA gene, and region ITS2 of the pathogen DNA were selected. Specific primers CaInt2 and ITS4 were used to identify C. acutatum (3), and primers CgInt and ITS4 were used to determine C. gloeosporioides isolate CCM 177 (1), which was used as a control. Our isolates yielded PCR products (490 bp) only with primers designed for C. acutatum. The C. gloeosporioides isolate yielded a PCR product (450 bp) only with CgInt and ITS4 primers. PCR products were sequenced and identified with the BLAST program. The sequence of the tomato fruit isolate (Accession No. JN676199) and apple fruit isolate (Accession No. JN676198) matched with 100% similarity to the C. acutatum sequences in GenBank. The control isolate of C. gloeosporioides matched 100% to sequences AJ749682 and AJ749692. To our knowledge, this is the first report of C. acutatum on tomato and apple fruits in the Czech Republic. This pathogen can endanger the production and storage of apples and tomatoes in this region. References: (1) P. R. Mills et al. FEMS Microbiol. Lett. 98:137, 1992. (2) D. Novotný et al. Plant Dis. 91:1516, 2007. (3) S. Sreenivasaprasad et al. Plant Pathol. 45:650, 1996. (4) J. Víchová et al. Plant Dis. 95:79, 2011.

Sensitivity of Colletotrichum acutatum Isolates to Selected Fungicides

“…This organism infects fruit plants, vegetables, ornamental plants, oil crops, fodder crops, conifers and weeds (Freeman et al, 2001;Mari et al, 2012;Peres et al, 2008;Sreenivasaprasad and Talhinhans, 2005). Incidence of C. acutatum on strawberry, lupin, saffl ower, cherry, tomato, apple trees, and gooseberry has been confi rmed in the Czech Republic (Novotný et al, 2006;Víchová et al, 2011Víchová et al, , 2012Víchová et al, , 2013.…”

Evaluation of safflower varieties for resistance to the fungal pathogen, Colletotrichum acutatum

“…and vegetables (Capsicum annuum L. and Lycopersicon esculentum Mill.) (Sreenivasaprasad & Talhinhas 2005;Víchová et al 2012) as well as ornamental plants and conifers (Guerber et al 2003). Nowadays C. acutatum is considered as a significant pathogen of safflower (Carthamus tinctorius L.) .…”

Interactions of brown marmorated stink bug, Colletotrichum acutatum and trap crops in organic tomato production

“…Understanding possible differences in pathogenicity and lifestyles in species and races of Colletotrichum is necessary to develop and implement disease control strategies (Hyde et al 2009). However, only a few papers on tomato anthracnose confirmed the genetic identity of the organism used (Gutierrez et al 2006;Jelev et al 2008;Vichova et al 2012;and Diao et al 2014). Most earlier studies did not (Dillard 1989;Sanogo et al 2003;Costa et al 2006;Aqeel et al 2008;Minuto et al 2008;Nitzan et al 2008;Ben-Daniel et al 2009).…”

“…In addition to C. coccodes, C. acutatum, C. dematium, and, C. truncatum can cause tomato anthracnose as well (C. truncatum has only been reported as causing tomato anthracnose in China) (Gutierrez et al 2006;Jelev et al 2008;Vichova et al 2012).…”

“…The optimal temperature for growth of a Chinese isolate of C. truncatum in culture is 25-30°C (Diao et al 2014), whereas Dillard's isolate of C. coccodes had an optimal temp of 24-28°C. Optimal cultural growth temperatures have not been documented for C. acuctatum or C. dematium isolates that cause tomato anthracnose (Vichova et al 2012;Jelev et al 2008, Gutierrez et al 2006. However, C. acutatum isolates from tomatoes were successfully cultured at 25°C (Vichova et al 2012;Jelev et al 2008); and both C. dematium and C. acutatum were successfully cultured at 28°C (Gutierrez et al 2006).…”