Fig. 1. Sequence alignment of translation elongation 1-α genes of Colletotrichum spp. used in this study. Green and sky-blue boxed sequences indicate respectively the position of the designed primer cirTef-F and cirTef-R. GJS08_43: C. theobromicola, E183: C. ignotum, 125331: C. circinans, 112.81: C. circinans, 41028: C. caudatum, 40807: C. higginsianum, 42433: C. lindemuthianum, 40893: C. boninense, 40009: C. coccodes, 46159: C. capsici, 40805: C. acutatum, 40003: C. gloeosporioides, 40808: C. orbiculare.
Fig. 2. Sequence alignment of β-tubulin genes of Colletotrichum spp. used in this study. Green and sky-blue boxed sequences indicate respectively the position of the designed primer cirTu-F and cirTu-R. 112.81: C. circinans, 125331: C. circinans, 40981: C. liliacearum, 40009: C. coccodes, 40010: C. coccodes, 40805: C. acutatum, 346.37: C. fructi, 40808: C. orbiculare, 40903: C. orbiculare, 40893: C. boninense, 40013: C. dematium.
Fig. 3. Specificity test of the primer cirTef-F/cirTef-R set against diverse fungal DNAs. M, 1 kb DNA ladder; 1, Colletotrichum circinans CBS 125331; 2, C. circinans CBS 221.81; 3-6, C. acutatum KACC 40805, 43124, 44886, 44887; 7, C. boninense KACC 40893; 8, C. capsica KACC 46159; 9, C. caudatum KACC 41028; 10, 11, C. coccodes KACC 40227, 40808; 12, C. dematium KACC 40013; 13-16, C. gloeosporioides KACC 40003, 40448, 40690, 40892; 17, C. higginsianum KACC 40807; 18, C. liliacearum KACC 40947; 19, C. lindemuthianum KACC 42433; 20, C. musae KACC 40947; 21, C. orbiculare KACC 40808; 22, C. orbiculare KACC 40903; 23, DNA mixture of C. circinans CBS 221.81 and common six molds (Alternaria sp., Aspergillus sp., Cladosporium sp., Fusarium sp., Penicillium sp., Trichoderma sp.); 24, DNA mixture of common six molds.
Fig. 4. Specificity test of the primer cirTu-F/cirTu-R set against DNAs of common six molds. M1, 1 kb DNA ladder; 1, Colletotrichum circinans CBS 125331; 2, C. circinans CBS 221.81; 3-6, C. acutatum KACC 40805, 43124, 44886, 44887; 7, C. boninense KACC 40893; 8, C. capsica KACC 46159; 9, C. caudatum KACC 41028; 10, 11, C. coccodes KACC 40227, 40808; 12, C. dematium KACC 40013; 13-16, C. gloeosporioides KACC 40003, 40448, 40690, 40892; 17, C. higginsianum KACC 40807; 18, C. liliacearum KACC 40947; 19, C. lindemuthianum KACC 42433; 20, C. musae KACC 40947; 21, C. orbiculare KACC 40808; 22, C. orbiculare KACC 40903; 23, DNA mixture of C. circinans CBS 221.81 and common six molds (Alternaria sp., Aspergillus sp., Cladosporium sp., Fusarium sp., Penicillium sp., Trichoderma sp.); 24, DNA mixture of common six molds; M2, 100 bp DNA ladder.
Fig. 5. Conventional PCR amplification of different amounts of Colletotrichum cirninans DNA with the primers cirTef-F/ cirTef-R (A) and cirTu-F/cirTu-R (B). M, 1 kb ladder marker; 1, 10 ng; 2, 1 ng; 3, 100 pg; 4, 10 pg; 5, 1 pg; 6, 100 fg; 7, 10 fg; 8, 1 fg.
Fig. 6. Real-time PCR amplification of Colletotrichum circinans DNA with the primers cirTef-F/cirTef-R (A) and cirTu-F/cirTu-R (B). a, Amplification plot; b, Melting peak analysis; c, Standard curve .Sample 1, 10 ng; Sample 2, 1 ng; Sample 3, 100 pg; Sample 4,0 1 pg.
Fig. 7. Detection of Colletotrichum circinans by conventional PCR using the primer set cirTef-F/cirTef-R in DNA from infected seeds. M, 1 kb ladder marker; 1, Infected onion seed; 2, Control onion seed.
Fig. 8. Detection of Colletotrichum circinans by real-time PCR using the primer set cirTef-F/cirTef-R in DNA from infected onion seeds. A, Amplification plot; B, Melting peak analysis; C, Gel electrophoersis; M, 1 kb ladder marke.r
Table 1. Colletotrichum strains used in this study.
Table 2. Primers designed in this study
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