Abstract: There exists the compound infection of Tomato chlorosis virus (ToCV) and Tomato yellow leaf curl virus (TYLCV), and the incidence of the two diseases presents a tread of increase in recent years, which becomes a new threat to tomato farming. In order to study the interaction and variation of the two virus genes after single and mixed infection, the molecular identification and sequence analysis of the CP gene and the HSP gene of ToCV and the gene of TYLCV occurred in Tianjin were carried out. The results showed that, compared with the single infection samples, 6 base mutations of TYLCV were found in mixed infection samples, i.e. 73rd A→C, 92nd A→G, 347th C→T, 1 209th C→T, 1 618th A→G and 2 107th A→T, among which the 73rd and 92nd mutations were not in the coding region and the other four were located in the ORF box with 3 missense mutations and one samesense mutation(1 209th). There was also one samesense mutation in the CP gene of ToCV. There were 4 base mutations in HSP gene of ToCV, among which the 826th T→C and 1 166th G→A were samesense mutations, while the 1 395th A→G and 1 630th A→G were missense mutations. The accumulation amount of TYLCV and ToCV in tomato samples after single infection and mixed infection were analyzed by RT-qPCR. The results showed that the accumulations of TYLCV and ToCV had no significant difference between single infection and mixed infection. In the mixed infection samples, the copy of TYLCV was about 262-436 times that of ToCV.

Key words: TYLCV, ToCV, Mixed infection, Sequence analysis, Real-time quantitative PCR

CLC Number: 

• S436.412.1

• Q78