Detection of Cucumber green mottle mosaic virus in low-concentration virus-infected seeds by improved one-step pre-amplification RT-qPCR

Table 2 CGMMV detection by four methods in simulated virus-contaminated seed powder samples with different mass ratios

Infected: healthy seed mass ratio	Mass percentage (%)^b	Method A Ct Value ± SD ^c	Method B Ct Value ± SD	Method C Ct Value ± SD	Method D
1:100	1	14.13 ± 0.04	27.58 ± 0.08	/^f	+ ^d
1:200	0.5	17.05 ± 0.00	29.45 ± 0.01	/	+
1:300	0.333	20.78 ± 0.02	32.78 ± 0.00	/	+
1:400	0.25	23.10 ± 0.04	34.02 ± 0.01	/	+
1:500	0.2	25.13 ± 0.01	35.41 ± 0.02	30.70 ± 0.25	+
1:600	0.167	25.72 ± 0.01	36.01 ± 0.12	33.20 ± 0.21	Undet
1:700	0.143	26.50 ± 0.06	36.57 ± 0.06	36.47 ± 0.31	Undet
1:800	0.125	27.40 ± 0.01	37.37 ± 0.52	36.74 ± 0.12	Undet
1:900	0.111	28.35 ± 0.23	38.64 ± 0.11	37.94 ± 0.40	Undet
1:1000	0.1	29.18 ± 0.98	Undet	Undet	Undet
Healthy	0	Undet^e	Undet	Undet	Undet
Negative	0	Undet	Undet	Undet	Undet

CGMMV Cucumber green mottle mosaic virus
^aThe three methods: (A) one-step pre-amplification RT-qPCR; (B) universal RT-qPCR [14, 24]; (C) Universal RT-qPCR for double-quenchen probes [4]; (D) DAS–ELISA
^bMass percentage of infected seeds in total seeds, %
^cAverage Ct value of two replicates ± SD
^d + , positive
^eUndet., no amplification detected
^fUntested

ISSN: 1746-4811