The nucleotide homology of SZ T1and SZT2 reached respectively 98.9% (3/272) and 96.7% (9/272) as against TTV-N22 of Japan,and the homology of SZT3 and SZT4 reached 67.3% (89/272) and 86.0% (38/272).

• 两者有非常显著性差异(P<0.；01)。 与日本首例TTV-N22株相比；SZT1和SZT2株基因序列同源性为98