Abstract:

【Objective】In this study, pathogenic agents associated with tomato yellow leaf curl disease in Panzhihua, Sichuan Province in China were identified. 【Method】 Diseased tomato plants exhabiting typical stunting, yellowing and leaf-curling symptoms were collected in Panzhihua, Sichuan Province. Using PCR, cloning, and sequencing techniques a begomovirus disease complex associated with tomato was identified for phylogenetic analysis. 【Result】 500 bp fragments were amplified from four samples (SC64-67) using the begomovirus degenerate primer pair PA/PB. The complete nucleotide sequence of isolate SC65 was determined to be 2 732 nts and shared the highest sequence identity (96.0%) with an isolate of Tomato yellow leaf curl China virus (TYLCCNV-Bean-YM) isolated from kidney bean in Yuanmou, Yunnan Province. All tomato samples were found to be associated with the satellite DNAβ molecules. The satellite DNAβ molecule associated with SC65 (SC65 DNAβ) consisted of 1 338 nts and shared 77.5% nucleotide sequence identity with DNAβ associated with TYLCCNV-Y25 isolated from tomato plants in Chuxiong, Yunnan Province. 【Conclusion】 These results suggested that tomato yellow leaf curl disease in Sichuan Province is associated with the TYLCCNV/DNAβ disease complex which may originate from DNA-A and DNAβ molecules of different TYLCCNV isolates.

Key words: tomato (Lycopersicon esculintum Mill.), Sichuan Province, tomato yellow leaf curl disease, Tomato yellow leaf curl China virus, satellite DNAβ