Biological and molecular characterization of a geminivirus affecting pepper plants in Egypt

Pepper (Capsicum annuum L.) is one of the most economically important crops in Egypt. 
Viruses form a major threat to pepper yield in Egypt causing severe economic losses. Plants 
exhibiting virus-like symptoms (VLS) were collected from the field and subjected to ELISA tests 
using three different antiserums, namely C4 antiserum specific for tomato yellow leaf curl virus 
(TYLCV), TYLCV polyclonal antiserum common for any whitefly transmitting geminiviruses 
(WTGs) and Faba Bean Necrotic Yellows Nanovirus (FBNYV). Plants were also tested by PCR with 
WTGs specific primers. Positive results suggested that the pepper plants were infected with a virus 
belong to WTGs viruses. Experiments proved that the virus could be transmitted by viruliferous 
whiteflies, mechanically and by grafting. Inoculated pepper plants with viruliferous whiteflies 
exhibit curling, downward cup shape, deformation of leaves and stunting of infected plants. PCR 
was also carried out for the inoculated plants using primers specific to TYLCV coat protein gene 
and a negative amplification obtained, indicating that the virus under this study is not the 
previously characterized TYLCV isolate. Host range experiments were carried out to determine 
possible hosts of the virus; tomato, tobacco, cotton, faba bean and zucchini plants. Symptoms were 
recorded and results were confirmed by PCR. The virus was further characterized by studying 
nucleotide sequences isolated from the virus genome sequence by amplification fragments from V1 
and V2 sequences. Viral sequence was blasted to the GeneBank database sequences and the most 
homologue sequences were used to build the phylogenetic tree which showed that the sequence is 
very near at the molecular level to TYLCV isolates which suggest that it could be derived from these 
isolates. The isolated virus was given the name pepper leaf curl geminivirus (PeLCV).