Epidemiology of tomato yellow leaf curl begomovirus in the Fayium area, Egypt

Abstract

Tomato yellow leaf curl begomovirus (TYLCV) severely invaded tomato plantations in Egypt (Lower and Middle Egypt) in 1989. This study aimed to discover the relationship between TYLCV and other epidemic-associated factors in the Fayium area. The rate of TYLCV infection was inspected visually for three successive years (1994/1996) in the Fayium area. During the same period, whiteflies were collected for virus detection using bait-plant and DNA hybridization techniques. DAS-ELISA was used to detect mixed virus infections in tomato plants. TYLCV infection was prevalent (60-68%) and severe (2.1-3.0) in the Fayium fields. Cucumber mosaic cucumovirus (CMV) was found in some fields (5-28%) with moderate severity (1.0-20). Potato Y potyvirus (PVY) and potato leaf roll polerovhs (PLRV) were found in few fields (5-19% and 5% respectively) at very low seventy. There was a negative correlation between TYLCV Occurrence and distance from the source of infection, and a positive correlation (98%) between TYLCV intensity and percentage of viruliferous whiteflies in 1994 and 1995. There was no positive correlation between TYLCV and the total population of whiteflies caught during the same period. Five percent of viruliferous whiteflies, as proved by cDNA hybridization, led to 46% TYLCV infection. The same percentage of whiteflies, as shown by bioassay, led to 68% TYLCV infection. Monitoring of viruliferous whiteflies could be used for early prediction of TYLCV infection.

Effect of Different Planting Time on Tomato Yellow Leaf Curl Virus (TYLCV) of Tomato and Its Impact on Yield in Bangladesh

“…For this, the relationship between the whitefly population and incidence of TYLCV was investigated. A positive correlation between the incidence of TYLCV and 46 whitefly population (0.9435227) was recorded which was supported by Saikia and Muniyappa [30], Polizzi et al [31] and Aboul-Ata et al [32]. The present study also revealed the relationship between the whitefly population and yield of tomato.…”

Epidemiological Studies of Tomato Leaf Curl Virus and Whitefly Population and Their Management Using Botanicals

“…In present investigations, whitefly population variedly increased from April to June and these results are supported by the previous studies where whitefly population was recorded maximum in March to June resulting in more incidence of disease (Bonato et al, 2007;Garrett et al, 2006;Rahman et al, 2006;Rashid et al, 2008). Incidence of TLCV was directly proportional to the vector population, B. tabaci (Aboul-Ata et al, 2000). Developmental processes and activities of whitefly are favored by increasing temperature and relative humidity.…”

Studying genetic diversity of whitefly B. tabaci Egyptian isolates in relation to some worldwide isolates

“…Virus transmission by B. tabaci is responsible for yield reduction reaching 68% in tomato as has been observed by Aboul-Ata et al [3], five percent of viruliferous whiteflies led to 46% TYLCV infection. The same percentage of whiteflies led to 68% TYLCV infection tomato field crop in Egypt.…”