Situation of the whiteflies Bemisia tabaci and Trialeurodes vaporariorum in protected tomato crops in Algarve (Portugal)*

Abstract

Protected tomato is the most important horticultural crop in the Algarve (south of Portugal). However, the growing area has decreased by almost 48% since 1995, mainly as a result of the pests Bemisia tabaci and Trialeurodes vaporariorum and the epidemics of Tomato yellow leaf curl virus (TYLCV), a Begomovirus transmitted by B. tabaci. Both whiteflies are vectors of economically important viruses. Recently, Tomato chlorosis virus (ToCV), a member of the genus Crinivirus, transmitted by both B. tabaci and T. vaporariorum, was reported infecting tomato crops in Algarve. A study was carried out to evaluate the dynamics of whitefly populations on tomato crops in Algarve. Population counts of B. tabaci were high in the first months of autumn, then decreased until January, when numbers of T. vaporariorum became higher. Counts of B. tabaci then increased again.

Genetic variation of the greenhouse whitefly,Trialeurodes vaporariorum(Hemiptera: Aleyrodidae), among populations from Serbia and neighbouring countries, as inferred fromCOIsequence variability

“…Trialeurodes vaporariorum is also known to disperse Polyphagotarsonemus latus mites (Palevsky et al , 2001; Petanovic et al , 2010; Marcic et al , 2011) and to vector several bacterial species, such as Xanthomonas pelargonii Brown (O'Reilly, 1974; Peric, 1999). Large infestations of this pest can result in stunted plants and leaf necrosis, lower yields and poor fruit quality (Wisler et al , 1998 a , b ; Albajes et al , 1999; Martin et al , 2000; Lopes, 2002; Ramos et al , 2002; Jones, 2003; Valverde et al , 2004; Fortes et al , 2012; Karatolos et al , 2012). Trialeurodes vaporariorum is polyphagous, and its hosts are plant species that belong to 82 families (Mound & Halsey, 1978).…”

Asymmetric consequences of host plant occupation on the competition between the whiteflies Bemisia tabaci cryptic species MEAM1 and Trialeurodes vaporariorum (Hemiptera: Aleyrodidae)

“…The outcome of interspecific competition between whiteflies is influenced by the host plant and by the temperature and season . B. tabaci is dominant on poinsettia and T. vaporariorum is superior on green beans .…”

“…Thus, whiteflies can affect each other directly as well as indirectly when they coexist. Tomato is a common host of both species – the two whiteflies can feed simultaneously on the same leaf . However, they cannot coexist for more than four generations under controlled greenhouse conditions .…”

“…However, they cannot coexist for more than four generations under controlled greenhouse conditions . In protected tomato crops, populations of B. tabaci are high in the first months of autumn, then decrease until January when numbers of T. vaporariorum become higher . Field surveys in Shandong, China, found both B. tabaci MEAM1 and T. vaporariorum cofeeding on cotton, eggplant, cucumber and poinsettia in September.…”

Transcriptome analysis and comparison reveal divergence between the Mediterranean and the greenhouse whiteflies

“…In some regions, MEAM1/MED and TV coexist and show interspecific competition [ 13 , 14 ]. In these regions of co-existence, they often show apparently different patterns of seasonal abundance: MEAM1/MED become predominant in seasons of relatively high temperatures, while TV becomes predominant in seasons of relatively low temperatures [ 15 ]. While all the three species of whiteflies are polyphagous, MEAM1 and MED have a wider range of host plants than TV [ 3 , 4 ].…”