Analysis of resistance in tomato and sweet pepper against the greenhouse whitefly using electrically monitored and visually observed probing and feeding behaviour
H. Lei et al., Analysis of resistance in tomato and sweet pepper against the greenhouse whitefly using electrically monitored and visually observed probing and feeding behaviour, ENT EXP APP, 92(3), 1999, pp. 299-309
Different types of plant resistance against the greenhouse whitefly, Triale
urodes vaporariorum, were distinguished according to the tissue location of
the resistance factors. The effects of resistance factors were compared by
measuring the electrically monitored and visually observed probing and fee
ding behaviour of whiteflies on two resistant tomato genotypes (82207 and 8
2216), a susceptible tomato cultivar, and a non-host plant, sweet pepper. O
n sweet pepper, whiteflies displayed very short first probes, very long pat
hway probing and spent much time on non-feeding activities such as walking
and standing still. Also, a high percentage of whiteflies rejected sweet pe
pper without ingesting substances from the phloem vessel. These data sugges
t a strong resistance that is based on the factors present in surface/epide
rmis and/or mesophyll layers of this plant. The behaviour of whiteflies on
tomato 82207 was very different from that on sweet pepper. On tomato 82207
whiteflies apparently did not perceive resistance factors on the leaf surfa
ce and in the mesophyll. Resistance factors appeared to be present in the p
hloem tissue, because a higher number of phloem phases, longer phloem saliv
ation periods and shorter phloem ingestion periods were observed when compa
red with the susceptible tomato cultivar. Tomato 82216 showed no clear resi
stance factor in the phloem. The importance of combined EPG and behavioural
research for host-plant resistance studies are discussed.