Generally, plants affected by the tomato ( yellow leaf curl virus Tomato yellow leaf curl virus , TYLCV), a Begomovirus strictly dependent on phloem, see their growth slowed down or even blocked (Figures 1 to 4). They take on a puny and bushy appearance, because of the development of numerous axillaries, and the reduction in the length of the internodes. In the case of early infections, they remain dwarf and do not produce fruit.
The shape and / or coloring of the leaflets is altered. Their size is frequently reduced. They gradually curve upwards, giving the limbus the appearance of a spoon (figures 5 to 7). They also show more or less intense interveinal yellowing (Figures 8 and 9). In addition, the blade tends to harden, and sometimes to take on a purplish color, especially at the level of the raised veins under the leaflets.
The flowers drop prematurely; therefore fruit production can be greatly reduced, especially if infections have been very early. The fruits formed are often few and small.
Remember that the proliferation of whiteflies on tomatoes, even without spreading viruses, can cause various symptoms such as leaf spots or fruit coloring abnormalities .