Final diagnosis


Jaunisses d'été et d'hiver des salades

When infections are very early, yellowing between the veins may be observed on young plants. Two low leaves show such a symptom on this lettuce plant. The earlier the attacks, the more the jaundice will affect yields. <b> Beet western yellows virus </b> (<i> Beet western yellows virus </i>, BWYV) and <b> beet pseudo-yellows virus </b> (<i > Beet pseudo-yellows virus </i>, BPYV)
Yellows can appear after planting; this is the case with this lettuce which has reached the 15 leaf stage. Regardless of the stage of development of the plants, yellowing is always revealed on the lower leaves. <b> Beet western yellows virus </b> (<i> Beet western yellows virus </i>, BWYV) and <b> beet pseudo-yellows virus </b> (<i > Beet pseudo-yellows virus </i>, BPYV)
Once infected, the number of affected leaves will increase as the lettuce develops. Yellow spots appear between the veins at first. Subsequently, we can speak of interveinal chlorosis. <b> Beet western yellows virus </b> (<i> Beet western yellows virus </i>, BWYV) and <b> beet pseudo-yellows virus </b> (<i > Beet pseudo-yellows virus </i>, BPYV)
Thus, a high proportion of leaves turn yellow. The yellowing has spread over the leaf blade and spread to a large number of leaves. <b> Beet western yellows virus </b> (<i> Beet western yellows virus </i>, BWYV) and <b> beet pseudo-yellows virus </b> (<i > Beet pseudo-yellows virus </i>, BPYV)
The blade of this low leaf shows a peripheral yellowing of the blade which becomes progressively general. The veins remain green. <b> Beet pseudo-yellows virus </b> (<i> Beet pseudo-yellows virus </i>, BPYV)
The chlorotic parts of the leaf blade sometimes take on a reddish tint. This is the case, for example, in periods of low temperatures. <b> Beet western yellows virus </b> (<i> Beet western yellows virus </i>, BWYV) and <b> beet pseudo-yellows virus </b> (<i > Beet pseudo-yellows virus </i>, BPYV)
On batavia, as on lettuce, the lower leaves turn yellow first. <b> Beet western yellows virus </b> (<i> Beet western yellows virus </i>, BWYV) and <b> beet pseudo-yellows virus </b> (<i > Beet pseudo-yellows virus </i>, BPYV)
There is always yellowing between the veins of the leaf blade, the veins remaining green. <b> Beet western yellows virus </b> (<i> Beet western yellows virus </i>, BWYV) and <b> beet pseudo-yellows virus </b> (<i > Beet pseudo-yellows virus </i>, BPYV)
On romaine, yellowing is also observed between the veins of the leaf blade, the veins remaining green. <b> Beet western yellows virus </b> (<i> Beet western yellows virus </i>, BWYV) and <b> beet pseudo-yellows virus </b> (<i > Beet pseudo-yellows virus </i>, BPYV)
The <b> Beet western yellow virus </b> (<i> Beet western yellow virus </i>, BWYV) is a paraspheric polerovirus with an isocahedral structure.
The particles of the <b> beet pseudo-yellows virus </b> (<i> Beet pseudo-yellows virus </i>, BPYV) are flexible and filamentous.