Leaf drop as possible Defense mechanisme

[Jordy]

My growing season is almost ending, its also the time of fungi outbreak. In the Green House they pressure is above normal with grey mold as the most common one.
The normal tomatoes keep their leafs for a very long time even when its attacked by grey mold to their own demise.
My f3 line holds its the own with great resistance in its leafs/stem/truss and fruit.

Even if grey mould enters the leaf by insect damage,and about 3 small leafs get infected, it aborts the whole leaf by turning yellow.

I compared 24 normal vs 14 f3 plants in the same plot in the greenhouse.

Im interested by what causes this mechanism.