Help with disease identification

[recruiterg]

This is one of my dwarf plants from the dwarf project. The variety is called Mallee Rose. I noticed the lower half of the plant had some yellowing of the foliage after I was gone for a long weekend. The plant didn't get watered that weekend and the temps were hot. Is this some type of disease or simply a response to lack of watering?

[b54red]

Looks like the beginnings of fusarium wilt; but since you are so far north I wouldn't think it would be a problem for you.