Black Stems on Broad Beans Help !

Can anyone help me out here ?

I noticed this morning that on some of my broad bean plants the stems have gone black, in a bruised sort of appearance.

This has happened in the last couple of days and the plants that are affected look horrible.

Previous to this problem there was also a lot of blackfly, but I had dealt with that by washing with Fairy Liquid solution, and seemed to have got rid of most of them.

I'm guessing I'll have to cut the affected plants out.

Can anyone shed any light on this ?

 

It would appear that the most common disease is chocolate spot fungus. Lawrence Hills (organic) reckons watering with comfrey liquid might help, but reckons needs more compost etc before planting.
Also bean anthracite that Hills thinks can be stopped by bordeaux mixture if the attack is before the beans flower.
Feels disease is more likely if ground is wet.

 

It sounds to me like foot rot. With this the stem base and roots turn dark and the leaves turn yellow. Treatment is by lifting and burning the infected plants and treating the ground with Cheshunt compound. David.