To preface, I dont think this is a pest or nutrient problem, because i used the same soil on other plants and it has been affecting them the same. There was also a time where i did not water properly for a month or so. I also live in a subtropical environment.
The wilting starts along the stem bottom up, and the leaves start to yellow, then become brown and drop/hang on the stem ( refer to the pictures ive linked). The wilting has persisted despite watering properly now, no over or under watering. Closest match of symptoms ive got online is some sort of fungal disease, called fusarium or verticillium wilt.
So here comes my questions
1. what is the problem with the plant? Is it fungal?
2. how do i stop the wilting from infecting other plants?
3. Is there a way to stop the wilting in my sweet potato plant?
4. Should I fertilise to strengthen the plant? Is applying some
compost going to work? (I heard that the sheer amount of beneficial microbes will overpower the ones that are destructive to the plant)
Thanks!