Soft Rot – (unidentified bacterium): Leaves collapse to the ground [see illustration], as a result of decay originating in the crown. There is a water-soaked appearance to the leaves. Although the epidermis remains intact in this area, the tissue underneath is disintegrated. Leaves are easily detached from the crown. The causal agent has not yet been identified, but is presumed to be a bacterium. The disease seems to start in the crown area, where water accumulates. The heating of this water may be a predispositional factor for this disease. The disease is not common. The recommended control is to remove symtomatic plants from the field. Implements used to do this should be chemically disinfested.
Tip Dieback – (physiological – oedema): The initial symptom is a water-soaked appearance at the tips of leaves [see illustration. The tissue remains rigid and the discoloration does not progress to the crown. Several days later, the affected portion dries and shrivels, leaving a string of firm, brown tissue, while the rest of the leaf remains green and succulent. This disorder is uncommon and occurs with certain weather patterns. It was documented early one summer when a period of overcast weather with heavy rain was followed by hot, sunny weather. Plants in waterlogged soil that were exposed to the sun were injured, while those that were shaded were not. There is no remedy for this injury, but leaves can still be processed if the affected portion is removed.
Slime Mold – (non-pathogenic): Small (1-inch diameter), white globular bodies with a black powdery interior are often seen attached to lower portions of leaves. These are fungi known as slime molds and have never been implicated as causal agents of aloe diseases. No control measures are warranted.