Detailed Guide to Controlling Sooty Mold Disease in Loquat
Loquat gray leaf spot mainly damages leaves and also damages fruit, and is a major disease of loquat. When leaves are affected, the initial lesions appear as pale yellow round spots, which then rapidly expand and merge into irregular large lesions with a distinct black ring at the edges. When fruit is affected, round, purplish-brown lesions form, soon become sunken, and later on the lesions grow...
Loquat sooty mold disease is induced by the secretions of aphids, scale insects, whiteflies, and the like,Symptoms:
On the surface of leaves, fruit, and young shoots, a dark brown mold layer that does not invade the host tissue. When it first appears, there are only small mold spots. Later they expand and form a downy growth. It affects leaf photosynthesis and fruit coloring, weakening the tree's vigor.
Control methods:
(1) Spray rosin soda: use a 10-fold dilution in winter and spring; use a 14-16 fold dilution in summer and autumn; or a 50-fold dilution of diesel oil emulsion. It kills pests such as scale insects and whiteflies, and also kills sooty mold fungi.
(2) At the early stage of the disease, spray 0.3-0.5% lime excess Bordeaux mixture.
(4) Do a good job of pruning and training to make the canopy well ventilated and let light through, reducing the incidence of the disease.