Green bell disease and its control methods

Common diseases of green bell: cottony scale

The female adult is oval or oblong, orange-red or dark red. The body surface is covered with short black hairs, the back is covered with white wax powder and is raised upward, with the highest rise in the middle of the back, while the ventral surface is flat.

Symptoms of cottony scale

They often gather on leaf buds, young shoots and new shoots to cause damage. In severe cases, the leaves turn yellow and the branches wither, resulting in the death of the entire branch or plant. Even if some branches and leaves remain, they will become gray and black due to sooty mold caused by their excrement, seriously affecting their ornamental value.

Methods for controlling cottony scale

Manual control: Check at any time, pinch off the female insects and egg sacs by hand or with tweezers, or cut off the insect branches and leaves.

Drug control: During the migration period of newly hatched nymphs, spray 1000 times diluted 40% oxydemeton-methyl, 1000 times diluted 50% fenitrothion, or 400-600 times diluted ordinary laundry detergent, once every 2 weeks or so, and spray 3-4 times in a row.

Common diseases of green bell: sooty disease

Sooty mold, also known as coal pollution disease, is one of the common diseases of plants. It mainly harms leaves and petioles, and in severe cases also harms the trunk. When the disease occurs, dark brown mildew spots first appear on the surface of the leaves, and then gradually expand, so that the entire leaf or most of the leaf surface is covered with black soot-like substances.

Leaves that are completely covered by soot turn yellow because photosynthesis is affected, eventually causing the entire plant to wither and die.

Symptoms of soot disease

It mostly occurs on the surface of the leaves of Green Bell, appearing as small brown, gray, and black mold spots. Sooty disease often occurs in the hot and humid summer.

Methods for preventing and controlling soot disease

Artificial prevention and control: First, control water and ventilation, and expose the plants to more sunlight instead of through glass to help control the disease. Wipe the infected leaves with light soapy water, then wipe them again with clean water and wipe them dry.

Chemical control: Spraying carbendazim is not very effective. Using thiophanate-methyl for treatment is much better than carbendazim. Thiophanate-methyl can also be used. If there is a lot of soot on the blades, just break them off. Remember to wait until the wounds of broken leaves heal before spraying the medicine.

Common diseases of green bell: stem rot

Stem rot is a serious disease that attacks the basal branches of raspberries. It usually occurs on new shoots, and a dark gray, burn-like spot first appears on the sunny side of the shoot close to the ground.

Symptoms of stem rot

It mainly harms the base of the stem or the underground main lateral roots. The diseased part is dark brown at first, and then spreads around the base of the stem, causing the cortex to rot, the above-ground leaves to turn yellow and wilt, and the whole plant to die in the later stage. Dark brown sclerotia of varying sizes are often formed on the surface of the diseased part.

Stem rot control methods

Manual prevention and control: Check the quality of the potting soil and cut off and burn diseased branches in time.

Chemical control: Spray pesticides from March to August. In mid-May and early July of the disease outbreak, spray 1000 times diluted 38% cypermethrin, 800 times diluted 30% carbendazim/carbendazim, or 500 times diluted thiram on susceptible varieties.