What kind of medicine does rose black spot use?

Rose black spot, also known as brown spot, is a worldwide rose disease. First of all, we should start with the source of infection, and it is best to start spraying when the new leaves stretch in summer. So what kind of medicine does rose black spot use?

What kind of medicine does rose black spot use?

1. First of all, we should start with the source of infection, clean up the fallen leaves and remove the diseased leaves in time. In winter, it is necessary to strengthen the pruning of seriously diseased plants and remove the overwintering pathogens on diseased branches and leaves.

2, the potted plant arrangement should not be too dense, directly on the ground is easy to make the basin soil too wet because of the stagnant water on the ground, it is best to put it on the top of the stepped planting platform. It is necessary to change the watering method and time, slowly watering along the edge of the basin instead of spraying frequently. Do not water at night, because the wet leaves will be conducive to the invasion of bacteria.

3. Medication should be sprayed from the beginning of the new leaves in summer, usually every 7-10 days. The medicament can choose 500 times liquid (75%) of chlorothalonil wettable powder or 500 times liquid (50%) of carbendazim wettable powder, or 500 times liquid (80%) of Dysen zinc wettable powder or 100 times of Bordeaux solution (1) or 1000 times of methyl tropine (70%).

Second, the symptom of black spot of rose

The twigs, pedicels and leaves of rose are all likely to be infected. Purplish brown or brown dots are the initial form of the disease spot, and then expand to 1. 5%. Dark brown or black round spots about 5-3 mm in diameter, some with ciliated edges and some with smooth and neat edges.

The plaque is often surrounded by a yellow halo. The disease spots are usually connected together, and the diseased leaves will appear yellowing in a large area, making the disease spot look like an "island" with a green edge.

Diseased leaves are easy to fall, but there are also a few rose varieties that will not fall. Young branches and pedicels will appear purple or black striped spots, slightly sunken. When the disease is serious, it will cause the middle and lower leaves of the whole plant to fall off, leaving only a few new leaves at the top.

Rose black spot is very serious, but as long as the prevention and control work is done, the impact is still relatively small. Friends who plant roses must take care of them so as not to be contaminated with black spots.