How does aloe grow black spot?

Aloe vera is a perennial evergreen herb of the Liliaceae. It is native to tropical arid regions of Africa and is distributed almost all over the world. Its exudates have been widely used in medicine and daily chemistry. In Chinese folk, it is used as a natural medicine for beauty, hair care and treatment of skin diseases. Let's take a look at the long black spots of Aloe vera.

Symptoms of dark spots in aloe vera

Aloe black spot is a bacterial disease that seriously affects the growth and quality of aloe, which can lead to the failure of aloe planting. Water filamentous plaques appeared on the leaves at the initial stage of the disease, and then developed into nearly round black-brown plaques, with radial edges and yellow or yellow-black halos around them. In the later stage of the disease, there are many dark brown particles on the disease spot, the leaf surface is sunken, and the available mesophyll is completely lost.

The law of black spots in aloe vera

Aloe black spot disease varies according to the resistance of aloe varieties. When the temperature was below 20 ℃ and lasted for two hours, the plant metabolism of most aloe varieties was blocked, and the resistance began to decrease, and local disease spots appeared in the infected leaves. When the temperature was below 15 ℃ for more than two days, the incidence of disease spots accounted for about half of the leaves. When the temperature was below 12 ℃, the leaf incidence reached 2 ℃, and when the temperature dropped to 8 to 10 ℃, the leaves were basically covered with disease spots. Especially in the areas where frost damage occurs in open field cultivation, the incidence rate is higher. In addition, typhoon, foggy weather, hail, Rain Water concentration, day-night temperature difference of more than 10 ℃ can also cause the disease and can lead to the spread of the disease.

How does aloe grow black spot?

The main results are as follows: 1. Select disease-resistant varieties, the most susceptible to disease spot is aloe vera, followed by Yuanjiang aloe, tree aloe, aloe vera, soapy aloe and so on. Therefore, it is best to choose Curacao and Yuanjiang aloe with disease resistance and high utilization rate.

2. The newly introduced seedlings must be disinfected and usually soaked in 1000 times of carbendazim wettable powder for 5 to 10 minutes to dry. The seriously diseased plants should be buried deeply, and the soil in the affected area should be disinfected with 1000 times of carbendazim wettable powder and 70% methyl thiophanate wettable powder.

3. Ensure that the lowest growth temperature of aloe is above 8 ℃ during planting, and reduce and control the source of disease at the same time. Single ridge planting was adopted to improve ventilation and light transmission conditions. Under the premise of applying sufficient base fertilizer, 0.1% potassium dihydrogen phosphate and 0.1% zinc were added to enhance the disease resistance of the plant. At the same time, do a good job of field drainage to prevent stagnant water in the field. During the frost period, the smoking method was adopted to increase the temperature for comprehensive control.

4. Aloe black spot can be treated with 1000 times of 75% methyl thiophanate wettable powder, or 1000 times of 50% carbendazim wettable powder or 70% methyl thiophanate wettable powder.