Two common causes of plant diseases

When raising horticultural plants, we often encounter a lot of plant diseases, but many flower lovers often do not know what causes plant diseases. In fact, finding out the cause can also be of great help to the treatment of plant diseases. The editor summarizes the two major causes of plant diseases for you.

Rose (details)

Generally speaking, there are two main causes of plant diseases:

One is caused by unsuitable environmental conditions, which is called physiological diseases, and its causes are mainly climatic conditions and moisture, soil, fertilizer and so on.

The other is caused by biological infection, which is called infectious disease, which is caused by pathogens, susceptible plants, environmental conditions and man-made factors. If the pathogen infects plants, the disease may not occur, and whether the disease can occur depends on the disease resistance of plants. If the disease resistance is strong, the disease will not occur or the disease will be very mild. Therefore, selecting disease-resistant varieties and improving plant disease resistance is one of the main ways to control diseases. With pathogens and host plants, the occurrence of diseases also depends on environmental conditions, so we should actively create environmental conditions suitable for plant growth and development in order to reduce the occurrence of diseases. In order to improve plant resistance and create environmental conditions suitable for plant growth and development, it is necessary to strengthen management by means of horticulture, including soil, fertilizer, water, pruning and so on.

Control of common diseases of pteridophytes

First, anthrax. It mainly harms the young leaves of the plant. The injured site began to show small dark brown spots with waterlogging shape or near circle at the leaf edge or tip, and then gradually expanded from several disease spots to irregular patches, the color became scorched yellow, and some of the disease spots were cloud-like, with a light red halo on the edge. in the later stage, the middle part of the disease spot became gray-white, there were many tiny black spots, and the whole leaf died in severe cases. It spreads rapidly at 25 ℃ and humidity between 80% and 90%.

Prevention and treatment: the disease is mainly prevented, and should be prevented by spraying in the rainy season of new leaves and the season of high temperature and humidity. At the initial stage of the disease, 75% chlorothalonil 500 times solution, or 50% carbendazim wettable powder 800-1000 times solution, or 70% topiramine wettable powder 800-1000 times solution can be sprayed for prevention and treatment.

Second, brown spot. Also known as leaf spot or leaf blight. Often occurs at the top of the leaf, the damaged leaf is a small round black spot at the beginning, then expands into a round or near round, the edge of the disease spot is black-brown, the center is gray-black and there are small black spots, and then the disease spot expands rapidly, and the leaf finally becomes black, withered and dies. The main route of transmission is defoliation, which can occur in spring, summer and autumn, and is easy to be popular in high temperature and humidity season.

Prevention and treatment: the diseased plants should be isolated and sprayed immediately, and the infected branches and leaves should be cut off and burned at the same time. Spray protection can be controlled by 50% carbendazim 1000 times, 50% methyl topiramate 1000 times, and Bordeaux 200 times.

Third, rust. It can occur on species such as Cuiyun grass, and light yellow powder is distributed on the leaf surface in May.

Prevention and control methods: 65% Dyson zinc wettable powder 500 times solution, stone sulfur mixture Baume 0.3 to 0.4 degree solution, spray every 10 to 15 days, continuous spray 3 to 4 times, can achieve certain results.

Introduction to common diseases of Dishui Guanyin

Dishui Guanyin (details) is a common indoor foliage plant, which gets its name because it drips water in a humid environment. Although it is not difficult to cultivate Dishui Guanyin, it can also get sick. In general, the diseases of dripping Guanyin are mainly reflected in leaves, including leaf spot and anthracnose.

Dishui Guanyin (details)

1. Leaf spot disease can be sprayed with chlorothalonil or carbendazim 800 times for 3 consecutive times, every 7 days. Anthracnose needs to be foliar sprayed with 75% methyl topiramate 500 times, once every 7 days, 3 times in a row, basically controllable. Because Guanyin is a foliage plant, once the leaves get sick, it will inevitably affect its ornamental effect, so we should give priority to prevention.

2, reaction on the stem, there is a Fusarium wilt, caused by bacterial infection, this disease is not easy to detect at the beginning, once found, it will be very serious. If it is found that the stem is crooked to one side, or there is wilting, it must have given birth to Fusarium wilt, and the disease can be removed with a knife. The boundary between the disease and the non-disease is very clear, and it can be broken off by hand. If the diseased area is less than 1/3 of the stem, you can apply a layer of chlorothalonil solution to the non-diseased area and keep it dry. Apply it again every 10 days, and you can basically recover after 20 days.