How to treat aphids on beans, other pests of legumes and control measures
Legumes are generally considered food plants and are widely used in agriculture. Beans - the fruits or seeds of these crops - are valuable food products, some legumes are grown as fodder and even decorative crops. Like any other cultivated vegetation, beans are susceptible to parasites and various diseases. In beans, pests and diseases have long been known, and methods of dealing with them are available and effective.
Bean diseases
Beans, like many crops, are susceptible to disease and pests. Let's list the main ones.
Fusarium
This fungal pathogen most commonly infects peas and soybeans. Sources of the disease are contaminated soil, plant debris and seeds, where protozoa parasites have penetrated. Plants with fusarium disease are easily removed from the soil, as their roots rot. In addition to the roots, the disease affects the leaves and flowers of legumes, the so-called tracheomycotic wilting occurs.
As a result of the action of the fungus, there is a loss of yield up to 50%, deterioration of the quality of fruits and seeds, and loss of seedlings.
Peronosporosis
The disease manifests itself in two forms - diffuse and local. It is clear that during local development, individual parts of the plant, mainly leaves, are exposed to the influence of the fungal parasite. With diffuse spread, the infection even penetrates the seeds, and dark yellow spots appear on the stems, leaves and beans. Getting sick, legumes lag behind in growth, yield decreases and foliage dies.
Powdery mildew
This disease is caused by various forms of powdery mildew, the development is facilitated by dry weather. Affected plants appear to be covered with a whitish bloom containing mycelium, conidia and other parasite source substances.
Rust
The causative agent is a diverse dioecious obligate parasite - the fungus Uromyces pisi B.D. In the spring, it begins to attack the weeds, and already from them the wind transfers the disease to legumes. The disease got its name for the orange-brownish color of the affected areas. Rust appears on beans in the middle of summer. The spores of the fungus spend the winter in the roots of the weed and again in the spring begin to infect the shoots.
Ascochitosis
It is manifested by the presence of dark spots on the stems, leaves and beans of plants. The causative agents are Ascochyta fungi. It develops rapidly during long rainy days. The infection has become widespread in almost all areas of cultivation of peas and other legumes.
Bean pests
Bean pests can reduce yields and alter the taste of crops.
Legumes and pea aphids
This insect is up to 2.7 mm in size, from green to black. They are also called beet aphids. They love to eat peas, vetch, lentils. They live in whole colonies on plants and draw out all the juices from them. This leads to damage to the stems, shedding of flowers and buds, and a decrease in yield. Females lay eggs that are able to survive the winter and turn into hungry insects again in the spring.
Pea weevil
The larvae of this beetle develop in the seeds of legumes. It belongs to the order of Coleoptera and is a half-centimeter-sized beetle with short elytra and spotted color. In the spring, beetles eat the pollen of flowering legumes, after the beginning of budding, the females lay eggs on the pods. From the eggs, harmful larvae appear, which gnaw through the valves and penetrate inside.
Directly in the seeds of the beans, the larvae eat out the insides, forming a cavity. Often, the beetles that emerged from them remain hibernating inside the beans. The material damaged by them has poor germination and is unsuitable for food.
Nodule weevils
A group of bugs with an oblong body and up to 5 mm in size. Winters in the upper layers of the soil on crops of legumes or grass. In the spring, they begin to feed on seedlings of beans, which leads to damage to plants and their weakening. Females leave their eggs in the soil or the lower parts of the plants. The hatched larvae feed on the roots of legumes. Adult beetles appear in the second part of summer and feed on leaves.
Disease and pest control
To protect legumes from disease or to minimize the effects of infections, you must adhere to the following methods:
- observe the rule of crop rotation, that is, alternate planting legumes with other plants (not legumes);
- isolate crops from other perennial beans;
- use varieties that are resistant to diseases;
- destroy weeds and post-harvest residues;
- before sowing, treat the seeds with fungicidal drugs (foundazol, TMTD, maxim, biofungicide phytosporin-M);
- for powdery mildew, spraying is used - with a 1% solution of colloidal sulfur (50 grams per hundred square meters) or ground sulfur (250 grams per one hundred square meters);
- for rust and bacteriosis, spray with a 1% suspension of Bordeaux liquid (in the period before flowering);
- use mineral fertilizers.
The pest control measures are as follows:
- sowing early (reduces the risk of pests);
- insecticide treatment;
- removing plants with symptoms of infection;
- the addition of nitrogen and phosphorus-potassium fertilizers helps to fight insects;
- heat treatment of seeds and fumigation.
With proper care and adherence to all measures for processing the plant, you can get rid of diseases and pests of legumes.