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Hello friends of the farm today I am going to talk about the pests, diseases and weeds that attack these diminish the quality and health in bean crops, therefore it is imperative to become familiar with the biotic elements involved in production, to take measures preventive and timely solutions.
It is common to find two types of damage: direct, caused by chewing insects, and indirect, caused by sucking insects, which mainly transmit viral diseases.
The bean is a legume native to Latin America that belongs to the Fabaceae family; Its cultivation is among the first places in the world due to its important nutritional level and the economic value it represents. In addition, it should be noted that thanks to its characteristics "the beans" as they are also known form part of the daily diet of many people, only in Mexico their consumption represents 36 percent of the daily protein intake.
There are several factors that can intervene in the success of the production of this legume, among these are the pests and diseases that, depending on the characteristics of each region can cause various damages and large losses that can be seen reflected in the economy of the producers.
THE MOST COMMON BEE PESTS AND DISEASES, BELOW WE WILL PRESENT YOU
PLAGUE OF THE WHITE FLY
White fly: Bemisia tabac and B. Argentifolii. The importance of the whitefly in the bean crop is due to its ability to transmit the golden mosaic virus. The largest populations of this insect occur during the summer (July, September) and decrease in the winter (beginning in October), for which the sowing dates are decisive to reduce risks of damage by whitefly. It is considered that very early sowings (September) or very late sowings (December) are the most affected. In general, the sowings of the third tenth of October are the most appropriate to reduce the mentioned risks. When applications of insecticides are required, the technological stage in which the crop is located should be considered.
The adults of white fly measure 1.5 millimeters, they are of whiteamarillento; They are found on the underside of the leaves and when disturbed they fly quickly. Oviposit sementando hundreds of eggs on the underside of the leaves; the nymphs are flattened and at birth they stick to the leaves sucking the sap and producing a lot of honeyed excreta where the sooty mold develops which gives the plants a black coloration.
They can be combated by periodic and induced defoliation, or prepare infusions of garlic diluted in water and applied by spray to the plants. This will not only eliminate the fly and its eggs, but it will act as a powerful fungicide against different threats. Another effective and friendly way to the environment is to plant calendula or basil, since these plants are natural repellents for the whitefly.
AS THE CHEMICAL CONTROL
It is difficult and expensive, before applying insecticides should be made a good assessment of pest levels and estimate their potential economic damage. It has been found that the application of soap solutions helps the control of the pest at costs comparatively, but the applications must be made with sprayers that guarantee a good coverage. The soapy solution acts on the light waxy layer that protects the body from the plague and exposes it to the sun, causing its dehydration and death.
CHICHARRITAS
They are one of the most common pests that affect health in bean crops; This insect, green in color and 4mm long, usually inserts its eggs in the tissue of the leaf, between the veins and the stem, causing the plant to grow rickety. Adults are about 3 millimeters long, are elongated, tender green, insert their eggs along the ribs on the underside of the leaves. The nymphs are born a few days and go through 5 instars. They are dirty white and just as adults suck the sap from the leaves, causing them to become wrinkled, so the plant stops growing and decreases the production of green beans and the quality of the grain. Plants attacked by nymphs and adults do not develop normally. The leaves have deformations and curls down, with yellowish edges, there is deformation of the pods, general hoarding of the plant and substantial losses of production. Chemical control would be suggested when five or more leafhoppers are found per leaf.
It can be seen that is infected when it has the tip of the rolled sheets, and turn yellow after the wear of their sap. These insects are agents that transmit many viral diseases between plants, more can be controlled by chemical insecticides, and induction of predators such as green laceworm, which does not affect the harvest but is responsible for keeping it sterilized.
TRIPS:
Caliothrips phaseoli. The eggs are inserted into the tissues of the underside of the leaves; the nymphs scrape and suck the leaves producing scars that together give the leaf an ash-like appearance. Later, the heavily attacked leaves turn coppery and then dry up, which can cause premature defoliation of the plant. This damage can be reflected in a considerable decline in performance. Chemical control is suggested when more than five trips are detected per plant and the lower leaves are observed with an ash-like appearance. Sampling is determinant to make a ringed application instead of a total one.
GREEN CHINCHE:
Nezara viridula. It measures on average 15 millimeters in length, it is dark green a little bright. They can have a row of 3, 5 or 7 clear spots more or less equidistant in the front part of the esculeto, just in the limits with the pronotum. The nymphs of this species are dark in color, with four rows of very well defined white spots on the abdomen.
Each female deposits an average of 242 eggs in 3.2 masses; Adult egg development lasts 47 days and adults live an average of 84 days. For the population evaluation it is recommended to hit the plants towards the middle of the camel and without one or more chinches falling for every 12 inches (30cm) of furrow, the use of insecticides is suggested for its control.
RAT OF CAMP:
Sigmodon sp. This rodent of nocturnal habits, preferably of gregarious wheat, is located in greater amount near drains, channels and roads, mainly when these are enmontados; likewise, it is found in cane and rice plantations, where the conditions favor their cohabitation and proliferation. When bean is grown in lots adjacent to the aforementioned crops, a permanent combat campaign should be scheduled.
CONCHUELA CAFÉ:
Euschistus servus. The adult is brown and measures 10 to 15 millimeters long and is characterized by the bad smell it gives off. The eggs are deposited in mass and are shaped like bearing, are of a crystalline yellow tone and when they hatch they turn into a pinkish tinge. The nymphs go through stages of variable color, such as light brown, black with coffee and green with brown spots. Each female deposits about 60 eggs in groups of 17.6 on average over a period of 107 days. The five nymphal instars require 29 days. Adults feed on flowers and pods in formation and inject toxic substances that cause the fall of flowers, avanación, staining and malformation of the grain. The chemical control at the beginning of the infestation is suggested from the flowering stage.
DIABRÓTICA:
Diabrotica balteata. The adult is about 6 millimeters long, is light green with yellow bands transverse in the elytra. Occasionally it occurs in high infestations, causing damage to beans before flowering. The damage manifests as holes of various sizes. When plants are young they can destroy them completely. In very heavy infestations, it attacks flowers and tender pods. Chemical control is suggested when 2 3 are detected.
DISEASES
Bean production can be affected by diseases, which are manifested when the weather conditions are adverse to the crop, mainly high relative humidity and temperatures above normal and when certain management practices are applied, such as the use of non-suggested varieties. sowing outside the date or inadequate management of irrigation water.
RUST
The rust is a fungus that is evident on the underside of the leaf, as red pustules. This contains brown powder, which is spread by the wind, but spreads the carrier infection to other plants, and not only that can be spread by insects or the simple manual handling of farmers. This fungus proliferates in humid and hot climates, and generates a kind of dryness in planting to the point of killing it. So, to avoid and preserve health in bean crops, it is necessary to impregnate in the plant that has been previously identified with products based on Manoze or Atracol.
MOSAICO DORADO
In the most important viral disease in the region and its intensity depends largely on the populations of whitefly that are in or near the crop. Attack all varieties. To prevent this disease, it is suggested to adjust to the aforementioned sowing period (anticipated plantings are the most affected by the disease), to use tolerant varieties and to suitably control the sucking insects, particularly the whitefly.
COMMON MOSAIC:
The virus is transmitted mechanically and through seed of diseased plants, so it is suggested not to use it in subsequent plantings and pay special attention to the use of certified seed. The transmission of viruses in the field is carried out by some species of aphids, for which it is necessary to have an adequate control of them.
MOSAICO ENANO:
This virus is transmitted by whitefly, although it is less frequent than the golden mosaic. To prevent the presence of this disease it is necessary to manage the population of the vector insect, use the suggested varieties and plant at the proposed time.
BACTERIOSIS:
This disease has been detected when humid and warm conditions occur, with haze and strong precipitation. Seed produced in free batches of these pathogens should be used, it is also suggested to fallow to place infected waste in a lower stratum and rotate with tolerant crops. Do not go with machinery, implements or people for the crop when there is presence of dew, to avoid the spread of the pathogen.
Chemical control can be carried out by applying copper-based compounds and antibiotics.
WHITE RUST
Whetzelinia (sclerotinia) sclerotiorum The disease usually begins during flowering, when there is enough foliage to allow a greater moisture retention around the plant. It is caused by the fungus Sclerotinia sclerotiorum, this pathogen can affect more than 400 kinds of plants and among them the beans, causing significant reductions in production. The symptoms are easily noticeable from the stage of formation of the pods, in the stems and branches the white mold often proliferates that little by little turns the same somewhat grayish and then brown, to later dry it completely. It is identified by the white cotton growth that is covering the surface or the interior of portions of branches, pods and leaves.
The pods, stems and branches wither, causing a reduction in the size of the seed. The pods in contact with the soil become infected rapidly. When there is enough moisture in the atmosphere the lesions in the different parts of the plant are covered with the mass of the white mycelium, characteristic of fungus.
To treat this pest, the crops should be rotated, weeding periodically, in addition to removing and burning the remains of the crop to avoid the propagation of the spores.
MILDIU VELLOSO
Undoubtedly, one of the most common bean diseases in Mexico from 1968 to the present, it is transmitted by the fungus Phytophthora phaseoli, which also affects other plant species.
Precisely for this reason, it is mentioned that its severity has increased significantly, attacking different types of beans. To date, no variety that is resistant to this fungus has been found. The disease that occurs is characterized by attacking tender buds and flowers, twisting the tissue and darkening it and finally covering it with a whitish hair until it is killed.
To treat downy mildew it is advisable to spread fungicides weekly during the night, or in rainy periods since the temperature contributes to the sporulation, likewise the weeding and rotation of crops contributes to appease this affection.
Some of these products have a limited number of applications and must be alternated with other types of less concentrated chemicals, in order to detect contamination in the ingestion of crops, this will also help the pests do not generate resistance and can take advantage of maximum the effectiveness of them.
COMMON BACTERIAL BLOSSOM
Also known as bacterial wilt or bacteriosis, it is a fairly common disease generated by the high level of humidity. The symptoms can be seen as wet spots on the leaf. The affected regions tend to be flaccid, surrounded by a yellow zone that grows gradually and turns brown due to necrosis, this infection can reach the seed, wrinkling it and rotting it
To prevent this bean disease, bacteria-free seed should be used and crop rotations should be used as a control measure. Ensure that plants are in proper contact with sunlight and avoid water stagnation in the cultivated soil.
Also use products endorsed by local agricultural regulations, monitor the soil every 15 days to monitor the growth process of crops and promote optimal development of the crop for welfare.
UNDERGROWTH
Although not a disease, it is important to keep bean crops free of weeds.
In the first 30 days after the germination of the crop, this must be kept free of weeds, since otherwise this could reduce production by 50%, weeding is usually applied 2 or 3 times during the planting period of the beans, the second recommended between 60 or 70 days, and the third after 90 days.
Such processes can be carried out manually or by using chemical products in regions of abundant rains and lacking manpower; or the corresponding machinery to perform such large-scale work.
CONCLUSION
The success in the handling of pests depends on the opportunity and sequence in which the different control measures can be used. If we have a good start in the integrated management of pests is to adjust to the dates of sowing suggested and keep free of weeds to the crop, edges and channels, to eliminate diseases is also important to monitor the main pests of the crop, in order to determine the time to perform the control actions. The use of insecticides should be integrated into these measures, respecting the time of application, dose, days to harvest and recording the use of the product in the crop.
SOURCE:
http://sistemaagricola.com.mx/blog/principales-plagas-y-enfermedades-en-cultivos-de-frijol-prevencion-y-combate/
http://www.inforural.com.mx/frijol-plagas-y-enfermedades/
I hope that my article has been useful.
