Beans farming for beginners
Introduction
Bean, scientifically known as Phaseolus vulgaris L., is a member of the Fabaceae family, which is commonly referred to as the legume family. This family encompasses various types of beans, such as bush beans, common beans, dry beans, dwarf beans, field beans, French beans, garden beans, green beans, haricot beans, kidney beans, pole beans, snap beans, or string beans. Beans are categorized as a warm-season crop and are particularly sensitive to extreme temperatures. Plant growth is hindered by low temperatures, whereas high temperatures expedite it. For optimal growth, most bean varieties necessitate a frost-free growing season that spans from 85 to 120 days.
Growing requirements
The common bean thrives within a temperature range of 15 to 27°C and can tolerate temperatures as high as 29.5°C. However, when exposed to high temperatures nearing or exceeding 35°C, as well as moisture stress during the crucial stages of flower and pod formation, a significant number of blossoms and developing pods are prone to abortion. Optimal growing conditions for common beans entail receiving a rainfall of approximately 350-500 mm throughout the growing season, alongside low relative humidity. This combination helps minimize the risk of bacterial and fungal diseases.
Soil type
Typically, beans necessitate deep and fertile soil that ranges from loose to slightly compact, possessing favorable physical characteristics. The ideal soil pH for beans falls within the range of 5.5 to 6.5. Additionally, it is preferable for the topography of the planting area to be flat or gently rolling, enabling good drainage.
Land preparation
Prior to planting, it is advisable to perform a semi-deep tilling of the soil at a depth of 25 to 30 cm, incorporating manure into the soil during this process. If the soil requires disinfection, another tilling should be carried out, but at a shallower depth, once the necessary time has passed. Following this, basal dressing is applied, and two skim ploughing actions are performed at a depth of 15 cm using either a harrow or a field cultivator. In the case of surface irrigation, appropriate ditches and ridges should be created.
For crops grown in sandy soil, after clearing the previous harvest, the surface of the sandy ground should be leveled. Subsequently, basal dressing is applied.
Planting & Disease Management
Fertilization
The common bean exhibits positive responses to both chemical and organic fertilizers. To assess the fertility status of the soil, it is recommended to conduct a soil test. At the time of sowing, apply fertilizer at a rate of 50 kg per acre, ensuring even distribution. Additionally, for enhanced and uniform growth, as well as to mitigate soil acidity and improve water retention capacity, mix 1 kg of humipower per 50 kg of fertilizer.
Weed management
To maintain a weed-free environment, it is essential to utilize Catapult® 480SL 480SL to effectively eliminate all unwanted weeds. The crucial period for weed control is typically between 15 to 30 days after the seedlings have emerged. For optimal results, it is recommended to employ the recommended herbicide, Bentagran®Top 240EC, at a rate of 50 ml per 20 liters of water. However, it is advisable to minimize or refrain from weeding after the plants have started flowering, as excessive weeding during this stage may lead to a loss of flowers. In summary, the solution involves using Bentagran®Top 240EC at a rate of 50 ml per 20 liters of water.
Irrigation
In rainfed conditions, it is crucial to consider providing supplementary irrigation during drought periods. If a sprinkler system is utilized, it is important to avoid excessive watering during the flowering stage to minimize the loss of flowers. When implementing flood irrigation, it is recommended to use furrows and water the crops once a week for a duration of 2 hours, increasing the frequency during the flowering period.
Disease Management
Bean rust (Uromyces fabae)
The disease is characterized by the presence of numerous reddish-brown pustules on the leaves. It poses a more significant threat to spring beans, and all varieties are susceptible to it. The most substantial damage occurs when the infection takes hold during the flowering and pod-setting stages. To potentially enhance yield in both winter and spring beans, fungicides such as tebuconazole, cyproconazole, azoxystrobin, metconazole, and boscalid + pyraclostrobin can be employed. However, it is unlikely to be beneficial to treat the crop if the infection occurs after pod fill is complete and the crop is entering the senescence phase.
As a solution, it is recommended to spray the affected plants with Absolute® 375SC at a rate of 10 ml per 20 liters of water, combined with Integra® at a rate of 3 ml per 20 liters of water.
Damping-off Rhizoctonia solani
The pathogens responsible for this disease can attack the crop at any stage, starting from seed rot, damping off of seedlings, or causing stunting, yellowing, and eventual death of mature plants. One of the visible symptoms is the emergence of elongated sunken reddish-brown lesions on the roots and stems, typically at or below the soil line. These lesions can constrict the stem, leading to the death of the plant. In some cases, older plants may not exhibit noticeable signs of the disease, although it can still result in reduced yields. If the fungus invades the plant’s pith, it may cause it to turn a brick-red color.
To address this issue, it is recommended to use Trinity Gold® 452WP at a rate of 40 g per 20 liters of water as a solution.
Alternaria leaf spot Alternaria alternata
The presence of small, irregular brown lesions on the leaves is observed, which gradually expand and change color to gray-brown or dark brown. These lesions exhibit concentric zones, and as they mature, older sections may dry out and detach from the leaves, causing a shot hole appearance. Eventually, the lesions merge together, forming larger necrotic patches.
To address this issue, it is recommended to spray the affected plants with Absolute® 375SC at a rate of 10 ml per 20 liters of water.
In the case of Anthracnose caused by Colletotrichum lindemuthianum (Glomerella lindemuthiana), the symptoms differ. Dark brown to black lesions are observed on the cotyledons, while the stems display oval or eye-shaped lesions that become sunken and turn brown with purple to red margins. These cankers weaken the stems, which may eventually break. Pods in the affected areas dry out and shrink, and reddish-brown spots appear on them, which later develop into circular, sunken lesions with a rust-colored margin.
For the management of Anthracnose caused by Colletotrichum lindemuthianum, it is advised to spray the plants with a combination of Absolute® 375SC at a rate of 10 ml per 20 liters of water and Integra® at a rate of 3 ml per 20 liters of water.
Halo blight Pseudomonas savastanoi pv. phaseolicola
The underside of the leaves displays small water-soaked spots that later become necrotic and become visible on the upper surface as well. Around these spots, there may be an area of chlorotic tissue. On expanding leaves, the presence of lesions can lead to leaf distortion. Additionally, red-brown lesions may be visible on the pods, and these lesions may exhibit oozing or eventually turn tan in color.
To address this issue, it is recommended to spray the affected plants with Trinity Gold at a rate of 40 g per 20 liters of water, combined with Integra® at a rate of 3 ml per 20 liters of water.
Pests Management
Aphids Aphis craccivora
There are small, soft-bodied insects observed on the underside of leaves and/or stems of the plant. These insects are typically green or yellow, although their coloration can vary depending on the species and the host plant. In some cases, they may appear pink, brown, red, or black. When the infestation of aphids is severe, it can lead to yellowing and distortion of leaves, the formation of necrotic spots on leaves, and the stunting of shoots. Aphids also secrete a sugary substance called honeydew, which is sticky and promotes the growth of sooty mold on the plants.
To tackle this issue, it is recommended to spray the affected plants with Lexus® 247SC at a rate of 8 ml per 20 liters of water, in combination with Integra® at a rate of 3 ml per 20 liters of water.
Cutworms Agrotis spp.
The stems of young transplants or seedlings are susceptible to being cut off at the soil line. In cases where the infection occurs at a later stage, irregular holes can be seen on the surface of fruits. The larvae responsible for this damage are typically active during the night and hide during the day, either in the soil around the base of the plants or in plant debris from toppled plants. The larvae can exhibit various patterns and colors, but when disturbed, they usually curl up into a C-shape.
To address this issue, it is recommended to drench the affected area with Pentagon® 50EC at a rate of 20 ml per 20 liters of water. It is important to ensure that the soil is moist before applying the solution. For optimal results, it is advised to spray in the late evening or early morning.
Spider mites Tetranychus urticae
Symptoms:
The leaves display a stippled appearance, characterized by yellow dots or spots. In some cases, the leaves may appear bronzed. Webbing can be observed, covering the leaves affected by mites. The mites themselves may be visible as tiny moving dots on the webs or underside of leaves, which can be best observed using a hand lens. Usually, these symptoms are not noticeable until there are visible signs of damage on the plant. As the infestation progresses, the affected leaves may turn yellow and eventually drop from the plant.
Solution:
To address this issue, it is recommended to spray the affected plants with Alonze® 50EC at a rate of 5 ml per 20 liters of water, in combination with Integra® at a rate of 3 ml per 20 liters of water. Applying the solution as a spray can help control the mite infestation and mitigate the damage caused.
Root-Knot nematode (Melaidogyne incognita,M.javanica
These pests have detrimental effects on plants, causing stunting and yellowing. In hot weather, the affected plants may show a tendency to wilt. If plants infested with these pests are carefully pulled out from the soil, their roots will appear distorted, swollen, and bear knots of various sizes. In severe infestations, the roots may decay.
It is important to note that these knots should not be confused with legume nodules, which are typically small, round, and attached to the outside of the roots. In contrast, the swellings caused by root-knot nematodes are found within the body of the root. When active nodules are sliced, they exhibit a pinkish color.
To address this issue, during planting or top dressing, it is recommended to mix 2 kg of Adventure with fertilizer. Another solution is to drench the affected plants with Alonze® 50EC at a rate of 10 ml per 20 liters of water. Implementing these measures can help control the nematode infestation and reduce its negative impact on the plants.
Bean fly (Ophiomyia spp)
The adult bean fly is a small fly, measuring about 2mm in length, and it has a shiny black-bluish coloration. The female fly pierces the young leaves to lay eggs and feeds on the sap that exudes. This feeding activity leads to the formation of yellow blotches on the leaves, which serve as the initial signs of a bean fly attack. These yellow blotches can be useful for monitoring the presence of this pest in the field. The fly’s maggots then tunnel from the leaves down to the base of the stem, where they complete their development.
The feeding activity of the maggots destroys the plant tissue, causing the stem to swell and split, and it also hampers the formation of lateral roots. Compensatory adventitious roots may be produced by the affected plants. The maggots, which are yellow in color, and the pupae, which are brown or black, are often visible through the splits in the stem. Young seedlings and stressed plants may wilt and die when attacked by bean flies. Older or healthier plants may tolerate the attack, but their growth will be stunted and their yield reduced. The damage caused by bean flies is particularly severe in plants growing under unfavorable conditions, such as infertile soils and drought.
To address this issue, it is recommended to drench the affected plants with Kingcode Elite® 50EC at a rate of 10 ml per 20 liters of water. This solution can help control the infestation and mitigate the negative impact of bean flies on the plants.
