Scientific Name Phaseolus vulgaris L.
Order / Family Fabales: Fabaceae
Local Names Maharagwe (Swahili)
Bush beans, common beans, dry beans, dwarf beans, field beans, French beans (also known as green beans or snap beans), garden beans, haricot beans, kidney beans, pole beans or string beans
Many names are used for Phaseolus vulgaris. These include 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.
However, presently, two distinct bean types are recognised in the region: French beans (green beans) and common beans (dry beans). French beans are the immature green pods of P. vulgaris and are primarily grown for export market to European Union and elite local urban markets. Common beans are the second most important staple food to maize for the local people.
Beans were introduced to Africa from Latin America several centuries ago. To date beans are a vital staple in Africa, providing the main source of protein. Common beans are mainly grown by women for subsistence and for the local market. French beans (green/snap beans) are grown as a cash crop by large scale and smallholder farmers. They are a major export vegetable commodity in Eastern Africa.
Bush bean in flower
Purple snap bean variety
Runner bean flowers
Pole bean plant with pods
Green bean flowers and pods
Black beans are a staple in many Mexican and Brazilian dishes. They have a velvety-smooth texture and mild flavor. They also have a lower glycemic index than many other high-carb foods, helping to reduce the spike in blood sugar that occurs after eating a meal.
2. Black-Eyed Peas
This Southern staple has a beige hue with an eye-catching black spot, hence the name "black-eyed peas." They have an earthy flavor that complements salty foods like ham and bacon.
3. Cannellini Beans
Also known as white Italian kidney beans, these cream-colored beans are one of the most common types of beans. They are a popular addition to soups, salads, and many Italian dishes.
4. Chickpeas (Garbanzo Beans)
They have a round shape and a firm texture, making them a great salad topping.
5. Great Northern Beans
This is another type of white bean that is often mistaken for cannellini or navy beans
6. Kidney Beans
These beans are known for their vibrant red skin and white interior. They have a mild flavor, and make the perfect addition to any chili recipe.
7. Lima Beans
These beans get a bad rap, but there's actually so much to love when it comes to lima beans. They can be white, creamy, or green in color.
8. Pinto Beans
Pinto beans have an orange-pink color with rust-colored specks
9. Fava Beans
Fava beans, or broad beans, can be difficult to work with. They require that you remove them from their pods and then blanch them in order to get the skins off.
10. Navy Beans
This bean goes by many names: haricot, pearl haricot beans, white pea bean, and Boston bean. They have a mild flavor and creamy texture, and similar to Great Northern Beans, they do a great job of absorbing the flavors around them.
11 Adzuki Beans
These small, round red beans , Like other legumes, they're protein-packed and high in fiber.
Edamame are young soybeans which are usually eaten while still inside the pod.
13. Cranberry Beans
Rounding out the list are these striking cream-colored beans with red speckles. Also known as borlotti beans, cranberry beans have a creamy texture and a nutty flavor.
Soybeans are dried and beige in color.
15. Mung Beans
These beans are one of the most consumed types in the world. They are small, round, and green with a white stripe going through them. They have a mild flavor and a starchy texture
climatic conditions and soil type
Common beans grow within a range of temperatures of 17.5-27°C. Above 30°C flower buds are likely to fall and seeds are rarely formed at temperatures over 35°C. They are sensitive to night frost. Common beans are usually grown at altitudes between 600 - 1950 m in many tropical areas. A moderate well-distributed rainfall is required (300-400 mm per crop cycle) but dry weather during harvest is essential. Drought or waterlogging are harmful. Climbing cultivars will give economic yields in areas of high rainfall but the dwarf types appear to be more sensitive to high soil moisture levels. Suitable soil types range from light to moderately heavy and to peaty soils with near-neutral pH and good drainage. Common bean is susceptible to salinity.
The optimum temperature range for growing French beans is 20-25°C, but can be grown in temperatures ranging between 14 and 32°C. Extreme temperatures result in poor flower development and poor pod set. However, French beans mature faster in warmer areas. French beans can be grown between 1000 and 2100 metres above sea level. Rainfed cultivation is possible in areas with well distributed, medium to high annual rainfall (900-1200 mm) but to maintain a continuous production especially during the dry season, irrigation is essential. During the dry season up to 50 mm of water per week is required. This could be applied through furrow or overhead irrigation. French beans grow best on well drained, silty loams to heavy clay soils high in organic matter with pH 5.5-6.5.
The common bean is used as a pulse and green vegetable eaten fresh or cooked. The beans can be dried, cooked in sauce and canned .The common bean is used as a pulse and green vegetable eaten fresh or cooked. The beans can be dried, cooked in sauce and canned.
Beans are among some of the oldest cultivated vegetables. There are various types of beans that differ with shapes, sizes, taste and nutritional facts. Kidney beans, pinto beans, broad beans, fava beans, lima beans, etc. are some of the different types of beans. Each of them is loaded with dietary fibers, proteins and major vitamins and minerals like vitamin A, vitamin C, potassium, calcium and magnesium. The amount of the above given nutrients varies from one type of bean to other. Beans are very low in fat and cholesterol and they also help to lower the bad cholesterol in the body. Since they are high in proteins, they make an excellent meat substitute for vegetarians. They are extremely low in calories and hence are a favorite food among the calorie conscious people. Before knowing more about beans nutritional value, let us take a look at some figures related to nutrition in beans.
Countries where beans is grown
The main producing countries in the region are Kenya, Tanzania, Uganda, and more recently Rwanda. In Kenya, most of the crop is grown by smallholders and virtually all is exported to Europe. Estimates indicate that up to 50,000 smallholder families are involved in French bean production in Kenya.
The growth habit of common beans varies from determinate dwarf or bush types to indeterminate climbing or pole cultivars. Bush beans are the most predominant types grown in Africa. However, improved climbing beans introduced to Rwanda in the 80's have since spread to other countries in the region. They are particularly grown in areas with limited land and high human population.
Common beans are warm-season crops and should be planted after all danger of frost has passed and the soil has warmed. Beans will grow best at soil temperatures between 15.5 and 29°C (60–85°F) and are sensitive to cold temperatures and frosts. Beans will grow best in a fertile, well-draining soil with a pH between 6.0 and 6.75 Beans will perform best in full sunlight.
Beans should be direct seeded in the garden in when the soil has reached a temperature of at least 15.5°C (60°F), with the optimum temperature for germination being between 15.5 and 29°C (60–85°F). Planting at cooler temperatures leads to slow germination and promotes seed rotting. Seeds should be planted 2.5–3.5 cm (1–1.5 in) deep. Bush beans should be planted 5–10 cm (2–4 in) apart allowing 0.6–0.9 m ( 2–3 ft) between rows. Pole beans can be planted in both row and hills. In rows, seeds should be spaced 15–25 cm (6–10 in) apart allowing 0.9–1.2 m (3–4 ft) between rows. For a continuous harvest of beans over the summer months, make new plantings every 2–3 weeks.
Poles and trellises
Pole beans should be provided with a pole or trellis to climb on to support the weight of the pods and allow light to penetrate to all parts of the plant, helping to prevent disease. Bean poles should have a rough surface to help the plant to grip and should be 1.8–2.1 m (6–7 ft) long. Three or four poles can be used to form a tripod onto which the plants can be trained. Bean trellises can be constructed easily using posts (or a tripod arrangement of poles), wire and twine. Position a post at either end of the area in which you wish to plant a row of beans and connect with two lengths of wire. The first wire should be approximately 13 cm (5 in) from the ground, and the second 1.5–1.8 m (5–6 ft) from the ground. Finally, use the twine to create a V-shaped trellis by tying the twine to the bottom wire, bringing it up to the top wire and looping it back down around the bottom wire. Continue to zigzag the string all the way along the wires to the second support before tying the twine off. A rough textured twine is best as it will encourage the plant to climb and twine around it. Pinch back the growing tips of the plants once they reach the top support to encourage the plant to branch.
Mulching with straw and cut grasses helps conserve moisture, promote adventitious root development and enhances tolerance to bean fly maggot damage.
Beans are excellent for intercropping with other food crops, such as maize, potatoes, celery, cucumber and can help supply the other crops with nitrogen to a limited degree. Longer season varieties of beans can fix higher amounts of nitrogen than short season varieties. Intercropping with chives or garlic helps repel aphids (KIOF - personal communication).
A regular water supply is essential for French beans as moisture affects yields, uniformity and quality. Water stress during flowering reduces yields, as does waterlogging. Irrigation in dry spells is recommended as 35 mm per week at planting and 10 days post emergence, followed by 50 mm per week thereafter till end of production.
Beans are generally ready for harvest approximately two weeks after bloom. The beans should be harvested just before the seeds are mature and before they form bumps on the pod. The pods should be firm and snap when they are bent. Pick beans every 2–3 days to ensure the plants remain productive. Pinch beans rather than pulling to avoid damaging the plant. Cut pole beans from the plant using scissors.
Pole beans planted beneath a trellis
Bean tripod and trellis
CABI Crop Protection Compendium. (2008). Phaseolus vulgaris datasheet. Available at: http://www.cabi.org/cpc/datasheet/40626. [Accessed 06 November 14]. Paid subscription required. Drost, D. (2010). Beans in the Garden . Utah State University Cooperative Extension. Available at: https://extension.usu.edu/files/publications/publication/HG_Garden_2005-08.pdf. [Accessed 06 November 14]. Free to access. Lerner, B. R. (2001). Growing Beans in the Home Vegetable Garden. Purdue University Cooperative Extension Service. Available at: http://www.hort.purdue.edu/ext/ho-175.pdf. [Accessed 06 November 14]. Free to access. Schwartz, H. F., Steadman, J. R., Hall, R. & Forster, R. L. (2005) Compendium of Bean Diseases. Available at: http://www.apsnet.org/apsstore/shopapspress/Pages/43275.aspx. Available for purchase from APS Press.
Common Pests and Diseases
Category : Fungal
Alternaria leaf spot
Symptoms of Alternaria leaf spot on bean leaves and pods
Small irregular brown lesions on leaves which expand and turn gray-brown or dark brown with concentric zones; older areas of lesions may dry out and drop from leaves causing shot hole; lesions coalesce to form large necrotic patches
Plant beans in fertile soil; foliar fungicide application may be required
Colletotrichum lindemuthianum (Glomerella lindemuthiana)
Bean plants showing canopy symptoms
Anthracnose symptoms on beans and pods
Anthracnose symptoms on bean pods
Close-up view of a bean pod, displaying symptoms of bean anthracnose
Close-up of anthracnose lesion on bean pod
Anthracnose symptoms on bean pod
leaf showing symptoms of beans anthracnose
Close-up view of a bean leaf petiole, displaying symptoms of bean anthracnose
Symptoms of bean anthracnose
Anthracnose symptoms on bean pods
Small, dark brown to black lesions on cotyledons; oval or eye-shaped lesions on stems which turn sunken and brown with purple to red margins; stems may break if cankers weaken stem; pods drying and shrinking above areas of visible symptoms; reddish brown spots on pods which become circular and sunken with rust colored margin.
Plant resistant varieties; use certified disease free seed; avoid sprinkler irrigation, water plants at base; plow bean crop debris into soil.
Rust pustules on bean leaf
Telia of bean rust
small yellow or white spots due to rust disease
Bean leaves showing "green island effect" due bean rust disease
Close-up view of the pycnium of bean rust
Symptoms on beans stem
Initial symptoms of rust disease
Rust disease infected plants
Field of dry beans displaying prominent symptoms of bean rust
Aecia of bean rust (Uromyces appendiculatus) on the stem
Teliospores formed on infected leaves
Rust symptoms on bean pod
Defoliation of bean leaves due to rust disease
Telia of bean rust (Uromyces appendiculatus) on a bean leaf.
Initially the symptoms appear as small yellow/white spots on leaves. Later the spots become enlarged and shows raised brick red rust pustules (uredinia). Normally this pustules are surrounded by a yellow halo. Premature leaf drop may occur if the disease is severe.
Grow available resistant varieties. Remove and destroy the infected crop debris. Follow crop rotation. Keep the field free from weeds. If the disease is severe, spray suitable fungicide.
Black root rot
Symptoms of black root rot (Thielaviopsis basicola)
Elongated red-purple lesions due black root rot on melon seedling
black root rot (Thielaviopsis basicola) symptom
Elongated red-purple lesions on root tissue which turns dark gray to black; lesions coalesce to form large dark areas on roots and stems; deep lesions can cause stunted growth, wilting leaves, defoliation and plant death.
Rotate crops with non-susceptible grasses; avoid excess irrigation or drought stress.
Fusarium root rot
Roots of drybeans showing advanced symptoms of Fusarium root rot caused by Fusarium oxysporum f.sp. phaseoli.
Bean plant showing symptoms of fusarium wilt
Young plants stunted with chlorotic leaves; older plants with chlorotic leaves and some leaf drop; severely decayed roots which are hollow and dry.
Practice long term crop rotation; avoid over or under watering plants; some bean varieties exhibit some tolerance.
White mold (Sclerotinia timber rot)
Wilting of a dry bean plant in the field, an initial symptom of infection with white mold
Wilting and death of the bean canopy, an advanced symptom of infection with white mold
Advanced symptoms of white mold
White mold symptoms on bean plants caused by Sclerotinia sclerotiorum
Fallen blossoms of dry bean that have been colonized by white mold
Mycelium and sclerotia of white mold
Advanced symptoms of white mold (Sclerotinia sclerotiorum) on the branches and pods of a bean plant.
White mold on bean stem and branches
Field infested with white mold
Symptoms in advance stage
Apothecia of white mold (Sclerotinia sclerotiorum) and fallen leaves of dry bean that have been colonized by white mold.
Bean pod and flower colonized by white mold
Flowers covered in white, cottony fungal growth; small, circular, dark green, water-soaked lesions on pods leaves and branches which enlarge and become slimy; cottony white growth may be visible on lesions during periods of high humidity; death of branches and/or entire plant.
There is no true immunity to white mold in any bean varieties; rotate crops with non-hosts like cereals and corn; plant rows parallel to direction of prevailing winds to prevent spread of disease from secondary hosts nearby; avoid excessive nitrogen fertilizer; use a wide row spacing.
Category : Bacterial
syn. Xanthomonas axonopodis
Symptoms on lower surface of leaf
Symptoms on both upper and lower surface of leaves
Bacterial blight of beans
Symptoms of bacterial blight on bean foliage
Symptoms of common bacterial blight
Common bacterial blight water soaking on dry bean leaf, canopy symptoms
Lesions of common bacterial blight
Symptoms on bacterial blight on pods
common bacterial blight water soaking on dry bean leaf
Common bacterial blight water soaking lesions on dry bean pods, disease
Leaf lesions caused by bean bacterial blight
Symptoms of bacterial blight on bean leaves
Water-soaked spots on leaves which enlarge and become necrotic; spots may be surrounded by a zone of yellow discoloration; lesions coalesce and give plant a burned appearance; leaves that die remain attached to plant; circular, sunken, red-brown lesion may be present on pods; pod lesions may ooze during humid conditions.
Plant only certified seed; plant resistant varieties; treat seeds with an appropriate antibiotic prior to planting to kill off bacteria; spray plants with an appropriate protective copper based fungicide before appearance of symptoms.
Bacterial brown spot
Bacterial brown spot on dry bean- branch lesions.
Lesions of bacterial brown spot on a bean pod.
Bacterial brown spot disease symptoms
bacterial brown spot on dry bean, canopy shot - hole damage, early necrosis, disease, Pseudomonas syringae pv. syringae
Early shot-hole lesions on leaves of dry beans due to bacterial brown spot
"Water soaking" and necrosis on bean leaves, due to infection with bacterial brown spot disease
Infected bean pods
Cupping of young leaflets of dry beans, a symptom of bacterial brown spot disease
Symptoms of bacterial brown spot
Symptoms of bacterial brown spot (Pseudomonas syringae pv. syringae) on foliage of dry beans.
Small, dark brown necrotic spots on leaves which may be surrounded by a zone of yellow tissue; water soaked spots on pods which turn brown and necrotic; pods may twist and distort in area of infection.
Plant only certified seed; rotate crops regularly; remove crop debris from field after harvest.
Pseudomonas savastanoi pv. phaseolicola
Halo blight "water soaking" on a mature pod of red kidney beans
Halo blight "water soaking" on a young bean pod
halo blight symptoms on lower surface of common bean leaflet, note small water-soaked spots
Halo blight chlorosis on bean leaves
halo blight symptoms on upper surface of common bean leaflet, note circular yellow spots
Chlorosis and isolated lesions of halo blight on dry beans.
Halo blight chlorosis
Halo blight symptom
Halo blight "water soaking" on a mature bean pod
Symptoms of halo blight on bean pods
Small water-soaked spots on underside of leaves which turn necrotic and become visible on upper surface; lesions may develop an area of chlorotic tissue around the spots; lesions on expanding leaves may cause distorted leaves; red-brown lesions may be visible on pods; pod lesions may ooze or may turn tan in color.
Plant disease free seed or treat seed with an antibiotic to reduce levels of bacterium; rotate crops to non-hosts every 2 years; plow bean debris deeply in soil after harvest.
Category : Fungal, Oomycete
Drybean seedlings showing symptoms of Pythium damping off caused by Pythium spp.
Roots of drybean seedlings showing early symptoms of Rhizoctonia root rot caused by Rhizoctonia solani.
elongated sunken reddish-brown lesions on roots and stems at or below the soil line
Death of seedling due to damping off
Drybean plants showing symptoms of Rhizoctonia and Pythium root rots caused by Rhizoctonia solani and Pythium spp. respectively in the field.
Roots of drybeans showing advanced symptoms of Rhizoctonia root rot caused by Rhizoctonia solani.
Fusarium damping-off (Fusarium solani) symptoms
Damping Off on Snap Bean (Pythium and Rhizoctonia) Collapse of the lower stem area.
Rhizoctonia damping-off, blight and rot (Rhizoctonia solani) symptoms
The pathogens attack any stage of crop beginning from seed rot; damping off of seedlings; or stunting, yellowing and death of older plants. Visible symptoms are the appearance of elongated sunken reddish-brown lesions on roots and stems at or below the soil line. Further the lesions girdle the stem, causing the death of the plant. Older plants may show little indication of the disease, although yields may be reduced. The pith may turn brick- red if invaded by the fungus.
Follow crop rotation with non host crops. Sow the seeds in warm soil with well prepared seed bed and proper depth. Treat seeds with a suitable fungicide.
Category : Viral
Bean common mosaic virus (BCMV)
Bean common mosaic necrosis virus (BCMNV)
Drybean leaflets showing symptoms
Leaves of a common bean plant showing symptoms of primary leaf necrosis caused by the Bean Common Mosaic Virus (BCMV).
A common bean plant showing symptoms of black root wilting caused by the Bean Common Mosaic Virus (BCMV).
Bean common mosaic virus symptoms on bean foliage
Pods of common beans showing symptoms of black root necrosis caused by the Bean Common Mosaic Virus (BCMV).
A common bean plant showing symptoms of stunting caused by the Bean Common Mosaic Virus (BCMV)
Bean yellow mosaic on a bean leaflet showing the mosaic pattern
Dry bean plants showing symptoms of Bean Common Mosaic Virus.
A common bean plant showing symptoms of black root necrosis caused by the Bean Common Mosaic Virus (BCMV).
A common bean leaf of an infected plant showing leaf cupping and mosaic
Bean yellow mosaic virus on a bean leaflet showing the mosaic pattern as caused by the Bean Common Mosaic Virus (BCMV).
Mottled dark and light green patterns on leaves; leaves may be distorted; yellow dots may be present on leaves; growth of plant may be reduced.
Plant only virus-free seed; plant resistant varieties.
Category : Insects
Aphids (Cowpea aphid, Pea aphid, etc.)
Black Bean Aphid Aphis fabae
The aphids are tended by ants
Winged aphids, the vectors of Bean Common Mosaic Virus (BCMV), on a bean leaflet.
Close-up of Black Bean Aphids (Aphis fabae) colony
Aphids on lower surface of leaves
Aphid infestation on bean plant
Cowpea aphid (Aphis craccivora) infestation
Ladybird beetle feeding on bean black aphids
Small soft bodied insects on underside of leaves and/or stems of plant; usually green or yellow in color, but may be pink, brown, red or black depending on species and host plant; if aphid infestation is heavy it may cause leaves to yellow and/or distorted, necrotic spots on leaves and/or stunted shoots; aphids secrete a sticky, sugary substance called honeydew which encourages the growth of sooty mold on the plants.
If aphid population is limited to just a few leaves or shoots then the infestation can be pruned out to provide control; check transplants for aphids before planting; use tolerant varieties if available; reflective mulches such as silver colored plastic can deter aphids from feeding on plants; sturdy plants can be sprayed with a strong jet of water to knock aphids from leaves; insecticides are generally only required to treat aphids if the infestation is very high - plants generally tolerate low and medium level infestation; insecticidal soaps or oils such as neem or canola oil are usually the best method of control; always check the labels of the products for specific usage guidelines prior to use.
Armyworms (Beet armyworm, Western striped armyworm)
Adult of beet armyworm
Beet armyworm egg mass hatching
Damage due to early stage beet army worm larvae
Beet armyworm (Spodoptera exigua) egg mass covered with hairs.
Beet armyworm adult
Beet armyworm eggs
Larvae of beet armyworm
Beet army worm late instar larvae
Beet armyworm (Spodoptera exigua) on leaf
Singular, or closely grouped circular to irregularly shaped holes in foliage; heavy feeding by young larvae leads to skeletonized leaves; shallow, dry wounds on fruit; egg clusters of 50-150 eggs may be present on the leaves; egg clusters are covered in a whitish scale which gives the cluster a cottony or fuzzy appearance; young larvae are pale green to yellow in color while older larvae are generally darker green with a dark and light line running along the side of their body and a pink or yellow underside.
Organic methods of controlling armyworms include biological control by natural enemies which parasitize the larvae and the application of Bacillus thuringiensis; there are chemicals available for commercial control but many that are available for the home garden do not provide adequate control of the larvae.
Larvae feeding on leaf
Corn earworm (Helicoverpa zea) adults
Adult and larvae
Corn earworm on bean
Larvae damage leaves, buds, flowers, pods and beans; young caterpillars are cream-white in color with a black head and black hairs; older larvae may be yellow-green to almost black in color with fine white lines along their body and black spots at the base of hairs; eggs are laid singly on both upper and lower leaf surfaces and are initially creamy white but develop a brown-red ring after 24 hours and darken prior to hatching.
Monitor plants for eggs and young larvae and also natural enemies that could be damaged by chemicals; Bacillus thuringiensis or Entrust SC may be applied to control insects on organically grown plants; appropriate chemical treatment may be required for control in commercial plantations.
Bean leaf skeletonizer (Autoplusia egena) larva
Cutworm damage to bean seedling
Cutworm larva severing plant stem
French beans attacked by Helicoverpa armigera. Note the larvae within the bean.
Cutworm feeding on plant stem
Eggs of western bean cutworm (Striacosta albicosta)
Cutworms will curl up into a characteristic C shape when disturbed
Stems of young transplants or seedlings may be severed at soil line; if infection occurs later, irregular holes are eaten into the surface of fruits; larvae causing the damage are usually active at night and hide during the day in the soil at the base of the plants or in plant debris of toppled plant; larvae are 2.5–5.0 cm (1–2 in) in length; larvae may exhibit a variety of patterns and coloration but will usually curl up into a C-shape when disturbed.
Remove all plant residue from soil after harvest or at least two weeks before planting, this is especially important if the previous crop was another host such as alfalfa, beans or a leguminous cover crop; plastic or foil collars fitted around plant stems to cover the bottom 3 inches above the soil line and extending a couple of inches into the soil can prevent larvae severing plants; hand-pick larvae after dark; spread diatomaceous earth around the base of the plants (this creates a sharp barrier that will cut the insects if they try and crawl over it); apply appropriate insecticides to infested areas of garden or field if not growing organically.
Leafminer damage on bean plant leaf
leafminer fly (Liriomyza sp.) adult
An infested common bean leaf showing tracts of the leaf miner Liriomyza sp.
Larvae of leafminer
vegetable leafminer (Liriomyza sativae) on bean leaves
Tunnels caused by leafminer
vegetable leafminer (Liriomyza sativae) adult
leafminer fly (Liriomyza sp.) pupa
Thin, white, winding trails on leaves; heavy mining can result in white blotches on leaves and leaves dropping from the plant prematurely; early infestation can cause fruit yield to be reduced; adult leafminer is a small black and yellow fly which lays its eggs in the leaf; larvae hatch and feed on leaf interior.
Check transplants for signs of leafminer damage prior to planting; remove plants from soil immediately after harvest; only use insecticides when leafminer damage has been identified as unnecessary spraying will also reduce populations of their natural enemies.
Loopers (Cabbage looper, Alfalfa looper)
soybean looper (Thysanoplusia orichalcea) on dry beans
Looper on bean leaf
Large or small holes in leaves; damage often extensive; caterpillars are pale green with a white lines running down either side of their body; caterpillars are easily distinguished by the way they arch their body when moving; eggs are laid singly, usually on the lower leaf surface close to the leaf margin, and are white or pale green in color.
Looper populations are usually held in check by natural enemies; if they do become problematic larvae can be hand-picked from the plants; an organically acceptable control method is the application of Bacillus thuringiensis which effectively kills younger larvae; chemical sprays may damage populations of natural enemies and should and should be selected carefully.
Mexican bean beetle
Adult Mexican bean beetle
Mexican bean beetle damage to bean foliage
Adult beetle and damage to bean foliage
Eggs laid on underside of bean leaf
Mexican bean beetle larva
Bean plant infested with Mexican bean beetle larvae
Irregular patches of feeding damage on underside of leaves which causes the top surface of the leaf to dry out, giving the leaves a lacy appearance; insect will also damage flowers and small pods; pods may be damaged so badly that they drop from the plant; adult insect is an orange-brown beetle with black spots; larvae are fat-bodied grubs which taper at the end and are in rows of conspicuous spines
Some bean varieties may be less attractive hosts for the beetle, e.g. snapbeans are preferred hosts over lima beans; early varieties may escape damage form beetles beetle populations can be reduced by remove overwintering sites such as brush and leaves on the ground; handpick larvae and adults; brush eggs from leaves and destroy; apply insecticidal soap to leaf undersides if infestation is heavy
Stinkbugs (Consperse stinkbug, etc.)
Florida Preatory Stink Bug, Euthyrhynchus floridanus (beneficial insect)
Globular stinkbug on leaf
Predaceous anchor stink bug (Stiretrus anchorago) attacking green stinkbug nymph.
Stinkbug feeding on bean pod
Southern stinkbug feeding on bean leaf
brown stink bug (Euschistus servus) eggs
Stinkbugs infestation on bean leaves
Dark colored pinpricks on fruit surrounded by a lighter area that turns yellow or remains light green; stink bugs often carry pathogens in their mouthparts which can cause secondary infections and decay of fruit; adult insect is shield-shaped and brown or green in color; may have pink, red or yellow markings; eggs are drum shaped and laid in clusters on the leaves; larvae resemble the adults but are smaller.
Remove weeds around crop which may act as overwintering sites for stink bugs and practice good weed management throughout the year; organically accepted control methods include the use of insecticidal soaps, kaolin clay and preservation of natural enemies; chemical treatments are not recommended for tomatoes that are to be processed for paste or canning unless secondary infections with other pathogens are a concern.
Category : Mites
Spider mites (Two-spotted spider mite)
Spider mite symptoms on upper surface of leaves
Tropical spider mites necrosis to bean leaves on the field.
Spider mite infestation on bean foliage
Stippling injuries to leaves due to spider mites
Underside of a bean leaf showing spider mites.
Spider mite infestation on lower surface of leaf
Leaves stippled with yellow; leaves may appear bronzed; webbing covering leaves; mites may be visible as tiny moving dots on the webs or underside of leaves, best viewed using a hand lens; usually not spotted until there are visible symptoms on the plant; leaves turn yellow and may drop from plant.
In the home garden, spraying plants with a strong jet of water can help reduce buildup of spider mite populations; if mites become problematic apply insecticidal soap to plants; certain chemical insecticides may actually increase mite populations by killing off natural enemies and promoting mite reproduction.