Why Does My Soybean Have Unhealthy Looking Leaves?

Are there any water-soaked spots on leaves that enlarge and become necrotic?

Are there any tiny pale green spots with raised centers on both upper and lower leaf surfaces that develop raised pustules in the lesion center?

Do the leaves have reddish or pale yellow areas on their upper side and dusty orange blisters on the undersides?

Are there any small, angular, gray-brown spots with defined red-brown margins on leaves?

Are there singular, or closely grouped circular to irregularly shaped holes in the foliage?

are there irregular patches of feeding damage on the underside of leaves which causes the top surface of the leaf to dry out, giving the leaves a lacy appearance?

Do the upper leaves have light purple discoloration and a leathery appearance?

Do the leaves have pale areas on upper surfaces and "downy" patches underneath?

Are there any small, necrotic flecks on leaves that develop a chlorotic halo and expand into tan brown necrotic spots?

Are there any angular or circular green to gray spots with brown borders on leaves?

Water-soaked spots on leaves are caused by bacterial blight. The spread of the disease is greatest during humid, wet weather conditions. The copper spray will help in reducing the spread of the disease. If there are no new pods on the plant, you should remove the diseased plants.

Bacterial pustule is a bacterial disease prevalent in regions with warm temperatures and frequent rainfall during the growing season. Spray plants with an appropriate protective copper-based fungicide before the appearance of symptoms.

These symptoms indicate a fungal disease - Rust. Provide good air circulation around plants by thining them. Avoid making leaves wet when watering. Remove and destroy all garden debris before spring. All infected leaves should be removed. Spray leaves with sulfur early in the season to prevent rust or to treat mild infections.

These symptoms indicate fungal disease - Septoria leaf spot. This disease overwinter on old leaf litter, so rake up the leaves or bury them under a thick mulch in autumn. Copper sprays will help in controlling the spread. If defoliation occurs late in the season, it does plant little harm.

Beet armyworm causes irregularly shaped holes in the foliage. Organic methods of controlling armyworms include biological control by natural enemies that parasitize the larvae and the application of BTK spray (Bacillus thuringiensis).

Mexican bean beetle causes this type of damage. Handpick larvae and adults, and brush eggs from leaves and destroy them. Apply insecticidal soap to leaf undersides if the infestation is heavy.

Brown spot is a fungal disease that occurs during warm and wet weather. Plow crop residue into the soil after harvest. Rotate crops to a non-susceptible crop for at least one year. Apply an appropriate foliar fungicide to protect plants from bloom to pod fill.

Pale areas on upper surfaces of the leaves and "downy" patches underneath are caused by Downy mildew. This fungus spreads quickly during cool, wet nights and warm, humid days. Leaves will wilt and die. Remove and destroy all affected plant parts and encourage good air circulation around plants by thining them. Water plants early in the morning to make sure they dry before nightfall.

Cercospora leaf blight is caused by a fungus that can be introduced through infected seed and spread by wind or water splash. Plant only pathogen-free seed from a reputable nursery. Apply copper-based foliar fungicide if the disease emerges. Rotate crops to non-umbelliferous varieties.

These symptoms indicate a fungal disease - Cercospora leaf spot. This fungal disease only occurs in very warm climates. Spots develop a “frog-eye” appearance with light centers and dark edges. Spray plants with copper as soon as symptoms appear to prevent further symptom development.

If the leaves of your soybean are yellowing and wilting, the problem might be environmental. Overwatering causes root rot which causes leaves to wilt, nutrient deficiency shows as foliage discoloration or yellowing. Apply compost into the soil to increase organic matter and make soil drain better.