Soybean Diagnostic Key

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2,4-D Injury

Type: Physiological
Leaf Condition: Distorted, Stunted
Leaf Location: Entire, Young
Petioles Condition: Distorted, Short Or Stunted
Plant Size: Stunted
Flowercondition: Distorted
Field Distribution: Uniform, Random, Edges
Prior Environmental: Wind, High Temp, Pesticide Spray
Season: Early Vegetative, Mid To Late Vegetative, Flowering
Cropping System: Soybean Followed By Soybean, Conventional Till, Reduced Till

Type: Disease
Leaf Condition: Tip Burn, Distorted, Marginal Necrosis, Interveinal Necrosis, Complete Necrosis, Wilted, Brittle, Webbing On Leaves, Leaf Spot
Leaf Color: Patchy Yellow And Brown Areas
Leaf Location: Entire, Upper, Lower, Young, Mature
Pod Condition: Lesion
Main Stem: Necrotic Spots
Petioles Condition: Distorted, Lesion, Death
Petioles Color: Red
Flowercondition: Necrotic
Field Distribution: Random, Low Areas, Localized Area
Prior Environmental: Rain, Thunderstorm, High Temp
Season: Mid To Late Vegetative, Flowering, Pods Present
Cropping System: Soybean Followed By Soybean, Conventional Till, Reduced Till

Type: Physiological
Leaf Condition: Marginal Necrosis, Interveinal Necrosis, Stunted
Leaf Color: Yellow, Purple, Marginal Chlorosis, Interveinal Chlorosis, Complete Chlorosis
Leaf Location: Entire, Edge, Young
Roots: Stunted
Petioles Condition: Short Or Stunted
Petioles Color: Red
Plant Size: Stunted
Field Distribution: Uniform, Random, Edges
Prior Environmental: Organic Soil, Rain, Dry, Wind, High Temp, Pesticide Spray
Season: Early Vegetative, Mid To Late Vegetative
Cropping System: Soybean Followed By Soybean, Conventional Till, Reduced Till

Type: Nutrition
Roots: Stunted, Poor Nodulation, Necrotic
Plant Size: Stunted
Field Distribution: Uniform, Low Areas, High Areas
Season: Early Vegetative, Mid To Late Vegetative, Flowering, Pods Present
Cropping System: Soybean Followed By Soybean, Conventional Till, Reduced Till

Type: Disease
Leaf Condition: Distorted, Complete Necrosis, Wilted, Brittle, Leaf Spot
Leaf Color: Black Irregular Spots, Patchy Yellow And Brown Areas, Marginal Chlorosis, Interveinal Chlorosis
Leaf Location: Entire, Upper, Lower, Young, Mature
Pod Condition: Lesion
Seed: Aborted, Shriveled
Main Stem: Necrotic Spots, Internal Discoloration
Petioles Condition: Distorted, Lesion, Death
Plant Size: Stunted
Field Distribution: Random, Low Areas, Localized Area
Prior Environmental: Rain, High Temp
Season: Flowering, Pods Present
Cropping System: Soybean Followed By Soybean, Conventional Till, Reduced Till

Scientific Name(s): Spodoptera exigua, Spodoptera frugiperda, Spodoptera ornithogalli

Type: Disease
Leaf Condition: Leaf Spot, Pustule
Leaf Color: Yellow, Orange Red, Interior Red Spots, Black Irregular Spots, Patchy Yellow And Brown Areas
Leaf Location: Entire, Upper, Lower, Young, Mature
Field Distribution: Random, Low Areas, High Areas, Localized Area
Prior Environmental: Rain, Wind, Thunderstorm, Cool Cloudy
Season: Early Vegetative, Flowering, Pods Present
Cropping System: Soybean Followed By Soybean, Conventional Till, Reduced Till

Type: Disease
Leaf Condition: Interveinal Necrosis, Leaf Spot, Pustule
Leaf Color: Yellow, Interior Red Spots, Bleached, Black Irregular Spots, Patchy Yellow And Brown Areas
Leaf Location: Entire, Upper, Lower, Young
Pod Condition: Lesion
Main Stem: Necrotic Spots
Petioles Condition: Distorted, Lesion
Field Distribution: Random, Low Areas, Localized Area
Prior Environmental: Rain, Thunderstorm, Cool Cloudy
Season: Mid To Late Vegetative, Flowering, Pods Present
Cropping System: Soybean Followed By Soybean, Conventional Till, Reduced Till