Question

Webbing of leaves, buds and flowers, bores into the pods and feeds on seeds are the damage symptoms of:

• A. Helicoverpa armigera
• B. Maruca vitrata
• C. Melanagromyza obtusa
• D. Exelastis atomosa

Hint:

When identifying pests based on damage symptoms, look for characteristic signs like webbing patterns, feeding marks, and specific plant parts affected.

Answer 1

The Correct Option is A

The described damage symptoms
webbing of leaves, buds and flowers, boring into pods, and feeding on seeds
are characteristic of Helicoverpa armigera, commonly known as the gram pod borer or cotton bollworm. This pest is known for:
Creating webbing on plant parts
Boring into pods
Feeding on developing seeds
Affecting a wide range of crops including pulses, cotton, and vegetables The other options can be eliminated because:
Maruca vitrata typically causes damage to flowers and pods but doesn't create extensive webbing
Melanagromyza obtusa is a stem borer that doesn't cause webbing
Exelastis atomosa is a pod fly that doesn't create webbing

Answer 2

Reasoning from larval feeding behaviour:
Newly hatched Helicoverpa armigera larvae are gregarious feeders that first web together leaves, buds and flowers with silk before dispersing, older larvae then bore into pods and consume the developing seeds from inside, this two-stage progression is diagnostic for this species.
Maruca vitrata larvae bore into pods and flowers but do not produce this extensive webbing. Melanagromyza obtusa is a stem and pod fly whose maggots mine internally without webbing, and Exelastis atomosa also lacks the webbing habit.
Only the described life-cycle pattern, webbing followed by pod-boring, matches Helicoverpa armigera.