Stem Borer

Euzophera perticella

Stem Borer

Euzophera perticella

Introduction

• The brinjal stem borer, Euzophera perticella, is a significant pest affecting eggplant in Varanasi, Uttar Pradesh.

• Causes severe damage to brinjal crops, particularly near maturation, ratoon, and grafted crops.

• The endoparasitoid Pristomerus euzopherae is prominently associated with this pest.

Symptoms of Infestation

• Affected plants appear light yellow, drooped, withered, and wilted.

• Stunted growth, reduced plant vigor, and lower fruit-bearing capacity.

• Damage observed in patches across the field.

Incidence and Damage Progression

• Initial incidence: 13.5% stem damage in February (second fortnight).

• Gradual increase to 29.75% in March, 51.5% in April, 76.5% in May, and 89.7% in June.

• Nearly all plants affected by July.

Life Cycle

• Oviposition Period: 4-11 days.

• Egg Stage: 3-9 days, creamy and scale-like, laid singly or in batches.

• Larval Stage: 29-47 days (mean 38.40 days), four instars.

  • Neonate larvae: Light yellowish-green.

  • Third instar: Whitish with blackish hairs.

  • Fourth instar: Larger size (14.5–19.25 mm), brown sclerotized head, segmented body.

• Pupal Stage: 7-14 days, pupates within a cocoon inside the larval tunnel.

• Adult Stage:

  • Male longevity: 4-8 days.

  • Female longevity: 5-13 days.

  • Greyish-brown adults with transverse lines on forewings and white hindwings.

• Total life cycle: 35-76 days.

Endoparasitoid (Pristomerus euzopherae)

• First recorded in the second fortnight of April with 1.91% parasitization.

• Peak parasitization: 12.48% in July, followed by 7.73% in June.

Management Strategies

• Early detection and destruction of affected plants.

• Implementing integrated pest management (IPM) practices.

• Encouraging natural parasitoids to maintain pest populations below economic thresholds.

Ref: ICAR