2. Stemborer: Batocera rufomaculata  (Cerambycidae : Coleoptera)

Distribution and Status: India, Bangladesh

Host range : Mango, rubber, jack-fruit, fig, papaya, apple, eucalyptus and mulberry, morings and silk cotton.

Damage symptoms

The grubs feed by tunneling the bark of branches and main stem. Shedding of leaves and drying of terminal shoots takes place in early stage of attack while damage to main stem causes tree death.

Bionomics : Eggs laid singly on the bark or cracks and crevices on the tree trunk or branches. Incubation period: 1-2 weeks. Grubs yellow, grub period 6 months, and pupal period is 19-36 days.  Adults grey with two pink dots and lateral spine on the thorax with a longevity of 6 months.

Management

• Grow tolerant mango varieties viz., Neelam, Humayudin
• Remove and destroy dead and severely affected branches of the tree
• Avoid injury at the base of trunk while pruning
• Remove alternative hosts like moringa, silk cotton in the near vicinity.
• During off-season, apply absorbent cotton soaked in 10 ml monocrotophos 36 SL per tree  by padding without unnecessarily injuring the trunk.
• Use a needle or long wire to pull out the grubs from the bore holes.  The bore holes may be filled with  DDVP @ 5 ml or monocrotophos 36 WSC 10 to 20 ml or one celphos tablet (3 g aluminum phosphide) or apply carbofuran 3G 5 g per hole and plug with clay + copper oxychloride paste.
• Swab Coal tar + Kerosene @ 1:2 or Carbaryl 50 WP 20 g / L (basal portion of the trunk - 3 feet height) after scraping the loose bark to prevent oviposition by adult beetles.