Aphid and Sawfly

Aphid and Sawfly

1. Rose aphid, Macrosiphum rosaeformis (Aphididae: Hemiptera)

Distribution: In India this aphid has been reported from rose from Punjab, Delhi, Mysore, Andhra Pradesh and Nilgiri hills

Host: Rose

Damage:
  • The aphids suck the sap from the tender parts
  • Particularly injurious to tender buds, resulting in the disfigurement and withering of flowers
  • A black fungus also develops on the honey dew giving ugly appearance to the plant
  • Deteriorates the market value the produce.
Identification:

  • Small (about 2.5mm long) wingless aphids having large red eyes, black cornicles and a yellowish green tip of abdomen.
21.1

Life cycle:

  • The pest is active from November to April in North India.
  • Nymphal development of non winged forms is in 11-14 days and of winged forms in14-19 days.
  • The growth is quickest in March.
  • Population starts increasing from November and is highest during March.
  • The population starts declining from April as the temperature starts increasing.
  • There is an increase in winged forms from December on wards with peak in March (90% alates)
  • The pest multiplies most rapidly in late spring and with the increasing in temperature its population declines.
Management:
  • The pest can be controlled by spraying the crop with oxy- demeton methyl (0.025%) or phosphamidon (0.03%) or malathion (0.05%) as soon as the attack is noticed.
  • Natural enemies like coccinellids, syrphids, chrysopids, etc. also take care of these aphids
  • Avoid application of insecticides when these natural enemies are active.
2. Ground nut aphid, Aphis craccivora (Aphididae: Hemiptera)

Distribution: Through out India.

Hosts: Ground nut, rose, Bougainvillea spp and many other plants of economic importance.

Identification: Adults are black or brown with variable size

Damage:
  • Both nymphs and adults suck the cell sap from tender plant parts.
  • Downward cupping of leaves and premature drop of flowers.
Life cycle:
  • The offsprings of winged form may be wingless.
  • Reproduction is parthenogenetic and viviparous
  • Each female can produce 8-30 young ones in a life span of 10-12 days.
  • Nymphs pass through four moults and become adult in 5-8 days.
  • Apterous females start producing brood within 24h of attaining the stage.
  • Pest breeds throughout the year
  • Both alatae as well as apterae forms are present.

Management:
  • Same as for rose aphid
3. Rose sawfly, Arge fumipennis (Argidae: Hymenoptera)

Host: rose

Damage:
  • Damage is caused by larvae
  • feed voraciously on the leaves and cause complete defoliation
  • Female makes an ovipositional slit on the stem and side branches with the help of saw like ovipositor
Identification:
  • Newly emerged larvae are green in colour with black head and thoracic legs
  • The adults on emergence are dull in colour which soon changed into shining black orange in colour.
  • Males are lightly smaller in size than females.
21.2

Life cycle:
  • The pest appears during first week of July with the onset of monsoon and remains active through out the rainy season
  • Newly emerged larvae feed on leaves in groups
  • Larval development is completed in about 15 days
  • Five larval instars.
  • Pupate in debris in protected silicon cocoons.
  • Papul period lasts for 1-2 days.

Management:
  • Apply malathion (0.05%) or carbaryl (0.1%).
  • Repeat the spray after 10 days if required.
Last modified: Saturday, 3 March 2012, 8:26 AM