Several species of leafminers may attack a wide range of vegetable and ornamental crops in the field and in the greenhouse.

2. Presentation on
LEAF MINER

3. Introduction (Identification)
Flies of Order Diptera
Wide host range (vegetable, fruits & ornaments)
Recently known as a key pest of potato in central region of Nepal
Important sps are:
1) Liriomyza trifolii (unofficial 'serpentine' leafminer)
2) L. brassicae (official 'serpentine' leafminer)
3) L. sativae (vegetable leafminer) &
4) L. huidobrensis (pea and potato leafminer)
All are similar in appearance except black and yellow markings

4. Introduction (Identification)
1) L. sativae-vegetable
leafminer
-shiny black on upper
surface
-area between the eyes
yellow
-area just behind eyes black
2) L. trifolii
-more grayish upper thorax
-area behind the eyes is
mostly yellow
3) L. Brassicae
similar to L. sativae
L. huidobrensis-pea leaf
miner
-slightly larger
-normally darker colour

5. All have similar life history except pea leafminer ( slighty longer)
Eggs laid in leaves & oviposition punctures leaves to form
'stipples'
Opt. Temp
r
21°C - 32°C (feeding & egg laying)
 Egg-laying reduced below 10°C
After 2 - 3 days of incubation, eggs hatch
Larvae tunnel within the leaf tissue forming mine
Pupae can survive for up to 90 days when temperatures are cool or
host plants are not available
Life cycle 14 days at 30°C or as long as 64 days at 14°C
Mating, egg-laying, larval emergence from leaves and adult
emergence from pupae tends to occur mostly in the morning
Biology

6. Biology (Life cycle interval)

7. Life cycle of Leafminer fly

8. Adult female punctures leaves for
feeding & oviposition
Feeding & oviposition ratio- 6:1 to
14:1
Male also uses feeding punctures
made by females
Larvae feeding on mesophyll region
leaving a serpentine structure (mines)
Nature of Damage

9. Reduce yield, fruit size &
condition of sunburn may prevail
Heavily mined leaves have large
whitish blotches or speckles between
0.13 and 0.15 mm in diameter.
Premature dropping of injured
leaves
Nature of Damage

10. beet leaf cucumber
Nature of Damage (Gallery)
pea
bean cucumberpotato

11. Sanitation
Remove plant debris/ weeds
Removal of infected plant material
Management
Tolerant varieties
Use tolerant varieties
Susceptible varieties have to be grown in isolation

12. Management
Mechanical control
Use yellow sticky trap [2m x 50cm
white polythene sheet painted with
the glue prepared by well mixed
wood gum (0.5 litre) and yellow
dye (20g)] in the crop field for
monitoring and mass trapping
purposes.
Use of net.

13. Crop Rotation
Alternating leafminer susceptible crops with resistant crops
Leaving greenhouses empty during the winter
Management
Weed Management
Remove wild host plants
Maintain weed free condition in field
Pheromone Lure
Tomato leaf miner lure

14. Parasitic wasps Diglyphus isaea & Dacnusa sibirica
Diglyphus works better in the summer & Dacnusa in the winter
Fig. Diglyphus isaea Fig. Dacnusa sibirica
Management (Biological)

15. Management (Botanical)
Apply 1-1.75 kg fine ash of Lantana camera per 200 sq m plot;
Neem product- Margosom (0.15% w/w Azadiractin)@ 5ml/litre
of water
Spray fruit extract of chinaberry Melia azedarach as a feeding
deterrent to adults and to reduce oviposition rates.

16. Apply abamectin 2% EC @ 1.5ml per litre water at 3-4 days
interval. Abamectin is a biopesticide derived insecticide seems to
kill the leafminers but not their predators.
Spray Nuvan 76% EC (dichlorovos) @ 1ml per litre water or
Deltamethrin 2.8% EC @ 1ml per litre water for managing
adults.
Management (Chemical)