Preventive Control

Natural enemies

Parasitoids

1. Native parasitic wasps

Predators

1. Damselfly
2. Dragonfly
3. Lacewing
4. Minute pirate bug
5. Spider

Monitoring

Start monitoring GLH in the seedbed up to panicle initiation. To monitor, randomly select 20 hills across the paddy. Monitor at least once a week. Visual inspection, sweep nets, sticky boards, and light traps can be used to detect its population. The sweep net is the most practical method because it is effective in catching GLH which normally feed on the upper portion of the plant. If no sweep net is available, tap the plants and count the adults and nymphs that fall in the water. The threshold levels are: 3 GLH per sweep and 6 GLH adults per hill (PhilRice, 1999: p. 58).

Management and cultural practices

1. Grow rice only two times in a year to have a rice-free period. This will suppress the virus-infected green leafhopper (GLH) population.
2. Plant together with other farmers in the area. Plant early maturing and resistant varieties (many rice varieties are now commercially available that are resistant to GLH). Although early maturing and resistant varieties reduce the GLH population, this will not guarantee viral infection prevention (Villareal, 1999).
3. Uproot, burn or plow under infected rice stubble, ratoons, weeds, and other rice residues.
4. Prepare land thoroughly and practice continuous water submergence, if field is irrigated.
5. Prepare seedbeds away from weedy or grassy areas. Get rid of weeds and grasses surrounding rice fields. Seedbeds must be located in areas not close to sources of light in homes or electric posts so as not to attract virus-infected hoppers (Reissig, et. al., 1986: pp. 200-216).
6. Cover seedlings (seedbeds) with fine mesh nylon nets or mesh cloth to prevent GLH attack. Seedlings are most susceptible to viral infestation.