(IPPM) in Vegetables - Vegetableipmasia.org

Resource Manual on IPPM in Rice
World Education Philippines, Inc.
a. Clear off all heavy trash and crop residue -such as cornstalks, dried-up tomato
vines, rocks, branches, etc. This removes old, diseased plants that harbor
insect pests, and makes it easier to work the ground. It is good practice to turn
under green manure crops.
b. Plow in light soils such as sandy loams and silts. Plow in heavy soils
containing large amounts of clay.
c. Disc plowed the ground immediately so as not to give it the chance to get hard
and dry after plowing.
d. Harrow disc ground to level.
2. Some Recommended Seedbed Preparation and Management Practices
a. Soil Sterilization
There are several ways of sterilizing soil, both as a preventive measure against
soil-borne diseases (such as damping-off) and as a method to control soilborne
diseases already present. A number of common practices is briefly
described below.
· Burning Organic Material on the Soil
A common method of soil sterilization is heating up the soil. The high
temperature will cause the death of many micro-organisms, including
pathogens on the top of the soil and insect pests with soil-dwelling stages,
such as cutworms. Soil sterilization is commonly practiced by burning
straw, or dry grass, leaves or waste materials on the nursery beds before
sowing. It should be noted that straw burns very shortly and the heat does
not penetrate deep enough into the soil. This may result in only a very thin
layer of the soil being sterilized A substantial amount of slow-burning but
high temperature output material would be required on the soil, e.g. wood
rather than grass. Rice husk is preferred to straw because it burns slower
and heat penetrates deeper into the soil, resulting in better sterilization.
· Solarization
Another soil sterilization method is solarization with the help of the sun.
Solarization of seedbeds can control soil-borne diseases, weed seeds and
some nematodes including rootknot nematodes. However, not all pests are
controlled.
To solarize soil, the soil is covered with clear polyethylene or plastic
sheets. The best time is during the hot season, when there is plenty of sun.
The sun heats up the soil through the plastic and the plastic sheet keeps the
heat inside the soil. Usually, the sheets should be left on the soil for at least
4 weeks, depending on the season (hours of sunshine and temperature) and
the area (lowland or highlands). The soil should be moist before the plastic
sheets are placed and the sheets should be properly fixed on the sides to
avoid loosing heat. There is also a need to check the polyethylene sheets
for holes and to repair them where necessary. Ploughing the soil before
applying the sheets seems to help break up crop left-overs and bring
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