The document discusses different methods of fertilizer application and occupational safety standards for fertilizer application. The main methods of fertilizer application discussed are broadcast, localized application, foliar application, applied with seed, and fertigation. The occupational safety standards cover proper handling of fertilizers, use of protective equipment, transportation, and decontamination procedures especially for toxic fertilizers.
2. Villegas and Malixi (1977) stated that to
get the maximum benefit, the fertilizer must
be applied where the plant can readily
absorb it. Proper placement of fertilizer will
provide an efficient and continuous supply
of plant nutrients and will prevent salt
injury to the seedlings. The following are
the different methods of fertilizer
application:
3. 1. Broadcast method
The fertilizer material is applied
uniformly over the entire area before
planting or while the crop is growing.
Topdressing refers to the broadcast
application on growing crops. Uniform
distribution of the fertilizer enables the
safe application of large quantities of
fertilizer without injuring the crop.
However, it may reduce fertilizer
efficiency because of fertilizer fixation or
by volatilization.
4. 2. Localized Application
The fertilizer is applied close to the
seed or plant, either in a band adjacent to
the plant rows (side dressing) or by the
plow-sole application. In the plow-sole
method, the fertilizer is covered lightly
with soil before seeding or planting.
Localized application is essential for high
rate applications of high analysis
fertilizers. This method is commonly
used for most vegetables.
5. 3. Foliar application
Plant nutrients may be applied to
the aerial part of the plant. The dissolved
nutrient must penetrate the cuticle of the
leaf or the stomata and then enter the
plant cells. This method is usually
employed only in applying
micronutrients. Marginal leaf-burn could
occur with the application of high
concentrations of fertilizer.
6. 4. Applied with the seed – Fertilizer is
broadcast together with the seeds or the
seeds are coated with fertilizer using an
adhesive such as selloffs or gum Arabic.
5. Fertigation – This involves dissolving the
fertilizer materials in water and
then applying it with the use of a sprinkler.
8. Handling of Fertilizers
•Fertilizers shall not be left unattended to
when not in use;
•Fertilizers shall be prepared by mechanical
means in closed vessels. However, if closed
mechanical preparation is impracticable:
•Tall vessels and long-handled implements
shall be used to reduce the risk of
splashing;
•Vessels shall not be filled to avoid
splashing.
9. • Unbreakable vessels shall be used in the
preparation of toxic fertilizers.
• Protective clothing, like boots, gloves, goggles,
and face shields shall be used when mixing,
diluting, spraying, or spreading toxic
fertilizers.
• Spillage of fertilizers and contamination shall
be prevented. Spillage shall be thoroughly
cleaned immediately.
• Whenever practicable, apply toxic fertilizers by
mechanical means.
10. •Immediately after spraying toxic fertilizers
in a greenhouse, the employersshall:
a. requires all persons entering the
greenhouse to be properly protected;
b. post notices on all gates of the
greenhouse stating how long the area is to
remain closed before the entry of persons
without proper protection are allowed.
11. • Workers using toxic fertilizers shall not:
a. blows out blocked spray pipes or nozzle
with the mouth;
b. spray or spread fertilizers against the
direction of the wind. •
• Decontaminate the exterior of all tanks
and containers in which toxic fertilizers
are stored.
• Securely close the opening of all tanks and
containers in which toxicfertilizers are
12. •Tanks and piping shall:
a. be regularly checked for damage and
b. Be provided with stop valves or other
devices that can effectively prevent or
limit the escape of the substance.
•Fertilizers shall be transported only in
suitable vehicles to ensure protection to
the driver and other users of the
vehicles.
13. •Handling of organic fertilizers shall be
by mechanical means to minimize direct
contact with such fertilizers or in the
absence of mechanical means, proper
protection during handling shall be
required. (14) Personal protective
equipment shall be provided too, and
used by workers when applying mineral
fertilizers.
