Lec 11 Flashcards
The process of providing plants the conditions that will make them free of weeds, pests, and diseases.
Crop Protection
The growing stage between planting and flowering constitutes the longest stay in the field
and the most vulnerable period of the crop.
Weeds compete with the available moisture and
nutrients if left uncontrolled.
Pests and diseases multiply above the economic
threshold levels if left uncontrolled.
Crop Protection
Modification of cultural practices such as time of planting and crop rotation.
Cultural Control
Change in the environment of the crop and the pest which favors the survival of the crop such as flooding to kill insects and weeds.
Ecological Control
Introduction of certain insects which feed on pests, application of chemosterilants to render the male sterile, or planting of certain plants whose odor drive pests away.
Biological Control
Breeding and planting of pest resistant varieties.
Physiological Control
Application of chemicals to control weeds, pests and diseases.
Chemical Control
Use of flame for the selective burning of weeds in crops whose stem is not injured by a short exposure to intense heat.
Flame Control
Use of tools, implements and machines
Mechanical Control
Unwanted plants growing in a field competing with the main crop for
nutrients, moisture, and sunlight.
Weeds
Plants injured (i.e. torn leaves, broken stems, and/or
uprooted plant) that may affect crop growth.
Damaged plants
Implement used to remove/destroy the weeds from agricultural
land.
Weeder
The percentage of weeds
removed/destroyed per unit area.
Weeding efficiency or Weeding Index
The percentage of plants injured during the weeding operation
Percent damaged plants
Classification of Weeders: Based on Soil Working Part
- Blade Type
- Tine Type
- Rotary Type
Classification of Weeders: Based on Power Source
- Manual Weeder
- Animal Drawn Weeder
- Tractor-Drawn Weeder
- Power Weeder
Rectangular, triangular and crescent shapes with cutting edges sharpened and hardened for soil cutting and weed uprooting.
Blade type Weeder
Straight or curved, round or square cross-section steel rods sharply pointed and hardened at the soil working end.
Tine type Weeder
Example of Blade Type Weeder
- Rectangular Shape
- Triangular Shape
- Crescent Shape
Example of Tine Type Weeder
- Straight, square tine
- Curved, square tine
Curved spikes or paddles attached radially to a common axle which rotate when pushed forward to uproot and bury weeds.
Rotary type Weeder
Example of Rotary Type Weeder
- Curved Spikes
- Straight Spikes / Puddles
Hand-held or push-type weeders for upland or lowland.
Manual weeders
Utilize the blade and tine type of soil working parts with short (< 0.5 m), medium (< 1m) and long (> 1m) handles.
Hand-held weeders
Utilize any of the three types of soil working parts for upland (wheel hoe) and lowland (rotary weeder) weeding.
Push-type weeders
Soil working parts are mounted on a frame or tool bar pulled by an animal for upland weeding.
Animal-drawn weeders
Soil working parts are mounted on a frame or tool bar pulled by a two-wheel or four-wheel tractor for upland/dry field weeding.
Tractor-drawn weeders
Rotary type weeder driven by its own engine for lowland/wet field weeding.
Power weeders
Size of the Area per Trial: Hand-held
20 sqm
Size of the Area per Trial: Push type
100 sqm
Size of the Area per Trial: Animal-drawn
250 sqm
Size of the Area per Trial: Two-wheel Tractor-drawn
500 sqm
Size of the Area per Trial: Four-Wheel Tractor-Drawn weeders
1,000 sqm
Performance Requirements
- The weeding efficiency shall be at least 80%.
- The percentage of plant damage shall not exceed 6 %.
An operation that requires some kind of tool that will stir the surface of the soil to shallow depth in such a manner that young weeds will be destroyed and crop growth promoted.
Cultivation
Cultivation to control weeds by stirring the soil may start on the prepared seedbed prior to planting, the soil can be cultivated before emergence for some crops.
Cultivating Equipment
Objectives of Cultivation
- Retain moisture by:
a) Killing weeds
b) Loose mulching on surface
c) Retaining rainfall - Develop plant food
- Aerate the soil to allow oxygen to penetrate soil.
- Promote activity of microorganisms
Implement for seedbed preparation, weed eradication, or fallow cultivation subsequent to some form of primary tillage, equipped with spring steel shanks.
Field Cultivator
Classification of Field Cultivators: According to Type of Driving Tractor
- Two wheel tractor driven
- Four wheel tractor driven
Classification of Field Cultivators: According to Type of Mounting
- Rear Mounted
- Front Mounted
Classification of Field Cultivators: According to Type of Shank
- “C”-shaped shank or C-shank
- “S” or “K”-tine shank
Type of field cultivator wherein a two-wheel tractor is used to drive the soil tool.
Two-wheel Tractor Driven
Type of field cultivator wherein a four-wheel tractor is used to drive the soil tool.
Four-wheel Tractor Driven
Type of field cultivator wherein the implement is mounted behind the tractor.
Rear Mounted
Type of field cultivator wherein main frame is mounted far behind the tractor.
Drawn type cultivator
Type of field cultivator wherein main frame is mounted to the rear of the tractor using the three-point hitch linkages.
Three-point hitch mounted
Type of field cultivator wherein main frame is mounted on the front of the tractor.
Front Mounted
The one which atomizes the spray fluid into small droplets and eject it with little force for distributing it properly.
Regulates the amount of pesticide to avoid excessive application that might prove wasteful or harmful.
Sprayers
Most popular way of applying chemicals in the Philippines is with the use of?
Knapsack sprayers
Used primarily for the application of herbicides, insecticides, fungicides and plant nutrients.
Sprayers
Nozzles: Performance is dependent on hydraulic energy as follows
- The higher the pressure, the smaller the droplets
- The higher the pressure, the higher the flow rate
- The higher the pressure, the wider the spray angle
Produces a cone shaped pattern of spray which
could be hollow or solid cone. Best suited for spraying crops because it produces a spray in
which droplets approach the leaves from several angles. The pressure is high and the orifice is
small.
Cone type Nozzle
Produces flat pattern. Best suited for spraying flat surfaces as in the application of herbicides. The pressure is low and the orifice is large.
Fan type Nozzle
This is carried out to determine the ratio of the actual volume of fluid discharge to that of the piston or plunger displacement in one stroke.
Volumetric Efficiency
