Monitoring and Scouting in RiceIntroduction

Agricultural crops are

attacked by a large

number of pest species

including insect pests,

diseases, nematodes and

weeds. For ensuring good

crop productivity effective

management of these

pests becomes extremely

important. Earlier, there

was sole reliance on

pesticides for controlling

pests.

Rice crop damaged by brown planthopper

However, indiscriminate

use of pesticides has

resulted in several

problems related to pest

control and environment.

These include development

of pesticide resistance in

pests, pest resurgences

and outbreaks, death of

bio-control agents, adverse

effects on useful organisms

and harm to human &

animal health and

environment in general.

Pesticide spray on rice crop

Due to these drawbacks of

pesticides, integrated pest

management (IPM) concept

came in to being. The IPM is

an ecological approach to

pest problems where

different control tactics such

as cultural, mechanical,

physical, resistant

behavioural, biological and

chemical methods are

integrated for suppression of

pest populations.

Monitoring is backbone of

IPM. Farmer must keep

continuous vigil of pest

activity on crops.

IPM

DB-Cultural methods

DB-Mechanical Methods

DB-Physical methods

DB-Bio-control methods

DB-Chemical methods

Multipest-modules

Dissemination

insect Disease

nematode weeds

ETL

Multiple pest management programmesConcept of Integrated pest management

Information on activity of pests

is indispensible in pest

management. Pest monitoring

refers to regular observations on

pest activity throughout the crop

season. It is also be known as

surveillance or regular survey. It

helps in issuing forewarning and

facilitates proper timing of plant

protection measures thereby

preventing avoidable losses and

environmental contamination,

and ensuring favourable benefit-

cost.

Pest Monitoring in Rice

Monitoring of rice pests

A timely executed treatment very well

substitutes for 3-4 ill-timed

application.

Monitoring also provides information

on important pests as well a their

natural enemies of pests and their

density relationships.

Natural enemy- spider

Brown planthopper

Likewise, monitoring data

can also be used to analyze

relation between pest

population and physical

factors, which can then be

used for pest forecasting.

As quantification of pest

problems is time and labour

intensive activity,

monitoring technique

should be very efficient. It

should provide

representative picture of

pest situation in reasonable

amount of time.

Diseased rice plant

Pest monitoring procedureA. Detailed observations on

crop

For pest monitoring and to

assess bio control, field

observations should be

recorded regularly.

Select randomly five fixed

observation plots of one acre

each in an area.

In each of the plots,

thoroughly examine 25 hills by

randomly selecting five hills at

five places.

The hills should be selected by

moving diagonally or in a zig-

zag manner in the field. White-ear damage due to stem borer

Stem borer larvaStem borer adult

The observation

should be recorded

at 10-day interval

from sowing to mid

tillering and weekly

intervals after mid-

tillering stage.

Pest should be

searched on

relevant plant part.

In case of brown

planthopper, plant

stems should be

inspected and not

the leaves.

Monitoring brown planthopper on rice

Pest wise observationsStem borer: Total number of tillers and dead

hearts on 25 hills during vegetative phase, and total number of reproductive tillers and white-ears during reproductive phase is enumerated to find per cent incidence.

Gall midge: Total number of tillers and silver

shoots is enumerated and per cent incident is determined.

Leaf folder, hispa and whorl maggot: Total number of leaves and a damaged leaves is counted and per cent leaf damage is calculated.

Planthoppers: Total nymphal and adult population is counted.

Gundhi bug: Number of bugs is counted.

Leaf folder

Rice gundhi bug

Hispa

B. Roving survey: For pest monitoring in large area in short time, roving pest surveys on pre-determined routes can be conducted at every 10-day interval regularly and observations are recorded at every 5-10 km distance depending upon the distance of route to be covered. Everyday at least 20 spots should be observed.

C. Sweep nets and water pans may also be used to assess population of insect pests and bio-control agents.

D. Light traps such as Chinsurah type or any other light trap with 200 watt mercury lamp can also be operated for two hours in the evening to observe phototactic insects.

E. Pheromone traps @ 5 traps per hectare may be used to monitor yellow stem borer population.

Light trap

Pheromone trap

Precautions during monitoring

Make sure that you are properly

equipped with the tools you may

need once in the field.

Identify the field by the farmer’s

name, field number and location with

GPS.

Record date and time and weather

conditions.

Record general soil, and crop growth

stage and condition.

Sample the field in the pattern

prescribed for particular pest.

If needed, collect pest samples or

their damage for later identification.

Also record natural enemies of pests.

Report the results of monitoring.

Discussion on pest problems with farmers

Let’s Sum upPest monitoring refers to regular observations on pest activity throughout the crop season.

Monitoring is backbone of IPM. Farmer must keep continuous vigil on pest activity on crops.

Monitoring helps in issuing forewarning and facilitates proper timing of plant protection measures thereby preventing avoidable losses and environmental contamination, and ensuring favourable benefit-cost.

Monitoring also provides information on important pests as well a their natural enemies.

Monitoring technique should be very efficient. It should provide representative picture of pest situation in reasonable amount of time.

Roving survey refers to pest monitoring in large area in short time on pre-determined route.

Sweep nets, water pan traps, yellow sticky traps, light traps and pheromone traps are also used for pest monitoring.