Your School's Whatsapp Group - Join Us now
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now

1991 WAEC Agricultural Science Theory Describe briefly the side effects of preventive and control measures of method diseases and pests...

Agricultural Science
WAEC 1991

Describe briefly the side effects of preventive and control measures of method diseases and pests of crops under the following headings: (a) chemical control (b) biological control (c) cultural of control .

WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
Explanation

The side effects of various preventive and control measures of diseases and pests of crops are:

(a) Chemical method of control:

(i) Almost all the chemicals used are toxic to man and domestic animals.

(ii) Some beneficial insects of soil organisms may be destroyed.

(iii) Pests and diseases may develop resistance to chemical. (iv) Some chemicals may cause water pollution.

(v) Empty containers could be a source of poison when used as containers for consumables.

(b) Biological method of control:

(i) The new organisms introduced may start attacking crops which were formerly free from attack.

(ii) The predators introduced may feed on other beneficial insects causing imbalance in the ecosystem.

(c) Cultural method of control:

(i) The use of fire may spread to other farms

(ii) The use of fire may kill some beneficial organisms.

(iii) It can lead to destruction and losses of organic matter in the soil.

(iv) It can also destroy the soil structure


Report an Error Ask A Question Download App
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Your School's Whatsapp Group - Join Us now
Post UTME Past Questions Agent

Contributions ({{ comment_count }})

Please wait...

{{ settings.no_comment_msg ? settings.no_comment_msg : 'There are no comments' }}

Quick Questions

Post your Contribution

Please don't post or ask to join a "Group" or "Whatsapp Group" as a comment. It will be deleted. To join or start a group, please click here

{{ quote.posted_by.display_name }}
{{ settings.form_textarea_description }}
 
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
Post UTME Past Questions Agent
Your School's Whatsapp Group - Join Us now
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Post UTME Past Questions Agent
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Your School's Whatsapp Group - Join Us now
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts