Question

What are weedicides? Give their effect on the ecology of a place.

Answer 1

Hint: Weed are plants which are generally considered as undesirable or a plant in a wrong place. They are generally removed as they utilise the nutrients which were originally meant for the plant of interest.

Complete Answer:
As we already know they are undesirable plants which grow along with crops. The weeds generally feed on the nutrients which are to be provided to the crops, thereby reducing the amount of nutrition that the plant gets. They also compete for water, sunlight, minerals, etc , thereby hindering the growth of the crop.

Weedicides are the chemicals which are generally sprayed all around the field to prevent the growth of weeds. An example of common weedicide is 2,4- D (2,4 dichlorophenoxy acetic acid) which acts as a dicot weedicide.

As these weedicides have an advantage, there are various negative ways by which they affect the ecology of a place,
- They can have role in sex reversal of certain organisms which has temperature dependent sex ratios, thereby causing an alternation in natural sex ratios.
- The frog populations are impacted negatively by the presence of weedicides.
- They also impact negatively on bird population.
- Long term weedicides can also lead to various types of cancer.

Note: Weeding is the process by which weeds are removed. Various weeding methods include,
- Manual method- In this method, the weed is removed manually by hand from the farm.
- The manual method is also done with the help of a khurpi.
- Tiling before sowing also helps in preventing the growth of weeds.