NEETBotanyPlant - Growth and Development
A gardener sprays the plant growth regulator 2,4 -D on a lawn that contains a mixture of mature grasses and broad-leaved weeds. What will be the specific outcome of this application?
Options
- AIt will kill the mature grasses and leave the broad-leaved weeds unaffected.
- BIt will kill the broad-leaved weeds while leaving the mature grasses unaffected.
- CIt will act as a non-selective herbicide and kill both the grasses and the broad-leaved weeds.
- DIt will promote the rapid vegetative growth of both the grasses and the broad-leaved weeds.
Correct answer
B. It will kill the broad-leaved weeds while leaving the mature grasses unaffected.
Step-by-step solution
According to NCERT, 2,4 -D ( 2,4 -dichlorophenoxyacetic acid) is a synthetic auxin widely used as a weedicide. It selectively kills dicotyledonous (broad-leaved) weeds but does not affect mature monocotyledonous plants (such as grasses). Therefore, the broad-leaved weeds will be destroyed, allowing the gardener to maintain a weed-free lawn, while the mature grasses will remain unaffected. Answer: It will kill the broad-leaved weeds while leaving the mature grasses unaffected.