Auxins as Herbicides: 2,4-D Selectivity — NEET Biology
✅ Asked in NEET 2024Auxins also induce parthenocarpy, e.g., in tomatoes. They are widely used as herbicides. 2, 4-D, widely used to kill dicotyledonous weeds, does not affect mature monocotyledonous plants. It is used to prepare weed-free lawns by gardeners. Auxin also controls xylem differentiation and helps in cell division.
NTA tests whether students understand that 2,4-D is a selective herbicide that kills dicots but NOT mature monocots—this selectivity is the key concept. Students commonly mistake this by thinking 2,4-D kills all plants equally or confuse which plant type it affects. The trap: they may memorize "2,4-D kills weeds" without remembering the critical word "dicotyledonous." To get it right, remember that monocots (grasses) have different auxin sensitivity and developmental patterns, making them resistant to 2,4-D at maturity. This selectivity is why 2,4-D creates weed-free lawns—it removes dicot weeds while preserving monocot grass.
This paragraph was tested 2 times in NEET.
Auxin is used by gardeners to prepare weed-free lawns. But no damage is caused to grass as auxin (NEET 2024)
The plant hormone used to destroy weeds in a field is: (NEET 2021)
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