Q. Farmers in a particular region were concerned that pre-mature yellowing of leaves of a pulse crop might cause decrease in the yield. Which treatment could be most beneficial to obtain maximum seed yield ?
A) Frequent irrigation of the crop
B) Treatment of the plants with cytokinins along with a small dose of nitrogenous fertilizer
C) Removal of all yellow leaves and spraying the remaining green leaves with 2, 4, 5-trichlorophenoxy acetic acid
D) Application of iron and magnesium to promote synthesis of chlorophyll
Explanation
[Solution from source] Cytokinins delay leaf senescence by keeping chlorophyll and protein from breaking down, and a small dose of nitrogen supports this, so leaves stay green and photosynthesise longer for seed filling. Iron and magnesium help chlorophyll synthesis but do not stop natural senescence-type yellowing. Answer (2).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.