Agricultural Botany and Weed Science — DU B.Sc. (Hons.) Botany Previous Year Question Papers

5. (a)Discuss the advantages of integrated pest management. (5) (b) What is biofertilizer? Explain its importance. (c) Discuss the role of light on the germination of seeds. (5) Weed Science Generic Elective 2. Attempt four questions in all including Question No. 3. All Parts of a questions to be attempted together. 4. Draw diagrams wherever required. 1. (a) Define (any five): (iii) Disease triangle (vi) Seed dormancy (b) Write one word for the following (any five) : (i) A growth hormone that stimulates germination of seed. (ii) The response of plant to the period of day/ (iii) The process in which the shoot apex of a plant grows faster and prevent the growth of lateral buds. (iv) A unwanted plant that inhibits the growth of desirable plants in a field. (v) A gaseous plant hormone. (vi) Example of a long day plant. 2. Write short note on (any three) : (5x3=15) (a) Invasive plants (b) Seed vigour (d) Physiology of fruit ripening 3. Differentiate between the following (any five) : (i) Short day and Long day plant (ii) Stratification and Scarification (iii) Growth promoters and Growth retardants (iv) Pr and Pfr (v) Biological and Chemical control of weeds (vi) Epigeal and Hypogeal seed germination 4. (a) Give the chemical nature-, discovery and physiological effects of cytokinin. (9) (b) Discuss the mechanism of senescence in detail.