Theory question 105
Crop Propagation(a)(i) Define vegetative propagation. (ii) Give three advantages and three disadvantages of vegetative propagation.
(b) State four cultural methods used for controlling crop pests in the field.
(c) Enumerate four harmful effects of chemical pest control.
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(a)(i) Raising new plants from parts of the parent other than seed, e.g. stems, roots, leaves, suckers, tubers.
(ii) Advantages: offspring are true to type; plants mature and fruit earlier; useful for plants that produce no viable seed; desirable traits easily kept. Disadvantages: diseases carried over from the parent; materials are bulky and perish quickly; no new varieties arise; costly to transport and store.
(b) Any four: crop rotation; early planting/harvesting; clean weeding/field sanitation; destroying crop residues; use of resistant varieties; trap cropping; proper spacing; mixed cropping.
(c) Any four: poison humans and animals; residues in food; kill beneficial insects and natural enemies; pollute soil and water; pests develop resistance; high cost; scorching of crops if overdosed.
Vegetative propagation advantages and disadvantages should not repeat each other.