Theory question 104
Crop Diseases(a) Explain the term land tenure system.
(b) Define the term weed.
(c) Discuss groundnut rosette diseases under the following headings: (i) causal organism; (ii) mode of transmission; (iii) two symptoms; (iv) two control measures.
(d) State four characteristics of each of the following factors of production (i) land; (ii) capital.
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(a) Land tenure system is the way land is owned, acquired, used and transferred by individuals, families, communities or government.
(b) A weed is any plant growing where it is not wanted (out of place).
(c)(i) A virus (groundnut rosette virus).
(ii) Spread by aphids (Aphis craccivora).
(iii) Any two: stunted, bushy plants; small, crinkled, yellow or mottled leaves; few or no pods.
(iv) Any two: resistant varieties; early and close planting; control aphids with insecticides; uproot and burn infected plants; crop rotation.
(d)(i) Land (any four): a free gift of nature; fixed in supply; immobile; varies in fertility and location; subject to diminishing returns; its reward is rent.
(ii) Capital (any four): man-made; depreciates with use; mobile; can be increased by saving; its reward is interest; its supply depends on savings.
Name the aphid vector for the rosette virus.