JAMB Agricultural Science questions

306 questions with answers and explanations. Tap an option to check yourself.

1. Question 181· Husbandry of field crops· JAMB

   Thinning in crop production is done to

   • Aincrease the number of plants
   • Bcontrol all pests
   • Creduce competition among seedlings
   • Dharvest the crop early

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2. Question 182· Husbandry of field crops· JAMB

   Cassava stems for planting should be cut about

   • Awithout nodes
   • B2 cm long
   • C2 m long
   • D20-25 cm long with several nodes

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3. Question 183· Husbandry of field crops· JAMB

   The main benefit of mulching a crop is that it

   • Aattracts pests
   • Bincreases soil acidity
   • Cconserves soil moisture
   • Dspeeds up erosion

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4. Question 184· Husbandry of field crops· JAMB

   Earthing up in groundnut and potato production means

   • Aremoving soil from the roots
   • Bheaping soil round the base of the plants
   • Cspraying the leaves
   • Dharvesting early

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5. Question 185· Husbandry of field crops· JAMB

   Nursery beds are usually shaded in order to

   • Akeep rats away
   • Bprotect young seedlings from strong sun and heavy rain
   • Cincrease the light reaching seedlings
   • Draise the soil temperature

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6. Question 186· Husbandry of field crops· JAMB

   Pruning of cocoa trees helps to

   • Areduce yield
   • Bincrease weeds
   • Cremove diseased branches and improve air flow
   • Dattract pests

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7. Question 187· Husbandry of field crops· JAMB

   Ridging land before planting yam mainly helps to

   • Aharden the soil
   • Bkill all pests
   • Creduce sunlight
   • Dloosen the soil for tuber expansion and improve drainage

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8. Question 188· Husbandry of field crops· JAMB

   In most parts of southern Nigeria, maize is best planted

   • Aat the beginning of the rainy season
   • Bin the middle of the dry season
   • Cduring the harmattan
   • Dat the end of the rainy season only

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9. Question 189· Husbandry of field crops· JAMB

   Maize planted at a spacing of 75 cm × 25 cm, one plant per stand, gives a plant population per hectare of about

   • A40,000
   • B53,333
   • C26,667
   • D80,000

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10. Question 190· Husbandry of field crops· JAMB

    The recommended spacing for maize is about

    • A3 m × 3 m
    • B5 cm × 5 cm
    • C75 cm × 25 cm
    • D10 m × 10 m

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11. Question 191· Irrigation and drainage· JAMB

    Infiltration is the

    • Aentry of water into the soil surface
    • Bloss of water from leaves
    • Cflow of water over the surface
    • Dstorage of water in dams

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12. Question 192· Irrigation and drainage· JAMB

    Overhead irrigation can encourage

    • Asalt build-up only
    • Bleaf diseases because the foliage stays wet
    • Cdrought
    • Dsoil acidity

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13. Question 193· Irrigation and drainage· JAMB

    Basin irrigation is suitable for crops such as

    • Arice
    • Bcassava on ridges
    • Cyam on mounds
    • Dgroundnut on heaps

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14. Question 194· Irrigation and drainage· JAMB

    Sprinkler irrigation sprays water

    • Alike rain over the crop
    • Bonly on the roots
    • Cin channels
    • Dby flooding

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    Explanation and discussion

15. Question 195· Irrigation and drainage· JAMB

    The method of irrigation in which water drips slowly at the base of each plant through small pipes is

    • Aflood irrigation
    • Bfurrow irrigation
    • Cdrip irrigation
    • Dsprinkler irrigation

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16. Question 196· Irrigation and drainage· JAMB

    Drip irrigation is suitable where

    • Awater is plentiful everywhere
    • Bwater is scarce
    • Csoil is waterlogged
    • Dthere is no crop

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17. Question 197· Irrigation and drainage· JAMB

    Tile drainage removes excess water through

    • Aplants
    • Bopen channels
    • Cpumps only
    • Dunderground pipes

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18. Question 198· Irrigation and drainage· JAMB

    Furrow irrigation is the method in which water

    • Adrips at the base of each plant
    • Bis sprayed into the air
    • Cflows along channels between crop rows
    • Dis poured by hand from cans

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19. Question 199· Irrigation and drainage· JAMB

    A disadvantage of sprinkler irrigation is that it

    • Acannot be used on slopes
    • Bneeds no pumping
    • Calways causes erosion
    • Dloses much water through evaporation and is costly

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20. Question 200· Irrigation and drainage· JAMB

    Surface drainage removes

    • Aall soil
    • Bnutrients
    • Cpests
    • Dexcess water from the soil surface

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    Explanation and discussion