WAEC Agricultural Science questions

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

1. Question 241· Soil fertility, manures and fertilisers· WAEC

   Organic manure includes

   • Afarmyard manure
   • Burea
   • CNPK
   • Dammonium sulphate

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2. Question 242· Soil fertility, manures and fertilisers· WAEC

   Farmyard manure improves soil by

   • Amaking it saline
   • Badding nutrients and improving structure
   • Ckilling earthworms
   • Dincreasing erosion

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3. Question 243· Soil fertility, manures and fertilisers· WAEC

   Green manure is

   • Agreen plants ploughed into the soil while still fresh
   • Banimal dung
   • Ca chemical fertiliser
   • Dcompost made from refuse

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4. Question 244· Soil fertility, manures and fertilisers· WAEC

   Soil fertility is reduced by

   • Acrop rotation
   • Bcontinuous cropping without fertiliser
   • Cmanuring
   • Dfallowing

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5. Question 245· Soil fertility, manures and fertilisers· WAEC

   The bacteria in the root nodules of legumes that fix nitrogen belong to the genus

   • AClostridium
   • BNitrosomonas
   • CRhizobium
   • DPseudomonas

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6. Question 246· Soil fertility, manures and fertilisers· WAEC

   Crop rotation helps to maintain soil fertility by

   • Agrowing one crop every year
   • Bgrowing crops with different nutrient needs in sequence
   • Cburning the farm
   • Dremoving all residues

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7. Question 247· Soil fertility, manures and fertilisers· WAEC

   Leaching reduces soil fertility by

   • Aincreasing organic matter
   • Badding nutrients
   • Cwashing nutrients down beyond the reach of roots
   • Dimproving soil structure

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8. Question 248· Soil fertility, manures and fertilisers· WAEC

   Which practice helps to maintain soil fertility?

   • Abush burning
   • Bcontinuous cropping of maize
   • Ccrop rotation that includes legumes
   • Dovergrazing

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9. Question 249· Soil fertility, manures and fertilisers· WAEC

   A farmer applies 100 kg of NPK 15-15-15 fertiliser. How much nitrogen does it supply?

   • A5 kg
   • B45 kg
   • C100 kg
   • D15 kg

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10. Question 250· Soil fertility, manures and fertilisers· WAEC

    Adding lime to an acidic soil raises its

    • Aorganic matter
    • Bsalt content
    • CpH
    • Dnitrogen content

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11. Question 251· Soil fertility, manures and fertilisers· WAEC

    Muriate of potash supplies

    • Apotassium
    • Bnitrogen
    • Cphosphorus
    • Dsulphur

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12. Question 252· Soil fertility, manures and fertilisers· WAEC

    Yellowing of older leaves (chlorosis) is a sign of

    • Atoo much sunlight
    • Bexcess water only
    • Cnitrogen deficiency
    • Dphosphorus excess

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13. Question 253· Soil fertility, manures and fertilisers· WAEC

    Phosphorus deficiency in crops shows mainly as

    • Apoor root growth and purplish leaves
    • Byellowing of older leaves
    • Cscorched leaf margins
    • Dwhite spots on fruits

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14. Question 254· Soil fertility, manures and fertilisers· WAEC

    NPK 15-15-15 contains

    • Aequal proportions of nitrogen, phosphorus and potassium
    • B15 kg of each nutrient
    • Conly nitrogen
    • Dno potassium

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15. Question 255· Soil fertility, manures and fertilisers· WAEC

    Nitrogen in fertilisers helps plants to

    • Aripen fruits only
    • Bform roots only
    • Cproduce healthy green leaves
    • Dresist drought only

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16. Question 256· Soil formation and properties· WAEC

    In a soil profile, the top layer rich in humus is the

    • AB horizon
    • BA horizon
    • CC horizon
    • Dbedrock

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17. Question 257· Soil formation and properties· WAEC

    Which soil type has the largest particles?

    • Asandy soil
    • Bclay soil
    • Cloamy soil
    • Dsilty soil

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18. Question 258· Soil formation and properties· WAEC

    Which rock type forms from cooled magma and weathers to give the parent material of many soils?

    • Ametamorphic rock only
    • Bsedimentary rock only
    • Cigneous rock
    • Dorganic rock

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19. Question 259· Soil formation and properties· WAEC

    Soil texture can be estimated in the field by

    • Atasting it
    • Brubbing moist soil between the fingers
    • Cburning it
    • Dweighing it on a balance only

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20. Question 260· Soil formation and properties· WAEC

    A soil with a pH of 4.5 is

    • Asaline
    • Bneutral
    • Calkaline
    • Dstrongly acidic

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