Grade 10 Agriculture – Growing Selected Crop Quiz

1. When growing maize in Kenya, which practice helps ensure good germination and uniform crop stand?

Planting very deep seeds to reach moisture
Broadcasting seeds randomly without measuring depth
Planting seeds at the recommended depth and spacing
Using more seeds than recommended in each hole
Explanation:

Planting maize at the recommended depth (about 2–5 cm depending on soil moisture) and spacing ensures good germination, uniform growth and makes management like weeding and fertilising easier.

2. What is the best time to plant beans in most parts of Kenya for a reliable rainfed crop?

During the dry season without irrigation
At the end of the rainy season
At the start of the rainy season
In the coldest month of the year
Explanation:

Planting beans at the start of the rains takes advantage of soil moisture for germination and early growth; planting too early or late risks poor establishment or drought stress.

3. Which seed characteristic is most important when selecting potato seed tubers for planting?

Very large tubers with visible scab
Healthy, disease-free tubers of recommended size
Tubers from unknown sources without certification
Old stored tubers sprouting long weak shoots
Explanation:

Using healthy, certified seed tubers of the recommended size reduces disease introduction, ensures vigorous growth and improves yield; diseased or old tubers reduce crop performance.

4. Which practice helps control maize stem borers in smallholder Kenyan farms?

Avoiding field hygiene to maintain biodiversity
Planting only one crop without crop rotation
Ignoring pests until harvest
Early planting and frequent scouting with timely removal of infested stems
Explanation:

Early planting can escape peak pest pressure and regular scouting allows farmers to remove borer-infested stems or apply control measures early, reducing damage.

5. For tomato production in Kenya, which soil condition is best for healthy plants?

Compacted soils with poor aeration
Very sandy soils with no nutrients
Waterlogged soils that hold water for long
Well-drained fertile soil with good organic matter
Explanation:

Tomatoes require well-drained, fertile soils rich in organic matter to support root growth and reduce disease; waterlogged or compacted soils cause root problems and low yields.

6. What is an appropriate spacing for Irish potato planting to balance tuber size and yield?

30–40 cm between plants in rows 60–75 cm apart
5 cm between plants in rows 10 cm apart
Planting seeds closely without rows
2 m between plants in rows 3 m apart
Explanation:

Spacing potatoes 30–40 cm within rows and 60–75 cm between rows gives roots room to develop and allows cultivation and hilling, which improves tuber size and overall yield.

7. Which fertilizer practice is recommended for maize to improve yields in Kenyan smallholdings?

Applying fertilizer randomly without following rates
Applying all fertilizer once after harvest
Using only organic manure without considering fertilizer rates
Applying basal nitrogen and top-dressing with urea at knee height
Explanation:

Applying part of the nitrogen as basal and top-dressing at knee height (about 4–6 weeks) matches crop demand and improves efficiency and yields versus a single mis-timed application.

8. Which method helps conserve soil moisture for crops during dry spells in Kenya?

Mulching with crop residues or grass
Leaving soil bare and exposed
Burning residues to clear fields
Frequent deep tilling during the dry period
Explanation:

Mulching reduces evaporation, moderates soil temperature and adds organic matter, helping conserve moisture and improve plant growth during dry spells.

9. When is the correct time to harvest maize for consumption to reduce losses in storage?

When grain moisture is about 13–15% and husks are dry
Only after the next rainy season
When cobs are still green and soft
Immediately after flowering
Explanation:

Harvesting maize when grain moisture is around 13–15% and husks are dry reduces post-harvest losses from mold and pests and improves storage quality.

10. What simple practice reduces soil erosion on Kenyan sloping farms growing crops like maize or beans?

Planting contour lines or terraces and maintaining grass strips
Channeling runoff to neighbouring farms
Clearing all vegetation including grass strips
Ploughing straight down the slope
Explanation:

Contour planting, terraces and grass strips slow runoff, reduce erosion and protect soil fertility on slopesβ€”important for sustainable crop production.

11. Which weed control method is suitable for small-scale vegetable gardens in Kenya?

Allowing weeds to grow alongside the vegetables
Using no control and hoping for competition to balance
Hand weeding regularly and removing weeds before seeding
Applying chemicals without following instructions
Explanation:

Regular hand weeding, especially early, reduces competition for nutrients, water and light in small gardens and is safe and effective when done correctly.

12. For successful coffee growing on small Kenyan farms, which factor is most important?

Planting coffee only on steep bare slopes
Growing coffee in open full sun without shade
Shade management to protect coffee from intense sun
Waterlogging the soil to retain moisture
Explanation:

Coffee in Kenya often does well with managed shade to reduce heat stress, conserve moisture and maintain quality; full sun or waterlogged conditions harm coffee.

13. Which practice helps reduce post-harvest losses of Irish potatoes for smallholders?

Storing tubers in damp, dark pits on the ground
Storing potatoes in plastic bags immediately after harvest
Leaving tubers in the field to dry in the sun for weeks
Curing tubers in a cool, shaded, well-ventilated place before storage
Explanation:

Curing helps heal wounds and reduces rot; storing in cool, ventilated, shaded conditions prevents sprouting and rotting, reducing losses.

14. What is the benefit of crop rotation when growing maize and legumes in Kenyan farms?

It increases the build-up of crop-specific pests
It prevents legumes from fixing nitrogen
It removes all nutrients from the soil
It reduces pest and disease build-up and improves soil fertility
Explanation:

Rotating maize with legumes breaks pest and disease cycles and legumes fix nitrogen, improving soil fertility and subsequent crop yields.

15. Which irrigation method is most water-efficient for vegetable plots in Kenya?

Overhead irrigation during the hottest mid-day hours
Spraying water randomly without timing
Flooding the whole field frequently
Drip irrigation delivering water to the root zone
Explanation:

Drip irrigation applies water directly to roots with minimal evaporation and runoff, making it more efficient and suitable for smallholder vegetable production.

16. Which is a recommended control method for maize weeds in the early growth stage?

Timely hand hoeing or inter-row cultivation
Placing weeds around the plants as mulch
Waiting until the crop matures before weeding
Applying fertilizer to encourage crop over weeds
Explanation:

Early hand hoeing or inter-row cultivation removes weeds before they compete strongly with the crop, improving yields and making later management easier.

17. When preparing land for sunflower planting in Kenya, what should a farmer do first?

Plant immediately without any land preparation
Clear the field, plough, and create a fine tilth suitable for sowing
Burn all residues leaving soil bare
Flood the field and compact the soil
Explanation:

Proper land preparation (clearing, ploughing, making a fine seedbed) ensures good seed-soil contact, uniform germination and reduces early weed competition.

18. Which sign indicates that maize plants might be deficient in nitrogen?

Purple spots only on the husk
Excessively dark green leaves and stunted roots
Yellowing of older leaves starting from the base
Flowers forming earlier than usual
Explanation:

Nitrogen deficiency typically causes older leaves to turn pale or yellow first because N is mobile and moves to new growth; this reduces overall crop vigour and yield.

19. For small-scale tomato farmers, which pest control is appropriate and safe?

Spraying any available household chemical without guidance
Integrated use of cultural practices, resistant varieties and approved pesticides when necessary
Planting only in swampy, waterlogged areas
Never removing infected plants and ignoring pest signs
Explanation:

Integrated pest management combining good cultural practices, resistant varieties and careful pesticide use reduces pest damage safely and sustainably.

20. Which planting practice improves bean yields by reducing disease spread?

Planting in the same spot every season without rest
Saving seed from diseased plants to increase genetic diversity
Using certified seed and avoiding planting seed from diseased plants
Mixing bean seed with maize seed when planting
Explanation:

Certified seed is disease-free and using clean seed reduces disease introduction and spread, improving germination and yields.

21. When growing onions, what is a key practice to achieve good bulb size?

Crowding seedlings close together to save space
Maintaining recommended plant spacing and timely thinning
Harvesting before bulbs form
Watering only once at planting and never again
Explanation:

Proper spacing and thinning reduce competition for light and nutrients, allowing bulbs to develop full size and improving overall yield.

22. What is the advantage of using improved drought-tolerant maize varieties in arid parts of Kenya?

They can be planted anytime without consideration of rainfall
They perform better under low rainfall and reduce crop failure risk
They always give the highest yield regardless of conditions
They require no fertilizer or management
Explanation:

Drought-tolerant varieties are bred to cope with limited water and can give more stable yields in dry areas, though good management still matters.

23. Which simple measure reduces post-harvest loss of maize due to weevils in Kenyan households?

Mixing harvested grain with soil to deter pests
Storing damp maize in sacks on the floor
Drying maize properly and storing in clean, dry containers off the ground
Keeping harvested maize in the field for months
Explanation:

Proper drying reduces moisture that allows pests and molds; clean, elevated storage containers reduce weevil access and extend grain shelf life.

24. Which soil test result should a farmer consider before applying phosphorus fertiliser for crops like maize and beans?

Low available phosphorus levels in the soil test
High soil phosphorus, indicating no need for more
Ignoring the soil test and applying more phosphorus always
Soil pH only without nutrient levels
Explanation:

Applying phosphorus when the soil test shows low available P addresses nutrient deficiency efficiently; unnecessary application wastes resources and can harm the environment.

25. Which practice helps increase yields when planting sweet potatoes on a small Kenyan farm?

Planting only in shaded, compacted areas
Using rotten vine cuttings saved from previous harvest
Using healthy vine cuttings and planting on ridges with good spacing
Planting vine cuttings too close in wet pits
Explanation:

Healthy vine cuttings, ridging for loose soil, and proper spacing promote root development and reduce disease, leading to better sweet potato yields.

26. Which action helps prevent soil nutrient loss when growing crops continuously?

Harvesting without considering soil health
Removing all crop residues and never adding fertiliser
Planting the same crop without replenishing nutrients
Applying organic manure and practising crop rotation
Explanation:

Adding organic manure returns nutrients and improves soil structure, while rotation with legumes helps restore soil nitrogen, sustaining long-term productivity.