AGRICULTURE PAPER 1 Marking Scheme - 2019 KCSE Prediction Answers Set 2

1. Because it involves experimentation and application of scientific knowledge (1 x 1 = 1mks)
2.  
   • Shifting cultivation
   • Nomadic pastrolism
   • Agroforestry
   • Organic farming
   • Mixed farming
   • Ranching               (Any 4 x ½ =2mks)
3. Soil structure is the physical appearance of soil according to the way individual soil particles are arranged /packed/aggregated while soil texture is the relative proportion of various sizes of the minerals particles of the soil (1 x 1 = 1mks) Mark as whole
4.  
   • To increase soil aeration
   • To increase soil volume
   • To raise soil temperature
   • To increase microbial activities
   • To reduce soil erosion
   • To get rid of toxic substances that may be disastrous to good crop performance (Any 4 x ½ =2mks)
5.  
   • Lowers the level of water in the Dam and reservoirs
   • Decline in fish production ( 2x ½ =1mk)
6.  
   • It encourages early establishment of crop pasture  
   • Saves on the use of commercial fertilizers
   • There is intensive use of land i.e it promoted intercropping /Efficient land use
   • Controls soil erosion due to efficient ground cover (Any 3 x ½ =1½mks)
7.  
   • It encourages seed germination
   • Promotes microbial activities
   • Improves quality of crop produce
   • Enhances vigorous growth and development
   • Enhances high yields
   • Minimises incidences of certain pests and diseases (Any 4 x ½ =2mks)
8.  
   1. Suckers  
   2. Suckers/slips/crowns
   3. Stemtubers
   4. Splits (Any 4 x ½ =2mks
9.  
   • Reduces land disputes
   • It acts as security of land ownership
   • Can be used as security for loan
   • Encourages farmers to carry out long term investment on land (4 x ½ =2mks)
10.  
    • Crop rotation – Growing of crops of different families on the same piece of land in an orderly sequence (1mks)
    • Mulching – covering of ground around a growing crop with organic material or artificial sheets                            (1mks)
11.  
    • Seed impurity
    • Low – germination percentage
    • Close spacing
    • More seeds per hole / Broadcasting
    • Early planting /Dry Planting (Any 4 x ½ =2mks)

12. Role of Nitrogen
    • Constituent of chlorophyll
    • Promoted crop vegetative growth
    • Protein synthesis
    • Regulates availability of phosphorous and potassium in the soil
    • Improves the quality of leafy crops (Any 3 x ½ =1½mks)
13.  
    • Training
    • Giving incentives /improving terms and conditions
    • Farm mechanization
    • Labour supervision
    • Proper payment / Renumeration
    • Assigning tasks or duties according to skills (Any 4 x ½ =2mks)
14.  
    • To raise the PH of the soil
    • To improve fertility of soil
    • To improve the structure of the soil
    • To improve the process of nodulation in Legumes    (4 x ½ =2mks)
15.  
    • Organic mulch
    • Crop residue /animal remains
    • Green manure
    • Farm yard manure
    • Compost manure (Any 3 x ½ =1 ½ mks)
16.  
    • Drying
    • Threshing /shelling
    • Winnowing
    • Dusting
    • Sorting out
    • Packaging
    • Processing  ( Any 4 x ½ =2mks)
17.  
    • Plants morphology and anatomy
    • Stage of plant growth
    • Weather conditions
    • Formulation
    • Concentration
    • Method of application
    • Type of weeds
    • Weed metabolic factors  (Any 3 x ½ =1½ mks)
18. Act of deciding on how to allocate available scarce resource to alternative uses based on farmer’s interest ( 1 x 1=1 mk)

SECTION B (60MKS)

19.  
    1. Blossom End Rot ( 1 x 1=1 mk)
    2.  
       • Irregular application of water /water stress;
       • Excessive application of Nitrogen in early stages
       • Deficiency of calcium – reject lack of calcium (3 x 1 =1 mks)
20.  
    1. Army worm ( 1 x 1=1 mk)
    2. Mode of feeding – Biting & chewing (1 x 1=1 mk
    3.  
       • Damage the leaves thus reducing Photosynthesis area
       • Damage the stem thus interfering with transport system
       • Injure and cause wound on plants exposing them to secondary infection (3 x 1 = 3mks)
21.  
    1. Ridging ( 1 mk)
    2.  
       • Dig soil in a continuous lines
       • Soil is heaped on one side for form a ridge and a furrow                                               ( 2mks)
    3. Advantages
       • Enhances expansion of tubers
       • Makes harvesting of root crops easy
       • Prevents soil erosion
       • Conserves soil moisture (Any 2 x 1=2 mk)
22.  
    1. Per capita income = ^{Gross Domestic product}/_Population
       Country A = ¹⁸⁰⁰/₃₆ = 50
       Country B = ¹²⁰⁰/₁₅ = 80 (3mks)
    2. Country B is more developed     (1mk)
    3. Has higher per capita income (1mk)
    4. By creating employment , developing industries , increasing production. (Any 2 x 1=2 mk)

SECTION C (40mks)

23.  
    1.  
       1. Selection and preparation of planting materials
          • Beans are established from seed
          • Select seeds to discard damaged and wrinkled ones
          • Dress seeds with appropriate chemical to control soil borne pests .
          • Innoculate seeds with right strain of Rhizombium bacteria ( Any 3 x 1 = 3mks)
       2. Planting
          • Plant at the onset of rain
          • Plant 2 -3 seeds per hole at a spacing of 30-45 cm by 15cm
          • Apply DAP fertilizer during planting
          • Plant at the depth of 4cm ( Any 3 x 1 = 3mks)
       3. Disease control
          • control haloblight by rogueing , crop rotation and spraying with appropriate fungicide
          • Control bean anthracnose by spraying with appropriate fungicide planting resistant varieties (Any 2 x 1 = 2mks)
    2.  
       • Soil type
       • Soil moisture content
       • Type of germination
       • Size of seeds (Any 4 x 1 = 4mks)
    3. Advantages of mixed grass legume mixture Over pure grass
       • Its more paratable
       • Farmers has security against total loss due to attack by pests, diseases or bad weather
       • Mixed pasture yields more per unit area than pure grass pasture
       • Mixed pasture make maximum use of soil nutrients
       • Mixed pasture has better weed control effects
       • Mixed pasture increases soil fertility because of Nitrogen fixation
       • There is economy in use of fertilizers in mixed pasture .
       • There is better distribution of growth in a mixture of early and late maturity species (Any 8 x 1 = 8mks)
24.  
    1.  
       • Ability to produce large quantities of viable seeds e.g. pigweed and blackjack.
       • Weeds seeds remain viable in the soil for a long time waiting condusive germination conditions
       • Most weeds seeds are easily and successfully disposed
       • Some weed seeds have ability to propagate vegetatively eg. Couch grass
       • Some have elaborate or extensive root system useful in supporting the plant in nutrient absorptions of water upatake
       • Ability to survive in soil with low nutrient supply
       • Have short life cycles hence reaching maturity early. (7 x 1 = 7mks)
    2.  
       • Capital availability
       • Type of soil
       • Topography
       • Type of crop to be irrigated
       • Water availability (5 x 1 = 5mks)
    3.  
       • Good drainage
       • It is well aerated
       • Good depth
       • Good water holding capacity
       • Adequate supply of nutrients
       • Correct soil PH
       • Free from soil borne pests and diseases (Any 5 x 1 = 5mks)
         
         
    4.  
       • Superflous water
       • Capilary water
       • Hygroscopic water (3 x 1 = 3mks)
25.  
    1.  
       • They are highly volatile
       • They are highly soluble in water
       • They are highly hygroscopic
       • They are easily leached
       • They have a scorching / burning effect
       • They are highly corrosive
       • They “cake” easily
       • They have a short residual effect (Any 5 x 1 = 5mks)
    2.  
       • Include a grass ley in the programme whereby crops are alternated with certain grass to improve soil structure
       • Crops of the same family should not follow one another Deep rooted crops should be alternated with shallow rooted crops 
       • Crops that are difficult to weed should alternate with those that are easy to weed 
       • Crops that requires a lot of nutrients ( heavy feeders ) should come first followed by light feeders
       • Leguminous crops should be included in the cycle to improve soil fertility 
       • Crops associated with certain weeds should alternate with those that are not  (Any 5 x 2 = 10mks)
    3.  
       • Excess seedlings can be sold to earn income
       • It facilitates production of many seedlings in a small area
       • Routine management practices are easily and timely carried out than in the main seedbed
       • Facilitates planting of small seeds
       • It ensures transplanting of only healthy and strong seedlings
       • The crops takes a shorter time in the field
       • Tender seedlings are given maximum attention
       • Gives a higher germination percentage hence a lower seed rate is used (Any 5 x 1 = 5mks)