V. Agricultural and Fishery Sciences (5%) Flashcards
- Per Department of Agriculture Administrative Order No. 4, series of 2022, the minimum inorganic fertilizer rates should be ___ bags/hectare (3 bags urea plus three bags 14-14-14 or three bags urea plus two bags 16-20-0 and one bag 0-0-60).
A. 5
B. 6
C. 7
D. 8
Answer: B
- Per BFAR standard, the intensive stocking density of tilapia is __ heads per square meter.
B. 3
B. 4-8
C. >8
D. 3-5
Answer: C
- Intensive fish stocking density needs _________ feeds.
A. Natural feeds
B. Commercial
C. Organic feeds
D. Plankton
Answer: B
- Per BFAR standard, the extensive stocking density of tilapia is __ heads per square meter.
A. 3
B. 4-8
C. >8
D. 3-5
Answer: A
- Tilapia fingerlings need feeds equivalent to ____% of body weight.
A. 2-5
B. 5-10
C. 10-15
D. 15-30
Answer: C
- Tilapia feeding frequency.
A. Once in 2 days
B. Once daily
C. 2-3 times daily
D. 3-4 times daily
Answer: C
7. A marketable size tilapia weighs \_\_\_ grams/head . A. >76 B. >81 C. >86 D. >91
Answer: D
- Tilapia fry needs feeds equivalent to ____% of body weight.
A. 2-5
B. 5-10
C. 10-15
D. 15-30
Answer: D
- How many mango seedlings are needed to be purchased for 1 hectare area if the planting density is 10 meters by 10 meters. Give 5% allowance in the number of seedlings purchased.
A. 100
B. 105
C. 150
D. 525
Answer: B Solution: No. of Seedlings = Safety Factor [Area in ha x 10,000 m2 /ha / Planting Density in m x m] = 1.05 [1 ha x 10,000 m2 /ha / (10 m x 10 m)] = 105 seedlings/hectare
- If the recommended rate of nitrogen is 90 kg/hectare, how many kilograms of urea fertilizer are to be applied per hectare using 46-0-0 urea fertilizer alone?
A. 195
B. 196
C. 198
D. 200
Answer: B
Solution:
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Computation procedure: To determine the fertilizer rate for a particular nutrient, multiply the
rate of the desired nutrient by 100 and divide by the percentage of the nutrient in the fertilizer
(Manitoba Soil Fertility Guide, 2022).
Fertilizer rate = (Rate of Desired Nutrient x 100) / Percentage of the Nutrient in the Fertilizer
= (90 kg/ha x 100) / 46
= 195.65 kg/ha
- Based on the experimental field’s soil analysis, the recommended fertilization rate for P2O5 is 45
kg/ha. What should be the fertilization application rate of P2O5 in kilograms/hectare if using 0-22-0
fertilizer alone?
A. 200
B. 202
C. 205
D. 207
Answer: C Solution: Fertilizer rate = (Rate of Desired Nutrient x 100) / % of the Nutrient in the Fertilizer = (45 kg/ha x 100) / 22 = 204.5 kg/ha
- Based on the farm’s soil analysis, the recommended fertilization rate for K2O is 16.8 kg/ha. What should be the weight per unit area in kilograms/hectare of K2O to be applied if using 0-0-60 fertilizer
alone?
A. 28
B. 82
C. 2.8
D. 8.2
Answer: A Solution: Fertilizer rate = (Rate of Desired Nutrient x 100) / % of the Nutrient in the Fertilizer = (16.8 kg/ha x 100) / 60 = 28 kg/ha
- If the recommended rate of nitrogen is 90 kg/hectare, how many bags of urea fertilizer are needed per hectare using 46-0-0 urea containing 50 kilograms per bag?
A. 195
B. 196
C. 198
D. 200
Answer: B
Solution:
Computation procedure: To obtain the number of bags of fertilizer, divide the fertilizer requirement in kg/hectare by the number of kilograms contained per bag, then round up (not
round off) to the nearest integer.
Fertilizer rate = (Rate of Desired Nutrient x 100) / % of the Nutrient in the Fertilizer
= (90 kg/ha x 100) / 46
= 195.65 kg/ha
No. of Bags = Fertilizer Requirement in kg/hectare / No. of Kilograms Contained per Bag
= 195.56 kg/ha / 50 kg/bag
= 3.91 bags/ha, round up to 4 bags/ha
- If tilapia stocking relies only on natural food source, how many tilapia fingerlings should be stocked in each of 50 experimental cages, each cage has a diameter of 1 meter and depth of 1
meter? Mortality safety factor is 7% for small cages.
A. 2
B. 3
C. 126
D. 162
Answer: B
Solution:
Tilapia extensive stocking density (relies only on natural food source): 3 heads/m2
Area of cage = 3.14 (1 m)2
/4 = 0.785 m2
Stocks = Density x Area x [1+ safety factor in ratio] = 3 x 0.785 x (1.07) = 3 heads/cage
