Calculations on Expected Yields or Theoretical Yield of Some Important Crops
Question: Estimate the yield of sugarcane, cane juice, sugar and jaggery in tonnes per hectare from the following observations.
Given Data:
- Average number of millable canes per clump = 15
- Average weight of canes = 600 g
- Spacing of clumps = 90 cm × 60 cm
- Percentage of extractable juice in canes = 70%
- Percentage of sugar in juice = 16%
- Percentage of jaggery in juice = 20%
Solution
1. Yield of sugarcane in tonnes per hectare
Yield of sugarcane = (Average weight of canes × Area × Number of millable canes per clump) / (1000 × 100 × 10 × Spacing of clumps in m²)
= (600 × 10,000 × 15) / (1000 × 100 × 10 × 0.9 × 0.6)
= 166.67 tonnes/ha
2. Expected cane juice yield
Cane juice yield = Sugarcane yield × Percentage of extractable juice / 100
= (166.67 × 70) / 100
= 116.67 tonnes/ha
3. Expected cane sugar yield
Cane sugar yield = Cane juice yield × Percentage of sugar in juice / 100
= (116.67 × 16) / 100
= 18.67 tonnes/ha
4. Expected jaggery yield
Jaggery yield = Cane juice yield × Percentage of jaggery in juice / 100
= (116.67 × 20) / 100
= 23.33 tonnes/ha
Final Answer
- Sugarcane yield = 166.67 tonnes/ha
- Cane juice yield = 116.67 tonnes/ha
- Cane sugar yield = 18.67 tonnes/ha
- Jaggery yield = 23.33 tonnes/ha
Estimate the tuber yield of potato in quintals per hectare from the data given below.
Given Data:
- Spacing = 60 cm × 25 cm
- Average number of tubers per plant = 14
- Average weight of tubers = 35 g
Solution
Formula:
Yield of tubers (qt/ha) = (Area × Average number of plants × Average number of tubers per plant × Average weight of tubers in grams) / (Plant spacing in m² × 1000 × 100)
Step 1: Convert spacing into metres.
Spacing = 0.60 m × 0.25 m
Step 2: Substitute the values.
Yield = (10,000 × 14 × 35) / (0.60 × 0.25 × 1000 × 100)
Yield = 4,900,000 / 15,000
Yield = 326.67 quintals/ha
Final Answer
The estimated tuber yield of potato is 326.67 quintals per hectare.
Estimate the yield of wheat grains and straw from the observations given below.
Given Data:
- Spacing = 20 cm × 3 cm
- Average number of effective tillers per plant = 3
- Average number of grains per panicle = 32
- Test weight = 40 g
- Grain-to-straw ratio = 1:1.5
Solution
1. Calculate the yield of wheat grains
Yield of wheat grains (t/ha) = (10,000 × Number of effective tillers per plant × Number of grains per panicle × Test weight in grams) / (Spacing in m² × 1000 × 1000 × 100 × 10)
Substituting the values:
Yield = (10,000 × 3 × 32 × 40) / (0.20 × 0.03 × 1000 × 1000 × 100 × 10)
Yield of wheat grains = 6.40 tonnes/ha
2. Calculate the yield of wheat straw
Grain-to-straw ratio = 1:1.5
Yield of wheat straw = Yield of wheat grains × 1.5
= 6.40 × 1.5
Yield of wheat straw = 9.60 tonnes/ha
Final Answer
- Yield of wheat grains = 6.40 tonnes/ha
- Yield of wheat straw = 9.60 tonnes/ha