Crop Production: Field Crops, Cropping Systems, and Package of Practices
Crop Production tests field-crop husbandry and the logic of cropping systems. You must connect seed rate, spacing, sowing time, nutrient dose, irrigation critical stages and harvest decisions to a crop and agro-climate.
Cropping systems
- Sole cropping grows one crop in a field. Mixed cropping grows two or more crops without a fixed row arrangement. Intercropping uses definite rows; relay cropping plants the next crop before the first is harvested. Sequence cropping is a planned order of crops.
- Cropping intensity = total cropped area ÷ net sown area × 100. It measures how many times the net area is cropped in a year.
- Package of practices is crop- and region-specific. A recommendation from one zone should not be transferred blindly to another.
Worked example
Maize is planted at 60 cm × 20 cm. Area per plant = 0.60 × 0.20 = 0.12 m2. Plants per hectare = 10,000 ÷ 0.12 = 83,333. If 5% of plants are lost to gaps and mortality, harvestable population = 83,333 × 0.95 = 79,167 plants/ha. Reasoning: convert spacing to area per plant, then divide the hectare area by that figure. Always state whether the answer is target or harvestable population.
Traps that cost marks
Do not confuse mixed cropping with intercropping. Do not use gross plot area when the question asks for net harvested area. Do not quote a seed rate without checking germination and seed weight. Critical irrigation stages are not the same as the total number of irrigations. In rotation questions, consider legume effects, allelopathy and shared pests, not just income.