Agriculture (PSEB Senior Secondary Elective): Seasons, Soil Fertility and Field Decisions
The Agriculture domain of the PSEB Senior Secondary (+2) elective tests whether you can apply agronomic science to Punjab field conditions: crop and variety choice by season, soil fertility and fertilizer arithmetic, irrigation scheduling, plant protection and the economics of small holdings. Expect definition, numerical and diagnostic items together, so names alone rarely earn full marks.
Seasons and crop planning
Kharif crops are sown April–June and harvested September–October (rice, maize, cotton, moong, groundnut). Rabi runs October–March (wheat, gram, mustard, barley); zaid is the short summer slot for fodder and moong. Wheat sown after mid-November loses yield for every day of delay, so variety duration must match the sowing window - a short-duration rice such as PR 126 frees land early enough for timely wheat.
Soil fertility and fertilizer arithmetic
Recommendations are written as kg N, P2O5 and K2O per acre, never as kg of bagged fertilizer. Nitrogen is split into two or three doses to limit leaching and lodging; phosphorus and potash go basal at sowing. DAP carries 18% N with 46% P2O5, urea 46% N, and muriate of potash 60% K2O. Soil test values decide whether the blanket dose is raised or cut.
Plant protection
Answers should lead with integrated pest management: resistant varieties, seed treatment, timely sowing, sprays only at the economic threshold level, and rotation of chemical groups to slow resistance.
Worked example
Recommended dose for irrigated wheat is 50–25–12 kg per acre. Phosphorus: 25 ÷ 0.46 = 54.3 kg DAP, which also supplies 54.3 × 0.18 = 9.8 kg N. Remaining N = 50 − 9.8 = 40.2 kg, so urea = 40.2 ÷ 0.46 = 87.4 kg. Potash: 12 ÷ 0.60 = 20 kg MOP. Subtract the nitrogen hidden in DAP before buying urea.
Traps that cost marks
Buying urea for the full nitrogen dose and ignoring DAP's nitrogen; treating P2O5 and K2O as elemental P and K; applying all nitrogen basal; quoting pesticide dose as formulation instead of active ingredient; and placing rabi crops in kharif answers.