Explanation

• A subsoiler is a deep-tillage implement used to break compacted soil layers beneath the normal ploughing depth.
• It improves soil aeration, water infiltration, and root penetration without necessarily turning over the soil.

Additional information:

• Primary tillage: The initial major operation to loosen soil.
• Secondary tillage: Breaks clods and prepares a fine seedbed.
• Zero tillage: Seeds are planted with minimal soil disturbance.

Last verified on 16-10-2026

Explanation

• Alluvial deposits: Soil, sand, silt, and gravel transported and deposited by flowing water, especially rivers and streams.

Additional information:

• Alluvial soils are often fertile because rivers deposit nutrient-rich sediments on floodplains.
• The Indus River and its tributaries have formed extensive alluvial plains in Pakistan.

Last verified on 16-10-2026

Explanation

• Consumptive water use refers to water used by plants for growth and metabolic activities.
• It is mainly lost through transpiration, along with evaporation from the soil and plant surfaces.

Additional information:

• Evaporation: Water changes from liquid to vapour from soil or other wet surfaces.
• Transpiration: Water vapour escapes from plants, mainly through stomata in their leaves.

Last verified on 16-10-2026

Explanation

• Dew point temperature is the temperature at which air becomes saturated when cooled at constant pressure without changing its water-vapour content.
• At the dew point, actual vapour pressure equals saturated vapour pressure, and condensation begins if cooling continues.

Last verified on 16-10-2026

Explanation

• Amino acids are the building blocks of proteins.
• Proteins are formed when amino acids join together by peptide bonds.
• Proteins are essential for growth, repair, and body functions.
• There are 20 standard amino acids used to make proteins.

Verified & Updated

Explanation

• Apple is a deciduous fruit tree. 
• It sheds its leaves during autumn as it enters winter dormancy.
• Other examples include pear, peach, and plum trees.

Last verified on 16-10-2026

Explanation

• In chain surveying, the area is divided into a framework of triangles.
• Because triangles are simple to measure and plot accurately.
• The preferred method is triangulation, using measured survey lines and offsets to locate details.
• Well-conditioned triangles, ideally with angles between 30∘ and 120∘, help reduce measurement errors.

Last verified on 16-10-2026

Explanation

• Nematicide seed treatment: Appropriate nematicides can protect seedlings against certain plant-parasitic nematodes when the product is registered for the crop and target pest.
• Crop rotation: Growing non-host crops can reduce nematode populations in the soil.
• Resistant varieties: Planting resistant soybean varieties is an effective method of managing specific nematode species.

Last verified on 16-10-2026

Explanation

• The total depth of water needed by a crop during its entire growth period.
• It ensures the crop receives enough water for optimal growth from sowing to harvest.
• This total water requirement is called Delta.

Additional information:

• Delta varies depending on crop type, climate, and soil texture.
• It is measured in millimeters or cubic meters per hectare.

Last verified on 24-01-2026

Explanation

• Bar harrow: Used for shallow tillage and can uproot or dislodge weeds, helping to control them in agricultural fields.

Additional information:

• Rotavator: Breaks soil clods and prepares a fine seedbed; it can also incorporate weeds into the soil.
• Plank: Used mainly for levelling soil and pressing it lightly after tillage.
• Disc plough: Used for primary tillage, cutting and turning soil.

Last verified on 16-10-2026