UPMSP Intermediate Agronomy flashcards

36 cards. Read the term and the definition here. The deck at the top of this page is optional.

Agronomy

The branch of agriculture dealing with field crop production and soil management, integrating genetics, soil science, plant physiology and economics to optimise yield and sustainability at field scale.

Harvest index

Ratio of economic yield to total biological yield, expressed as a fraction or percentage. It indicates how efficiently a crop partitions dry matter into the harvested product.

Leaf area index

Total one-sided leaf area per unit ground area. LAI determines light interception and crop growth rate; optimum values vary by crop and canopy architecture.

Land equivalent ratio

Sum of intercrop yields divided by the corresponding sole crop yields. A value greater than one indicates an advantage of intercropping over sole cropping.

Cropping intensity

Total cropped area divided by net sown area, multiplied by 100. It measures how many crops are grown on the same land in a year.

Relay cropping

A multiple cropping practice in which the next crop is sown into the standing previous crop before its harvest, extending the growing period and improving land use efficiency.

Bulk density

Oven-dry soil mass divided by its total volume, expressed in grams per cubic centimetre. It indicates compaction and porosity status of a soil.

Cation exchange capacity

Total quantity of exchangeable cations a soil can hold, expressed in centimoles of charge per kilogram. Higher values indicate greater nutrient retention and buffering.

Sodic soil

Soil with exchangeable sodium percentage above 15, pH above 8.5 and poor infiltration. Gypsum application followed by leaching is the standard reclamation method.

Law of the minimum

Liebig's principle stating that crop yield is limited by the nutrient present in shortest supply relative to plant needs, regardless of other nutrients being abundant.

Integrated nutrient management

Combining chemical fertilizers, organic manures, biofertilizers and crop residues to supply nutrients, maintain soil fertility and reduce dependence on inorganic sources.

Zinc deficiency symptom

Interveinal chlorosis with small leaves and shortened internodes, often appearing on younger leaves. Common in rice and wheat on high-pH soils.

Zero tillage

A conservation tillage practice in which the seed is placed in undisturbed soil with minimal disturbance, retaining crop residues on the surface to reduce erosion and conserve moisture.

Ploughing depth

Depth of primary tillage, classified as shallow (10-15 cm), medium (15-25 cm) or deep (25-40 cm). Deep ploughing breaks hardpan and buries weed seeds.

Laser land levelling

Precision levelling of fields using a laser-guided scraper. It improves water distribution uniformity, reduces irrigation water use and enhances crop establishment.

Universal soil loss equation

A = R x K x LS x C x P, where rainfall erosivity, soil erodibility, slope length and steepness, cover management and support practice factors estimate annual soil loss.

Contour bunding

Construction of earthen bunds along contours on sloping land to intercept runoff, reduce slope length and conserve soil and moisture for crop production.

Seed rate

Quantity of seed sown per unit area, calculated from target plant population, test weight, germination percentage and purity to achieve optimum crop stand.

Rhizobium seed treatment

Inoculation of legume seeds with nitrogen-fixing bacteria before sowing to enhance nodulation and biological nitrogen fixation. It must not be mixed with chemical fungicides.

Dibbling

Sowing method in which seeds are placed individually in holes at a predetermined spacing and depth, commonly used for large seeds like maize and cotton.

Irrigation water use efficiency

Crop yield produced per unit of irrigation water applied. It measures the effectiveness of irrigation scheduling and application methods in crop production.

Critical growth stage

A crop stage at which water stress causes the greatest yield reduction, such as crown root initiation in wheat and panicle initiation in rice.

Drip irrigation

Application of water directly to the root zone through emitters at low pressure and flow rate. It saves water and is suited to wide-row crops.

Critical period of weed competition

The crop growth interval during which weed competition most reduces yield, for example 30-60 days after sowing in wheat. Weed control must target this window.

Herbicide selectivity

The ability of a herbicide to kill weeds without injuring the crop, based on differential absorption, translocation, metabolism and placement of the chemical.

Economic threshold level

Pest population density at which control measures should be initiated to prevent the pest from reaching the economic injury level and causing unacceptable loss.

Phalaris minor

A major grassy weed of wheat in the rice-wheat system, also called little seed canary grass. It competes strongly and has developed resistance to some herbicides.

Sugarcane sett planting

Planting sugarcane using stem cuttings with three buds placed in furrows at about 90 cm row spacing, followed by earthing up and irrigation for establishment.

Kharif season

The monsoon crop season from June to October in Uttar Pradesh, when crops such as rice, maize, pigeonpea and groundnut are sown with rainfall.

Yellow rust of wheat

A fungal disease caused by Puccinia striiformis, producing yellow pustules in stripes on leaves. Cool, moist weather favours it; resistant varieties are the main control.

Integrated pest management

A strategy combining monitoring, cultural, mechanical, biological and chemical tactics, using pesticides only when pest populations exceed the economic threshold level.

Grain storage moisture

The safe moisture content for storing cereals, generally 12-14 percent; oilseeds require 8-10 percent. Higher moisture promotes mould, insects and spoilage.

Zero-till drill

A seed drill designed to sow seed into undisturbed soil with minimum disturbance, often with a residue-cutting coulter, used in conservation agriculture systems.

Green manuring

Growing a leguminous crop such as sunhemp or Sesbania and ploughing it into the soil while green to add organic matter and nitrogen for the following crop.

Biofertilizer

A preparation containing living microorganisms such as Rhizobium, Azotobacter or phosphate-solubilising bacteria that enhances nutrient availability to crops when applied to seed or soil.

Conservation agriculture

A farming system based on minimum soil disturbance, permanent soil cover with crop residues and crop diversification, improving soil health and reducing erosion and water use.