Odisha CHSE +2 Vocational Crop Production flashcards

32 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 the science and practice of field crop production and soil management, including tillage, sowing, nutrition, irrigation, and harvesting of field crops.

Cropping intensity

The ratio of gross cropped area to net sown area expressed as a percentage; a value above 100 shows that land grows more than one crop in a year.

Land Equivalent Ratio

The sum of the intercrop yields of each component divided by their sole-crop yields; a value greater than one indicates an intercropping advantage over sole cropping.

Harvest index

The ratio of economic yield to biological yield expressed as a percentage or fraction; it measures how efficiently a crop partitions dry matter into the harvested product.

Bulk density

The mass of oven-dry soil divided by its total volume, expressed in grams per cubic centimetre; it indicates compaction and pore space condition of the soil.

Cation exchange capacity

The total quantity of exchangeable cations a soil can hold, expressed in centimoles of charge per kilogram; it reflects clay and organic matter content and nutrient retention.

Base saturation

The percentage of the cation exchange capacity occupied by exchangeable basic cations such as calcium, magnesium, potassium, and sodium rather than hydrogen and aluminium.

Universal Soil Loss Equation

An empirical model estimating annual soil loss as the product of rainfall erosivity, soil erodibility, slope length and steepness, cover management, and support practice factors.

Law of the minimum

Liebig's principle that crop yield is governed by the essential nutrient present in shortest supply relative to plant need, not by nutrients available in excess.

Fertilizer grade

The guaranteed percentage composition of a fertilizer expressed as nitrogen, available phosphorus as P₂O₅, and soluble potassium as K₂O, in that fixed order.

Integrated nutrient management

The combined use of organic manures, biofertilizers, and mineral fertilizers to supply crop nutrients while maintaining soil fertility and reducing dependence on chemical fertilizers.

Biofertilizer

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

Heterosis

The superior vigour, yield, or adaptability of a first-generation hybrid over its parents; it is exploited commercially in crops such as maize, sorghum, and hybrid rice.

Pure line selection

A breeding method in which individual superior plants of a self-pollinated crop are selected, their progenies tested separately, and the best uniform progeny released as a variety.

Backcross breeding

A hybridization method in which a hybrid is repeatedly crossed back to a recurrent parent to transfer a specific desirable gene while recovering the recurrent parent's genetic background.

Cytoplasmic male sterility

A maternally inherited condition in which plants fail to produce viable pollen, allowing hybrid seed production without hand emasculation in crops such as rice and sorghum.

Seed certification

A quality assurance system in which seed produced under prescribed standards is inspected, tested, and labelled in classes from breeder through foundation to certified seed.

Seed germination percentage

The number of normal seedlings produced in a standard germination test divided by the total number of seeds tested, multiplied by one hundred.

Physical purity

The weight of pure seed of the designated variety expressed as a percentage of the total weight of the sample analysed, excluding other crop seed, weed seed, and inert matter.

Seed vigour

The sum of properties determining the potential of seed to germinate rapidly and produce normal seedlings under a wide range of field conditions, tested by stress methods.

Detasseling

The removal of tassels from female parent rows in hybrid maize seed production before pollen shed, preventing self-pollination and ensuring cross-pollination by the male rows.

Rhizobium inoculation

Treating legume seed with a culture of nitrogen-fixing bacteria that form root nodules and convert atmospheric nitrogen into forms the plant can use.

Critical irrigation stage

The growth stage at which water stress causes the greatest reduction in yield, such as panicle initiation in rice or crown root initiation in wheat.

Water use efficiency

The amount of crop yield produced per unit of water consumed, expressed as kilograms per hectare per millimetre or kilograms per cubic metre of water.

Available water capacity

The difference between field capacity and permanent wilting point; it represents the soil water that plants can absorb for growth and transpiration.

Economic threshold level

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

Pre-emergence herbicide

A herbicide applied to the soil surface after sowing but before weed seedlings emerge, killing germinating weeds through root or shoot uptake.

Integrated pest management

A decision framework combining cultural, mechanical, biological, and chemical control methods to keep pest populations below economic threshold levels with minimum pesticide use.

Effective field capacity

The actual area a machine covers per unit time in the field, calculated as theoretical field capacity multiplied by field efficiency to account for turns and stoppages.

Gross margin

The gross return from an enterprise minus its variable costs; it measures the contribution of an enterprise to covering fixed costs and generating profit.

Marketable surplus

The part of total farm production remaining after deducting home consumption, seed requirements, and other on-farm needs, which is available for sale in the market.

Green manuring

The practice of growing a leguminous crop such as dhaincha or sunhemp and ploughing it into the soil while green to add nitrogen and organic matter.