IBPS AFO flashcards

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

Soil pH

A measure of soil acidity or alkalinity on a 0-14 scale. Most field crops grow best between pH 6.0 and 7.5, while tea tolerates pH 4.5-5.5.

Khaira disease

A zinc deficiency disorder of rice marked by brown rusty spots on middle leaves and stunted growth. It is corrected by applying zinc sulphate to the soil or as a foliar spray.

Economic threshold level

The pest population density at which the damage likely to be caused equals the cost of control. Spraying below this level wastes money and harms natural enemies.

Rhizobium

A soil bacterium that forms nodules on legume roots and converts atmospheric nitrogen into forms the plant can use. Inoculation helps when the field lacks the specific strain.

Drip irrigation

A method that delivers water slowly and directly to the root zone through emitters. It typically saves 40-60% water compared with surface flooding and suits orchards and wide-row crops.

P2O5 to elemental phosphorus

Fertiliser labels express phosphorus as P2O5. Multiply by 0.44 to get elemental P, so a bag containing 26% P2O5 supplies about 11.4% elemental phosphorus.

Integrated Pest Management

A control strategy that combines monitoring, cultural, mechanical, and biological methods, using chemical pesticides only when pest density crosses the economic threshold level.

Red soils

Soils formed from crystalline rocks, reddish due to iron oxides, generally low in nitrogen, phosphorus, and organic matter. They dominate much of peninsular India and respond to organic manure.

Comprise vs consist of

'Comprise' takes a direct object with no preposition, as in 'the team comprises five members'. 'Consist of' requires 'of', and 'comprise of' is always wrong.

One of plus plural noun

In the pattern 'one of + plural noun + relative clause', the verb agrees with 'one', which is singular: 'One of the officers is absent.'

A bolt from the blue

An idiom meaning a sudden and completely unexpected event, usually unwelcome. It refers to lightning from a clear sky and is used for shocking news.

Para jumble opening sentence

The sentence that introduces the topic without back-referring pronouns or dependent connectors. It usually names the subject in full and is the anchor for the sequence.

Reading comprehension strategy

Read the questions first, then locate the exact sentence supporting each answer. The correct option restates the passage, while wrong options add unsupported claims or reverse cause and effect.

Cope with

The correct preposition after 'cope' is 'with', meaning to deal effectively with a difficulty. 'Cope up with' is non-standard and appears as a distractor in error-spotting questions.

Successive percentage change

Two successive changes of a% and b% equal a single change of a + b + ab/100. A 20% rise then a 20% fall gives a net 4% decrease, not zero.

Average speed, equal distances

When equal distances are covered at speeds x and y, average speed is 2xy/(x + y), the harmonic mean. It is always less than the arithmetic mean (x + y)/2.

Compound interest formula

CI = P(1 + R/100)^T - P when compounded annually. For half-yearly compounding, use rate R/2 and time 2T; for quarterly, use R/4 and 4T.

Alligation rule

A shortcut for mixing problems: the ratio of quantities of two components is (higher value - mean) : (mean - lower value). It applies to mixtures, averages, and profit questions.

Work rate shortcut

If A completes work in x days and B in y days, together they finish in xy/(x + y) days. Taking the LCM of x and y as total work units avoids fractions.

Boat and stream speeds

Downstream speed equals boat speed plus stream speed, and upstream equals boat speed minus stream speed. Boat speed is the average of the two, and stream speed is half their difference.

Sphere and cone volume

Sphere volume is (4/3)πr³ and cone volume is (1/3)πr²h. A cone is one-third of a cylinder with the same base and height.

Repeated replacement formula

When a fraction is repeatedly removed and replaced with another substance, final quantity of the original is initial × (1 - replaced/total)^n, where n is the number of operations.

Circular seating, facing centre

When people face the centre of a circle, a person's immediate left is the next position clockwise and immediate right is anticlockwise. The mapping reverses when they face outward.

Syllogism validity rule

A conclusion is valid only if it holds in every possible Venn diagram of the statements. 'Some A are B' never proves 'some B are not A'.

Either-or conclusion

In inequality questions, an either-or answer applies when two conclusions form a complementary pair, such as A > B and A ≤ B, and neither is individually true.

Blood relation notation

Draw a tree using + for male, - for female, = for marriage, and a vertical line for children. Never infer gender from a name; use only the stated relations.

Direction sense displacement

Track movement on coordinates with north as +y and east as +x. The shortest distance from start to finish is the square root of x² + y².

NABARD

The National Bank for Agriculture and Rural Development, set up in 1982, is the apex body for rural credit. It refinances cooperatives and regional rural banks and runs the Rural Infrastructure Development Fund.

Priority sector lending target

Domestic commercial banks must lend 40% of adjusted net bank credit to priority sectors, including 18% to agriculture. Regional rural banks and small finance banks have a 75% target.

Kisan Credit Card

A scheme giving farmers short-term credit for crop production and, in extended form, for dairy, fishery, and animal husbandry. Prompt repayers receive interest subvention.

PM Fasal Bima Yojana premiums

Farmer premium shares are 2% for kharif food and oilseed crops, 1.5% for rabi crops, and 5% for commercial and horticultural crops, with the government subsidising the balance.

Repo rate

The rate at which the RBI lends short-term funds to commercial banks against government securities. Raising it tightens liquidity and is a monetary policy tool against inflation.