Agricultural Biology Practice Test

Parasexual hybridization involves the fusion of protoplasts from different species or varieties to create a hybrid, bypassing the sexual cycle.

Bordeaux mixture is a combination of copper sulfate and lime, used as an inorganic fungicide to control fungal diseases in plants.

Rotenone is a naturally occurring compound found in the roots of several tropical plants and is used as a broad-spectrum insecticide.

Clonal selection or vegetative propagation allows for the maintenance of hybrid vigour (heterosis) because it produces genetically identical offspring, preventing the segregation of traits that occurs in sexual reproduction.

Polyethylene glycol (PEG) is a common chemical agent used in plant tissue culture to induce the fusion of protoplasts.

Sonora and Lerma Rojo are famous high-yielding dwarf varieties of wheat introduced during the Green Revolution.

Coconut palm is called 'Kalpavriksha' or 'Kalpataru' in Sanskrit, meaning 'wish-fulfilling tree' because every part is useful. Mango, neem, and eucalyptus, while valuable, are not traditionally called Kalpavriksha.

Blue-Green Algae (BGA) are nitrogen-fixing organisms commonly used as biofertilizers in paddy (rice) fields to enhance soil fertility.

Bacillus subtilis is a well-known phosphate solubilizing bacterium that helps convert insoluble phosphorus into a form plants can absorb.

An intergeneric cross involves breeding between two different genera, which represents a very distant relationship compared to intervarietal or interspecific crosses.

Bacillus thuringiensis (Bt) produces toxins that are specifically lethal to certain insect pests, making it a valuable tool in biological pest control.

Pomato is a somatic hybrid produced by the fusion of protoplasts from potato and tomato plants.

Green manuring involves incorporating undecomposed green plant tissues into the soil to improve fertility. This practice typically increases crop yields by 30 to 50 percent depending on the crop and soil conditions.

Azospirillum is a well-known genus of nitrogen-fixing bacteria that forms associative symbiotic relationships with the roots of various grasses, including maize.

Plant breeding aims to improve crop performance by selecting or creating varieties that are disease resistant, high-yielding, and have desirable agronomic traits like early maturity.

Intensive agriculture, which involves continuous cropping without adequate replenishment of nutrients or rest periods, leads to soil exhaustion and reduced fertility over time.

Emasculation is a technique used in plant breeding to prevent self-pollination. It involves the removal of the anthers from a bisexual flower before they shed pollen.

BOD stands for Biochemical Oxygen Demand, which is the amount of dissolved oxygen needed by aerobic biological organisms to break down organic material present in a given water sample.

Heterosis, or hybrid vigour, is the phenomenon where the progeny of two genetically diverse parents exhibit superior traits compared to the parents.

Loamy soil is considered ideal for plant growth because it provides a balanced mixture of sand, silt, and clay, offering good drainage, aeration, and water retention.

Pyrethrins are natural insecticides derived from the flowers of certain species of Chrysanthemum.

Minamata disease is a neurological syndrome caused by severe mercury poisoning, which was famously linked to the release of methylmercury into Minamata Bay in Japan.

Acid rain is primarily caused by the atmospheric emission of sulfur dioxide and nitrogen dioxide, which react with water vapor to form sulfuric and nitric acids.

The White Revolution (also known as the Shah and People's Revolution) was a series of reforms launched in Iran in 1963.

According to the World Health Organization and various environmental standards, noise levels above 80 dB are generally considered the threshold for potential hearing damage and hazardous noise pollution.

Triticale is a man-made cereal crop created by crossing wheat (Triticum) and rye (Secale).

The Green Revolution, led by Norman Borlaug, began in Mexico in the 1940s and 1950s with the development of high-yielding wheat varieties.

Historical and archaeological evidence suggests that organized agriculture began in the Fertile Crescent, which includes the Nile Valley, around 10,000 years ago.

Herbicides are chemical substances specifically designed to kill or inhibit the growth of unwanted plants, commonly known as weeds.

Azolla is a small aquatic fern that has a symbiotic relationship with the cyanobacterium Anabaena azollae, which lives in its leaf cavities and fixes atmospheric nitrogen.

Vesicular arbuscular mycorrhizae (VAM) form symbiotic associations with plant roots and significantly enhance the uptake of immobile nutrients, particularly phosphorus.

Sharbati Sonora is a wheat variety developed in India through mutation breeding using gamma radiation on the Sonora 64 variety.

Historical data regarding fertilizer consumption in India varies by year, but 9.2 million tonnes is a frequently cited figure in older textbooks for this context.

Norman Borlaug is widely recognized as the Father of the Green Revolution for his work in developing high-yielding wheat varieties that saved millions from starvation.