Nitrogen fixation by Rhizobium is increased in the presence of :
Most herbicide interfere with :
A large number of different herbicide classes inhibit photosynthesis by binding to the quinone-binding protein, D-1, to prevent photosynthetic electron transfer. Mostly they interfere with photolysis of water. Herbicides does not interfere with water absorption, translocation of sugar and CO2 absorption.
Pests resistant to insecticides have :
A widely cultivated rice variety which has solved food problem in Asia and has been developed by IRRI Manila (Philippines)
Some very special sources of genetic diversity have been identified during germplasm evaluation. For example, a thorough evaluation of O. sativa germplasm failed to find resistance to the grassy stunt virus. It was found, however, in just one accession of the closely related wild species, O. nivara (IRGC 101508) from India. IRRI breeders exploited this resistance and subsequently released IR 36, which was at one time the most widely cultivated variety of any cereal (Swaminathan, 1982). Few examples of germplasm have had a similar impact; however, a cursory analysis of rice pedigrees (e.g. IR 36) shows how wide the search has been for new germplasm capable of increasing productivity in rice cultivation.
Secondary home (Centre of production) of coffee is
Coffee was not native to the Americas and had to be planted in the country. The first coffee was grown by Native Americans. The first coffee bush in Brazil was planted by Francisco de Melo Palheta.Coffee production in Brazil is responsible for about a third of all coffee, making Brazil by far the world's largest producer, a position the country has held for the last 150 years.
Which of the following is the cyanobacterial group acting as biofertilizer ?
Which pesticide is lipophilic ?
Organochlorine compounds are highly lipophilic and can accumulate in fat-rich food such as meat and milk (Hernandez et al., 1994). Pesticides are introduced into cattle mainly through fodder or contaminated water used for household and public purposes (Sabbah and Bouguerra 1997).
In a gene bank, genetic material is stored in the form of :
Which of the following is a weedicide?
2, 4-D is a weedicide. 2,4-Dichlorophenoxyacetic acid is a common systemic herbicide used in the control of broadleaf weeds. It is a synthetic auxin (plant hormone) and one of the most widely used herbicides in the world. 2,4-D is a possible carcinogen as per WHO.2,4-D was one of the ingredients in Agent Orange, a herbicide widely used during the Vietnam War. 2,4-D is primarily used as a selective herbicide which kills many terrestrial and aquatic broadleaf weeds, but not grasses. It acts by mimicking the action of the plant growth hormone auxin, which results in uncontrolled growth and eventually death in susceptible plants.Weed is a wild plant growing where it is not wanted and in competition with cultivated plants. Weedicide is the chemical which kills weeds.
The aquatic Fern, which is an excellent biofertilizer is :
Botanical name of Jojoba is:
Jojoba (Simmondsia chinensis) is a shrub. It is the sole species of the family Simmondsiaceae, placed in the order Caryophyllales. It is grown commercially for its oil, a liquid wax ester extracted from the seed.
The pesticide most toxic to vertebrates are :
Organophosphate (OP) compounds are the most widely used group of insecticides in the world. Their acute toxicity causes a hazard both to professional and amateur users. OPs were first recognised in 1854, but their general toxicity was not established until the 1930s. Tetraethyl pyrophosphate (TEPP) was the first OP insecticide, which was developed in Germany during World War Two as a by-product of nerve gas development. OPs are all derived from phosphoric acid. They are generally among the most acutely toxic of all pesticides to vertebrate animals. They are also unstable and therefore break down relatively quickly in the environment. So, organo phosphates are more toxic to vertebrates compared to organo chlorine, carbamates and parathion. Thus, option A is correct and other options are wrong.
What is triticale?
Triticale is an intergeneric hybrid of wheat and rye. The first one was bred in laboratories during the late 19th century in Scotland and Germany.
The bioconcentration of DDT in the body fat of Indian people :
Most of organochlorine pesticides are highly soluble in fat of animals. Further, these chemicals are resistant to be metabolized, so they start accumulating in the bodies of animals.
In India due to prolonged use of DDT, 13-31 ppm of DDT can be detected in the body fat of people, which is highest in the world. Thus, the correct answer is option C.
Integrated pest management (IPM) is based on :
Which of the following is a chlorinated hydrocarbon ?
Crossing with wild relatives is beneficial because it helps in the transfer of gene of ?
Green manuring increases crop yield by :
Thuriocide is :
Genetic erosion is due to :
Genetic erosion is a process whereby an already limited gene pool of an endangered species of plant or animal diminishes even more when individuals from the surviving population die off without getting a chance to meet and breed with others in their endangered low population. Low genetic diversity in a population of wild animals and plants leads to a further diminishing gene pool, inbreeding and a weakening immune system and fast tracks that species towards eventual extinction.
Potato got resistance to phytopthora infestans from
Late blight caused by the oomycete, Phytophthora infestans is the most destructive disease in potato cultivation worldwide. New, more virulent P. infestans strains have evolved which overcome the genetic resistance that has been introgressed by conventional breeding from wild potato species into commercial varieties. R genes (for single-gene resistance) and genes for quantitative resistance to late blight are present in the germplasm of wild and cultivated potato. The species Solanum demissum proved to be an important source of resistance, and by conventional plant breeding (crossing and back-crossing) in the 1940s and 1950s this resistance was bred into commercial potato cultivars. Four major resistant genes (termed R genes) were discovered and were introduced successively into commercial cultivars. Thus, the correct answer is option A.
Which of the following is an effect of herbicide
Herbicides, also commonly known as weed killers, are pesticides used to kill unwanted plants. Selective herbicides kill specific targets, while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often synthetic mimics of natural plant hormones. Herbicides interfere with photolysis of water, inhibits O2 evolution and also inhibits translocation of organic solutes. Thus, option D is correct.
Liquid wax similar to sperm whale oil obtained from
Which of the following is the examples of biofertilizers ?
A biofertilizer is a suspension of the living organism which remains in close association with the soil and increases the fertility of the soil. It is applied to plant surfaces, or soil colonizes the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. Blue-green algae is a free living nitrogen fixing bacteria. So, BGA has been recommended as a biofertilizer. VAM plays a great role in inducing plant growth. VAM are symbiotic entophytic soil fungi, which colonize the roots of approximately 80% plants. VAM also is used as biofertilizer.
So, the correct answer is option C.
Which of the following bacterium is associated with production of bioinsecticide?
Bacillus thuringiensis (Bt) is a bacteria that can infect and kill insects and thus, it is used as an insecticide. Alfalfa webworms killed by Bacillus thuringiensis. The insecticidal activity of Bt was first discovered in 1911. However, it was not commercially available until the 1950s. In recent years, there has been tremendous renewed interest in Bt.
Shoot tip culture are preferred for inter national exchange of germplasm because
Which of the following organism derives energy for N2 fixation by performing photosynthesis ?
Anabaena-Azollae is a small filamentous phototrophic cyanobacteria generally seen as a multicellular organism with two distinct, interdependent cell types. It is a small, circular, photoautotrophic vegetative cell that performs oxygenic photosynthesis and is typically blue green in color. Since it is a phototrophic cyanobacteria, it derives energy for N2 fixation by performing photosynthesis. Thus, option A is correct.
Largest group of insecticide of plant origin are –
A pyrethroid is an organic compound similar to the natural pyrethrins produced by the flowers of pyrethrums (Chrysanthemum cinerariaefolium and C. coccineum). Pyrethroids now constitute the majority of commercial household insecticides. In the concentrations used in such products, they may also have insect repellent properties and are generally harmless to human beings in low doses but can harm sensitive individuals. Pyrethroids are axonic excitoxins, the toxic effects of which are mediated through preventing the closure of the voltage-gated sodium channels in the axonal membranes. The sodium channel is a membrane protein with a hydrophilic interior. This interior is a tiny hole which is shaped precisely to strip away the partially charged water molecules from a sodium ion and create a favorable way for sodium ions to pass through the membrane, enter the axon, and propagate an action potential. When the toxin keeps the channels in their open state, the nerves cannot repolarize, leaving the axonal membrane permanently depolarized, thereby paralyzing the organism. So, pyrethroids are largest group of insecticides of plant origin. Thus, option C is correct.
Latex of which plant is a substitute for para rubber ?
Natural insecticide obtained from –
Which of the following is not a biofertilizer
A biofertilizer is a living microorganism or made up of dried microorganisms. It is applied to plant surfaces, or soil colonizes the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. Biofertilizers such as Rhizobium, Azotobacter, Azospirilium, mycorrhiza and blue-green algae have been in use for a long time.
So, the correct answer is option B.
Which of the following is example of new crop?
Jojoba is a native shrub of the Sonoran, Mojave and Baja California deserts of Arizona, California, and Mexico as well as the southernmost portion of the California Floristic Province. It is the sole species of the family Simmondsiaceae, placed in the order Caryophyllales. Jojoba is grown commercially for its oil, a liquid wax ester, extracted from its seed. Parthenium argentatum Gray, commonly known as the Guayule is a flowering shrub in the aster family, Asteraceae, that is native to the southwestern United States and northern Mexico. Leucaena leucocephala is a small, fast-growing mimosoid tree native to southern Mexico and northern Central America (Belize and Guatemala), but is now naturalized throughout the tropics. Common names include white leadtree, jumbay, and white popinac. So, all the three are examples of new crops. Thus, option D is correct and other options are wrong.
DDT is a :
Which one of the following plant is commonly used as green manure ?
One of the following crops produces recalcitrant seeds :
Recalcitrant seeds (sometimes known as unorthodox seeds) are seeds that do not survive drying and freezing during ex-situ conservation. Moreover, these seeds cannot resist the effects of drying or temperatures less than 10oC thus, they cannot be stored for long periods like orthodox seeds because they can lose their viability. Plants that produce recalcitrant seeds include avocado, mango, mangosteen, lychee, tea, cocoa, rubber tree, some horticultural trees, and several plants used in traditional medicine such as species of Virola and Pentaclethra.
Thus, the correct answer is option C.
The chicory powder which is mixed with coffee powder is obtained from
Which of the following is a microbial pesticide ?
The use of predator to control a pest is called :
Which of the following Pairs is mismatched ?
Azospirillum inoculations are recommended mainly for sorghum, millets, maize, sugarcane and wheat.
Mycorrhizal biofertilizers can be used for pine trees.
Rotenone is an odourless, colourless, crystalline ketonic chemical compound used as a broad-spectrum insecticide, piscicide, and pesticide. It occurs naturally in the seeds and stems of several plants, such as the jicama vine plant and the roots of several members of Fabaceae.
VAM is a biofertilizer and not a mycoherbicide.
So, the correct answer is option C.
Bio pesticide include –
Biopesticides are the type of pesticides in which the living organisms are used for the destruction of the pests. They are used in the methods of pest management. This method focuses on the control of pests by using predators or pathogens or enemies of the pests and insects. Biopesticides are the pesticides derived from natural materials. Bioinsecticides and bioherbicides come under the category of biopesticides. Bioinsecticides are used for the killing of pests and insects. Bioherbicides are used for the elimination of unwanted weeds and herbs.
Thus, the correct answer is option C.
Sesbania rostrata is preferred as green manure over other species because -
Mycorrhiza work's as -
Which of the following groups of herbicides is derived from urea, and is used for controlling weeds in tea, tobacco and cotton ?
Which of the following pest is eradicated by sterilisation technique?
Azolla increases rice productivity due to its association with -
Which of the following pairs serve as biofertilizers?
Carbamates are used as a
The carbamates are used in agriculture as insecticides, fungicides, herbicides, nematocides, or sprout inhibitors. In addition, they are used as biocides for industrial or other applications and in household products. A potential use is in public health vector control. Thus, these chemicals are part of the large group of synthetic pesticides that have been developed, produced, and used on a large scale in the last 40 years. Thus, option D is correct.
One of the following is a source of rubber:
Which insect was used to check the spread of cacti ?
Guayule is –
Bacillus thuringiensis is used to control-
Bacillus thuringiensis (or Bt) is a Gram-positive, soil-dwelling bacterium, commonly used as a biological pesticide. Many crystal-producing Bt strains, though, do not have insecticidal properties. The subspecies israelensis is commonly used for control of mosquitoes and of fungus gnats.
Which of the most important source of food and fodder?
In 1984 Bhopal gas tragedy was caused due to leakage of -
Which of the following plant is used as green manure ?
Which of these is a new crop ?
Which of the following plants is most commonly used as green manure in India?
Organo phosphates inhibit cholinesterase which of the following is a cholinesterase inhibitor -
Pesticides are chemicals that are used to destroy pests and thus increase crop productivity. They are often persistent, induce resistance and ecological imbalance. Malathion is an organophosphate pesticide which affects the nervous system. It inhibits the action of acetylcholinesterase enzyme which leads to accumulation of acetylcholine at the synapse.
So, the correct answer is option B.
Which of the following statement is incorrect about D.D.T. ?
DDT (dichlorodiphenyltrichloroethane) is a colourless, crystalline, tasteless and almost odourless organochloride known for its insecticidal properties. It is a non-biodegradable, water-insoluble, chlorinated hydrocarbon once used worldwide as a major insecticide, especially in agriculture. In recent years, knowledge of its adverse impact on the environment has led to restrictions in its use. It is lipophilic, so, undergo bioconcentration when it enters into food chain. Milk is a carrier of DDT cause, DDT enters into food chain. Thus, the correct answer is option D.
A gene bank is a place where valuable plant material is preserved in viable condition-gene bank are part of -
VAM (Vesicular arbuscular mycorrhizae) represents
What will happen if a wheat field is inoculated with bacterium Rhizobium ?
Rhizobium is an important symbiont for legumes but it plays an important role with nonlegumes by producing growth hormones. When wheat is inoculated with Rhizobium, no effects are observed in terms of growth and yield, which indicates that uptake of soil nitrogen is not seen as in legumes.
Match list-I (bioinsecticidal compound) with list-II (plant species) and select the correct answer –
(A) (B) (C) (D)
(1) P Q R S
(2) Q P R S
(3) S R Q P
(4) Q P R S
The seeds which can tolerate reduction in moisture and temperature are called –
What is the potential use of guayule (Parthenium argentatum)?
Most insecticides attack upon insects on their–
Most insecticides used nowadays are in organophosphate and carbamates class. This interfere the working process of the nerve cell and hence affects the nervous system.
All of the following is a part of IPM (Integrated Pest Management) except-
BGA is chiefly used as biofertilizer in the crop of
"Sporeine" is used to control-
Centre of origin of Groundnut is -
Which one of there is not correctly matched ?
Seeds of different cereals and legumes are -
The seeds that can tolerate drying and can remain viable for years are called orthodox seeds. These seeds are stored at low temperatures by drying them such that the moisture content is less than 10%. The seeds are stored till the next sowing period. Cereal and legume seeds are of orthodox type. Thus the correct answer is option A.
The material of biological origin, which is used to maintain and improve soil fertility is -
The first bioinsecticide to be developed on a commercial scale was -
The first inorganic pesticide to be used commercially was -
Bordeaux mixture (also called Bordo Mix) is a mixture of copper(II) sulfate (CuSO4) and slaked lime (Ca(OH)2) used as a fungicide. It is used in vineyards, fruit-farms and gardens to prevent infestations of downy mildew, powdery mildew and other fungi. It is sprayed on plants as a preventative; its mode of action is ineffective after a fungus has become established. It was invented in the Bordeaux region of France in the late 19th century. If it is applied in large quantities annually for many years, the copper in the mixture eventually becomes a pollutant. So, it is the first inorganic pesticide to be used commercially compared to Burgundy mixture, DDT and 2,4-D.
Which of the following statements is incorrect ?
Crops with recalcitrant seed include -
Botanical name of tea is
Pulses belong to the family of-
Leguminosae is a part of a major group Angiosperms (Flowering plants) that consist the pulses.
The Fabaceae or Leguminosae, are generraly referred to as LEGUMES. They are economically important family of flowering plants.
Pulses, generally, the dry seeds are cunsumed by humans on a large scale and they are a significant source of protein, dietary fiber, carbohydrates and dietary minerals.
Many cereals, some fruits and tropical roots are a part of Leguminosae have been a staple human food for millennia.
Species of Leguminosae that are a part of The Plant List belong to 917 plant genera.
Richest source of protein among the following is -
Lycopersicum esculentum is the botanical name of-
The tomato is the edible, often red fruit/berry of the nightshade Lycopersicum esculentum, commonly known as a tomato plant. The species originated in the South American Andes and its use as a food originated in Mexico and spread throughout the world following the Spanish colonization of the Americas. It's many varieties are now widely grown, sometimes in greenhouses in cooler climates. Thus, the correct answer is option D.
Hemp fibres belong to -
Potato and tomato have come from
The potato is a starchy, tuberous crop from the perennial nightshade Solanum tuberosum. In the Andes (South America), where the species is indigenous, there are some other closely related cultivated potato species. Potatoes were introduced outside the Andes region approximately four centuries ago.
The tomato is the edible, often red fruit/berry (Solanum lycopersicum). The species originated in the South American Andes and its use as a food originated in Mexico, and spread throughout the world following the Spanish colonization of the Americas. Thus, option D is correct.
Ficus elastica (Indian Rubber plant) is a member of-
Morphine is obtained from
Three crops that contribute maximum to global food grain production are -
Somaclonal variations appears in -
First transgenic plant was tobacco and it contain resistant gene for -
First genetically modified plant, tobacco and was engineered for herbicide resistance. Tobacco plant was produced in 1982.
Inbreeding depression mainly related with -
Inbreeding depression is the reduced biological fitness observed in a population due to inbreeding or breeding of related individuals. Self pollination is the transfer of pollen from Anther to the stigma of the same flower or another flower of the same plant, so it leads to inbreeding depression.
Pomato is -
Embryoid is -
Any cell of the female gametophyte or sporophytic tissue around the embryo sac may give rise to an embryo and such embryos are called as non-zygotic embryos. Embryoid is a mass of plant tissue that resembles embryo. These are formed from single cells in tissue culture. So, Embryoid is called as a non-zygotic embryo.