Agricultural Entomology MCQ Question and Answer | Agriculture MCQ Question

Part of the plant where the characteristic symptom of Ufra disease in rice is very spectacular is Ear head.
The rice stem nematode Ditylenchus angustus causes “Ufra” disease in rice resulting in substantial yield losses. Although it is predominant in deep water rice in South and Southeast Asia, this nematode also infects irrigated and rainfed lowland rice.
Typical symptoms are a mosaic or chlorotic discolouration of emerging or emerged leaves; yellowish or pale green splash-patterns on affected leaves and sheaths; and appearance of brown to dark brown spots on leaves. Margins of affected leaves become corrugated. The collective symptoms are known as ufra disease.

Earias vitella is the pest of Cotton.
Spotted bollworm, Earias vittella (Fab.), is one of the most important insect pests of cotton, and host plant resistance is an important component of the management of this pest.
Earias vittella, an Asian "spotted bollworm", is a moth species in the family Nolidae. The species was first described by Johan Christian Fabricius in 1794. Most records are from Asia, Australia and certain Pacific islands.

Replication of DNA by rolling circle mechanism gives rise to a Concatamer.
A concatemer is a long continuous DNA molecule that contains multiple copies of the same DNA sequence linked in series. Concatemers are frequently the result of rolling circle replication, and may be seen in the late stage of bacterial infection by phages.
In rolling circle replication, a circular template of DNA is replicated as a long single-stranded DNA concatamer that spools off when a strand displacing polymerase traverses the circular template.

Cotton variety Abhadita is resistant to Bollworms.
Bt cotton is a genetically modified pest resistant plant cotton variety, which produces an insecticide to combat bollworms. Bt toxins are insecticidal to the larvae of moths and butterflies, beetles, cotton bollworms and flies but are harmless to other forms of life.
China first planted Bt cotton in 1997 specifically in response to an outbreak of cotton bollworm, Helicoverpa armigera, that farmers were struggling to control with conventional pesticides.

Transgenic crop which has highest area in world is Soybean.
India has the world's fifth largest cultivated area under genetically modified (GM) crops, at 11.4 million hectares (mh) in 2017.
In 2020, GMO soybeans made up 94% of all soybeans planted, GMO cotton made up 96% of all cotton planted, and 92% of corn planted was GMO corn. In 2013, GMO canola made up 95% of canola planted while GMO sugar beets made up 99.9% of all sugar beets harvested.

Nematode of industrial importance is Turbatrix aceti.
Turbatrix aceti (vinegar eels, vinegar nematode, Anguillula aceti) are free-living nematodes that feed on a microbial culture called mother of vinegar (used to create vinegar) and may be found in unfiltered vinegar. They were discovered by Pierre Borel in 1656.
Manufacturers normally filter and pasteurize their product before bottling, destroying the live bacterial and yeast culture that these nematodes require for sustenance.

Plecoptera insect is used as 'Ecological indicator'.
Most insects like beetles, ants, honeybees, and butterflies are used as biological indicators in this study because they are sensitive to even a slight change in the environment and are also used in monitoring various pollutants in environment.
All species of Plecoptera are intolerant of water pollution, and their presence in a stream or still water is usually an indicator of good or excellent water quality.
Due to their nymph's requirement for well-oxygenated water, the species is very sensitive to water pollution. This makes them important indicators for water quality.

Secondary metabolites like antibiotics are not essential for Log phase and exponential growth.
Microbial secondary metabolites, like antibiotics, pigments, growth hormones, antitumor agents, and others, are not essential for the growth and development of microorganisms, but they have shown great potential for human and animal health.
Secondary metabolites serve as competitive weapons used against other bacteria, fungi, amoebae, plants, insects, and large animals. It serves as metal transporting agent and agent of symbiosis between microbes and plants, nematodes, insects, and higher animals also as sex hormones.

1^st detailed classification of insects was done by Umaswati.
The first detailed classification of insects was done by Umaswati (0 - 100 AD). Classification of bees by the Indian physician Charaka (1200 - 1000 BC) and classification of ants, flies and mosquitoes by the surgeon Sushruta (100 - 200 AD) are the evidences for our earliest knowledge about insects.

Blue disease of cotton is transmitted by Aphids.
Cotton blue disease, also known as cotton leafroll disease, is caused by Cotton leafroll dwarf virus and can result in severe stunting of cotton plants.
The virus is transmitted between susceptible cotton varieties by cotton aphids (Aphis gossypii).