Two economic importance of tick,rat, grain weevil Weegy:
Rodents are of major economic importance, primarily as consumers of the grains that are the basic foodstuff for man. It has been estimated that rats and mice destroy up to one-third of grain crops under conditions of heavy infestation. [ Burrowing rodents may damage root crops. The muskrat (Ondatra zibethica) and nutria (Myocastor coypus), introduced into Europe as fur sources, have escaped and spread over much of Europe between the Baltic and the Alps. Their burrows, particularly in canal banks, have been a major source of damage to the drainage system, most especially in The Netherlands. A number of rodents serve as reservoirs for human diseases, such as bubonic plague, tularemia, scrub typhus, and others. The plague that ravaged Europe during the mid-14th century was transmitted by fleas from rats to humans. In view of their life history, weevils are of considerable economic importance, particularly in relation to agriculture. No part of a plant, from the roots to the seeds, is safe from the attacks of one or more species of weevil. Although it is mainly the larval stages that cause the most damage, the adults too can be quite destructive. Some species, such as the grain weevil (Sitophilus granarius), are serious pests of stored grains. Others, such as the cotton boll weevils (Anthonomus barbirostris), are responsible for widescale destruction of stored cotton in the United States, into which it was introduced in the 1890s from Latin America.
Read more: Weevils - Species, Plant, Insects, and Rostrum - JRank Articles http://science.jrank.org/pages/7362/Weevils.html#ixzz2AanJaN6h
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