explain the term transposonce give the name of Crop plant in which the Transposonse was first observed

Dear student 
Transposon is a DNA sequence that can change its position within a genome. This transposon can be cut out of its position and inserted into some other required places inside a genome. It can also replicate independently.
Transposons were first discovered in corn (maize) by American scientist Barbara McClintock. 
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