CHICAGO, March 23 (Reuters) - The U.S. Department of Agriculture (USDA) will no longer regulate a genetically-modified corn developed by Monsanto Co to resist its dicamba herbicide, the agency said on Wednesday.

The move by the agency's Animal and Plant Health Inspection Service (APHIS), means it can now be planted without permits or any additional regulatory oversight from the agency.

Monsanto and other agricultural chemical companies produce seeds with built-in resistance to their weedkillers so that spraying with the chemicals does not destroy crops.

The corn line, known as MON87419, also resists glufosinate herbicide, the USDA said in a statement on its website.

Monsanto wants to use dicamba to diversify and provide long-term growth as its long-running glyphosate herbicide faces competition from generic products. In addition, the widespread use of glyphosate has contributed to the rise of weeds resistant to it and farmers are seeking alternatives.

The USDA also extended deregulation of Syngenta's MZIR098 corn, which is genetically engineered for both insect resistance and glufosinate-ammonium resistance.

(Reporting by Jo Winterbottom; Editing by Tom Brown)