Two more unshu orange hybrids from South Korea would be OK’d for shipment to the U.S. under a proposed rule issued by the U.S. Department of Agriculture.

The July 29 rule said the citrus hybrids would be allowed into the U.S. under existing rules for South Korea unshu imports.

The comment deadline for the regulation is Sept. 29.

The USDA said increased unshu imports won’t have a significant effect on U.S. citrus growers. The Republic of Korea is expected to supply 2,000 metric tons or less of unshu oranges to the U.S. market, which will equal about 1.4% of all mandarin imports and 0.3% of domestic supply.

American growers do not commercially produce unshu oranges, but do grow similar mandarin varieties. U.S. output of mandarin citrus varieties grew from 225,000 metric tons in 2007 to almost 500,000 metric tons in 2012, according to the USDA. The value of the U.S. mandarin crop climbed from $141 million in 2007 to $336 in 2012.

Harvest and marketing of mandarin oranges are most active between Jan. 1 and March 31 in California, and between Nov. 15 and March 15 in Florida, according to the proposal. Imports of mandarin citrus varieties averaged about 142,000 metric tons per year between 2010 and 2012, with Chile, Spain, Peru and Morocco the main sources.