CHICAGO (Reuters) - China approved five genetically modified crops for import on Tuesday, the first in about 18 months, as representatives from the Asian country and the United States met in face-to-face talks to try to resolve trade disagreements.

Five other products, whose makers are known to be seeking approval of, were not given the green light by China’s agriculture ministry, however.

Some that were approved, including two canola varieties, had been waiting for six years. Others, like DowDuPont Inc's DWDP.N Enlist E3 soybeans, are more recent and were developed to challenge the historic dominance of Monsanto Co, now owned by Germany's Bayer BAYGn.DE, of the $40 billion U.S. soybean market.

U.S. farmers will not plant soybean seeds in large quantities unless they are approved by China, which until the trade war imported 60 percent of U.S. soybeans.

Below are the seed traits approved, their trade names and the companies that make them.

DAS-44406-6, known as Enlist E3 soybeans. Manufactured by DowDuPont, they are bred to resist glyphosate, glufosinate and 2,4-D for weed control and boosting yields.

DP 4114, Qrome, also produced by DowDuPont, is a corn product resistant to glufosinate and designed to protect against insects and increase yields.

SYHT0H2 soybean developed by Bayer Crop Science and Syngenta SYENF.PK but now held by German Chemical company BASF BASFn.DE. It is resistant to the herbicides glufosinate and Mesotrione, according to the biotech group ISAAA.

Bayer-owned Monsanto’s 88302 canola variety is tolerant to glyphosate during the reproductive flowering phase. It promised better control of certain tough weeds and a wider application window, according to a Bayer statement on Tuesday. It will be available this year to Canadian and U.S. farmers, and Bayer estimates 1 million planted acres in 2019.

BASF’s RF3 canola seeds are tolerant of Liberty glufosinate, an herbicide, according to the Canola Council of Canada.

Five other products known to be seeking approvals were not given the green light. Below are those seed traits and the companies that make them.

DAS-68416-4, known as Enlist soybeans. Like the next-generation Enlist E3 trait that was approved, the Enlist soy seed is a DowDuPont product. It is resistant to glufosinate and 2,4-D, according to ISAAA.

DowDuPont’s 81419-2 soybean trait was first submitted for approval in March 2014. It is resistant to glufosinate and has a Lepidoptera insect resistance, according to ISAAA.

DowDuPont’s Pioneer canola DP73496 was first submitted for approval in July 2012. It is resistant to glyphosate.

Bayer-owned Monsanto’s Roundup Ready alfalfa or J101. Resistant to glyphosate, it was submitted for approval in July 2011.

Another glyphosate-resistant Bayer alfalfa seed waiting for approval for over seven years, J163, also was not approved.