KANSAS CITY, Mo. (Reuters) - Genetically modified crops have not delivered promised benefits of fighting world hunger and raising poor farmers' incomes, according to a report by an international coalition of anti-biotech groups.

The report, compiled by a team of scientists, research organizations and farmers from several countries, also claims that biotech companies may be contributing to global hunger by using patents and other property rights to restrict traditional farming practices that save seed from year to year.

"This report details a sad and consistent history of corporate greed and scientific failure in agricultural biotechnology," Andrew Kimbrell, executive director of the Center for Food Safety in Washington D.C., said in a statement accompanying the report.

The 105-page report was issued by the Research Foundation on Science, Technology, and Ecology from India; the Tuscany government's Commission on Food and Agriculture from Italy; and the International Forum on Globalization in San Francisco.

"The commercial crops produced have done nothing to solve world hunger but instead have resulted in increased chemical use, lower yields and the destruction of family farms," Kimbrell said.

Release of the report, titled "Citizens Vote for GMO-Free Food," came as global biotech industry players gathered in San Francisco at the annual meeting of the Biotech Industry Organization.

BIO spokeswoman Lisa Dry brushed off the report's criticisms as "not based in reality."

"We know that more than 7 million farmers in 18 countries have adopted this technology. We see an increase every year," Dry said in an interview. "The facts are farmers want this. The products sell themselves based on merits and benefits."

In the report, the groups specifically seek to rebut claims made repeatedly by biotech supporters that genetically modified -- or GMO -- crops bring increased value to farmers and other agricultural industries.

The report cites several examples of lost markets because of consumers resisting GMO crops, including Canada's loss of $300 million in canola sales and a sharp decline in U.S. corn sales to Europe. It also claims that biotech crops require high input costs not matched by yield increases, and contaminate natural and organic crop varieties while stripping farmers of control over their crops.

The report says three countries, led by the United States, grow 90 percent of GMO crops with 10 percent in another 13 nations.