A shocking report has warned that the world is less than 40 years away from a food shortage that will have serious implications for people and governments, a top scientist from the U.S. Agency for International Development said, according to Indo-Asian News Service.

"For the first time in human history, food production would be limited on a global scale by the availability of land, water and energy," said Fred Davies, senior science advisor for the agency's bureau of food security.

"Food issues could become as politically destabilizing by 2050 as energy issues are today," he told a gathering at the North American agricultural journalists' meeting in Washington, DC, this week.

By mid-century, the world population would increase 30 percent to nine billion people, eventually calling for a 70 percent increase to meet demands in food, according to Davies.

Agricultural productivity, food security, food safety, the environment, health, nutrition and obesity - they are all interconnected, according to IANS.

With mid-income nations such as China, India, Brazil and the Philippines hosting 75 percent of the world's chronically poor, one in eight people worldwide also suffer from chronic undernourishment.

"But resource limitations would constrain global food systems. The increases currently projected for crop production from biotechnology, genetics, agronomics and horticulture would not be sufficient to meet food demand," he emphasized.

The ability to discover ways to keep pace with food demand has been curtailed by cutbacks in spending on research, he said.

"The U.S. agricultural productivity has averaged less than 1.2 percent per year between 1990 and 2007," he said.

Small-scale farmers around the world don't get to make use of new technologies that are developed, IANS reported.

"More efficient technologies and crops need to be developed. Equally important are better ways for applying these technologies locally for farmers," Davies said.