– Vernon Hugh Bowman seems comfortable with the old way of doing things, right down to the rotary-dial telephone he said he was using in a conference call with reporters.

But the 75-year-old Indiana farmer figured out a way to benefit from a high-technology product, soybeans that are resistant to weedkillers, without always paying the high price that such genetically engineered seeds typically bring. In so doing, he ignited a legal fight with seed-giant Monsanto Co. that has now come before the Supreme Court, with argument taking place Tuesday.

The court case poses the question of whether Bowman’s actions violated the patent rights held by Monsanto, which developed soybean and other seeds that survive when farmers spray their fields with the company’s Roundup brand weedkiller. The seeds dominate American agriculture, including in Indiana where more than 90 percent of soybeans are Roundup Ready.

Monsanto has attracted a bushel of researchers, universities and other agribusiness concerns to its side because they fear a decision in favor of Bowman would leave their own technological innovations open to poaching.

The Obama administration also backs Monsanto, having earlier urged the court to stay out of the case because of the potential for far-reaching implications for patents involving DNA molecules, nanotechnologies and other self-replicating technologies.

Monsanto’s opponents argue that the company has tried to use patent law to control the supply of seeds for soybeans, corn, cotton, canola, sugar beets and alfalfa. The result has been a dramatic rise in seed prices and reduced options for farmers, according to the Center for Food Safety.

The group opposes the spread of genetically engineered crops and says their benefits have been grossly overstated.

“It has become extremely difficult for farmers to find high-quality conventional seeds,” said Bill Freese, the center’s science policy analyst.

Monsanto says the success of its seeds is proof of their value. By and large, “farmers appreciate what we do,” David Snively, Monsanto’s top lawyer, said in an interview with the Associated Press.

The Supreme Court will grapple with the limit of Monsanto’s patent rights, whether they stop with the sale of the first crop of beans, or extend to each new crop soybean farmers grow that has the gene modification that allows it to withstand the application of weedkiller.