A Cornell University geneticist, Ray Wu, the pioneer in genetic engineering who developed pest-, drought-, and salinity-resistant rice strains poised for widespread use throughout the world, died Feb. 10 in Ithaca, N.Y. He was 79. The new strains have the potential to sharply increase the supply of rice, which is the staple food for more than half the world’s population.

“Where rice is grown, everyone knows Ray Wu,” a Cornell geneticist, Susan McCouch, said.

In 1970, Wu developed the first method for determining the nucleotide sequence of DNA, then turned to methods of transferring foreign genes into rice.

In one study, he inserted into rice a potato gene that produces a protein that interferes with the digestive process of the pink stem borer, a common rice pest.

Another study increased the tolerance of rice for drought, salt, and heat by introducing the bacterial gene for a sugar called trehalose. The sugar is produced only when the rice plants actually need it.

Wu said the technology could easily be extended to a variety of other grain crops to improve their output.

Wu founded a program that brought hundreds of top Chinese students to America for graduate study. He also helped establish national research institutes in Taiwan and mainland China.

Ray Jui Wu was born Aug. 14, 1928, in the city then called Peking, now Beijing. At the urging of his father, a famed microbiologist who was among the first to propose protein folding, Wu came to America for his education in 1948. He earned a bachelor’s degree in chemistry from the University of Alabama in 1950 and a doctorate in biochemistry from the University of Pennsylvania in 1955. He worked at Penn, the Massachusetts Institute of Technology, and the Medical Research Council Laboratory in Cambridge, England, before joining Cornell in 1966.