Gertrude Sellards Pearson who combined with her late husband to rate among the top benefactors in Kansas University history died at the age of 88 in a Tucson, Ariz., hospital. She and her husband, Joseph R., who died in 1955, had given more than $700,000 to KU, most of it to provide housing for students. The Pearsons had been engaged in railroading, real estate and oil interests and called Corsicana, Texas, their home.