The amount of grain produced by each plant is being compared to the single seed from which it grew. Ellipsis is used here to shorten the phrases but they can be written out. Alternate translation: "Some plants bore thirty times as much as the seed that the man had planted, some produced sixty times as much grain, and some produced a hundred times as much grain" (See: [[rc://en/ta/man/translate/figs-ellipsis]])