From his past experiences, Mendel knew how to crosspollinate
plants and how the characteristics of peas
could be used in his studies. For his experiments,
Mendel selected only true-breeding strains and studied
only a few traits at a time. He grew his chosen plants
for two years to make sure he had a true-breeding strain
of peas. When he began crossing true-breeding strains,
Mendel made sure that the two parents differed only in
the few traits he had chosen. Scientists working before
Mendel failed in their similar experiments because they
did not use true-breeding strains and did not limit the
traits they were testing.
Mendel was methodical in recording and applying
mathematical analysis to his results. His careful
numerical analysis had never been done in truebreeding
experiments before and was an essential factor
in Mendel’s success.