Complex sentence: Though these gardens were initially designed with the aim of testing the effects of radiation on plant life, research gradually turned towards using radiation to introduce beneficial mutations that could give plants useful characteristics, like increased resilience to adverse weather, or a faster growth rate.
Split into simpler sentences: Though these gardens were initially designed with the aim of testing the effects of radiation on plant life, research gradually turned towards using radiation to introduce beneficial mutations that could give plants useful characteristics. Such characteristics include increased resilience to adverse weather, or a faster growth rate.