Due to the fact that sexual organisms exchange and mix their genetic material when they breed, their traits can be more easily manipulated artificially. Under the assumption that Trichoderma reesei was asexual, scientists looking to improve the fungus were instead limited to techniques like dosing the fungus with radiation or chemicals in order to alter its genetic profile. But that process only created random or unpredictable mutations.

But for the first time since its discovery 50 years ago, scientists can now make the fungus have sex.

Past studies have shown that Trichoderma reesei is genetically identical to another species of fungus, Hypocrea jecorina, which it so happens is capable of sexual reproduction. The primary difference between the two organisms was that Hypocrea jecorina seemed capable of assuming both the male and female roles, whereas Trichoderma reesei seemed only capable of assuming the male role.

So scientists got a novel idea: Why not breed the male-oriented Trichoderma with a female-oriented Hypocrea? The result was a successful mating– the Trichoderma lured into having sex could now be artificially selected for their advantageous genetic traits.

Found by David Guaraglia.