dysgenesic

Of, pertaining to, or causing dysgenesis.

Tending to stunt to interfere with normal healthy development.

Polymorphism under Dysgenesic Conditions. The variations manifested by bacteria are still more curious when the latter are placed under conditions unfavorable to their development.

At the same time social change without corresponding environmental changes in other spheres turns itself on to dysgenesic trends.

Infertile when crossed with a similar hybrid but marginally fertile when crossed with one of the parent species.

But the degree of fertility of these crossings varies greatly in different species, for while some are perfectly fertile (eugenesic), the progeny of others will rarely breed except with a mate belonging to one of the original species (paragenesic), whiles in other cases the hybrids produced are wholly infertile among themselves, and scarcely fertile with either of the parent species (dysgenesic), or wholly infertile (agenesic).

Fecundation is […] dysgenesic when the hybrids, although mutually sterile, are fecund when crossed with an individual of one or the other of the parent races;

Involving reproduction by couples of different races, believed to lead to inferior offspring.

He would encourage by bonuses, eugenic and discourage by fines dysgenesic marriages among his employees.

Our whole urban and industrial life is avowedly dysgenesic.

Tending to promote childlessness.

While waiting for separate colleges to become coeducational, as they eventually will, their present dysgenesic tendency can probably be reduced by the gradual introduction of men teachers into the women's colleges.

[…] conditions is not wholly unfavourable or dysgenesic, and it is to be remarked that the decline in rural population has not been accompanied by any pro rata falling off in agricultural productivity.