A Pure-Breeding Flowering Plant with a Long Stem and Small

A pure-breeding flowering plant with a long stem and small leaves was crossed to a pure-breeding individual of the same species that has a short stem and large leaves.The F₁ is comprised entirely of individuals with long stems and large leaves.When these F₁ individuals are testcrossed,they only produced about half as many individuals as expected.The phenotypic ratios were: 462 short stems and large leaves,450 long stems and small leaves,52 long stems and large leaves,and 50 short stems and small leaves.
These 1022 plants were further crossed to a tester,and many of them displayed semi-sterility,in particular:
of the 462 plants with short stems and large leaves,362 were semisterile.
of the 450 plants with long stems and small leaves,90 were semisterile.
of the 52 plants with long stems and large leaves,40 were semisterile.
of the 50 plants with short stems and small leaves,10 were semisterile.
Provide a plausible,comprehensive genetic explanation for these results.