sunset crop

A type of agricultural crop that is not expected to be commercially viable much longer.

Japanese Meaning

商業的に採算が取れなくなると予想される農作物の種類 / 近い将来、経済的に維持できなくなると見込まれる農作物

The farmer reluctantly planted the sunset crop for one last season, knowing buyers would likely vanish next year.

農家は、市場価値が失われつつある作物をあと一シーズンだけ渋々植えた。来年には買い手がいなくなるだろうと分かっていた。

Sense（1）

A type of agricultural crop that is not expected to be commercially viable much longer.

It would seem therefore that the rubber tree need no longer be considered as a "sunset crop"

sunset crops

（ plural ）