低产品种 meaning in English

low-yield variety

What myr has pointed out in china is that many of the present day recommendations are outdated because they were either obtained with low inputs ( low yielding varieties , low fertilizer use , low plant populations , etc . ) or imbalanced fertilization
中国的最高产量研究指出，许多现行的推荐已过时，因其或在低投入（低产品种、低施肥量、低种植密度等）或在不平衡施肥的情况下获得。