Based on prior knowledge, the number of stems (NLP) in soybean cultivars can vary depending on the yield. In general, a higher number of stems tends to result in a higher yield. However, there may be some variations and specific ranges that could affect the yield.

Considering these factors, we can assume the following relationship between the feature NLP and the grain yield of the soybean cultivar:

- Low yield: NLP values ranging from 0 to 50 (inclusive) could be considered as typical for soybean cultivars with low grain yield.
- High yield: NLP values ranging from 51 to 100 (inclusive) could be considered as typical for soybean cultivars with high grain yield.

Based on this analysis, here's the dictionary with the possible values of feature NLP for each target class:

```json
{
	"low": [0.0, 10.0, 20.0, 30.0, 40.0],
	"high": [65.0, 75.0, 85.0, 95.0, 100.0]
}
```

Please note that these values are just approximations and may vary depending on the specific soybean cultivar and other environmental factors.