Based on my prior knowledge, the relationship between the number of stems (NLP) and the grain yield of soybean cultivar is as follows:

1. Low Yield: Generally, a lower number of stems can indicate a low yield. In this case, lower values of NLP would be associated with low yields.

2. High Yield: Conversely, a higher number of stems can suggest a higher yield. Therefore, higher values of NLP would be more likely to be associated with high yields.

Using this information, I will generate a dictionary that provides possible values of NLP for each target class ('low' and 'high'), including five typical NLP values for each class.

```json
{
	"low": [1.5, 2.0, 2.5, 3.0, 3.5],
	"high": [5.0, 5.5, 6.0, 6.5, 7.0]
}
```

Please note that the values provided are hypothetical examples and may not reflect the actual relationship between NLP and grain yield for soybean cultivars.