Based on prior knowledge, we can analyze the relationship between the feature "plant height (cm)" (IFP) and the task of predicting the grain yield of the soybean cultivar as low or high. Here are some possible ways to analyze this relationship:

1. Higher plant height (IFP) can be associated with high grain yield: It is generally observed that taller plants have a higher potential for yield due to larger canopy size and increased capacity for photosynthesis. Therefore, it is likely that high IFP values could indicate a high grain yield.

2. Lower plant height (IFP) can be associated with low grain yield: Conversely, shorter plant height may indicate stunting, nutrient deficiencies, or other factors that could negatively impact the yield potential. Therefore, it is possible that low IFP values could indicate a low grain yield.

3. Optimal plant height (IFP) range: There may be an optimal range of plant height (IFP) that is associated with the highest grain yield. This range could vary depending on the specific soybean cultivar and environmental conditions.

Now, let's create a dictionary that includes 5 typical IFP values for each target class ('low' and 'high'):

```json
{
	"low": [25.6, 27.1, 26.8, 28.2, 24.9],
	"high": [32.5, 31.7, 33.2, 34.1, 30.8]
}
```

Please note that the specific values provided in the dictionary are just examples and may not represent the actual relationship between IFP and the target classes. It is important to perform a thorough analysis and consult relevant literature or data to determine the appropriate ranges and values for the specific soybean cultivar and context.