Based on the given feature "Season" and the task of predicting the grain yield of the soybean cultivar as low or high, we can analyze the relationship between the feature and target by looking at prior knowledge about soybean cultivation.

Analysis:
1. Typically, soybean cultivation is done during specific seasons of the year. The timing of seasons may vary based on the geographical location and specific climate patterns. 

2. In general, soybean cultivation can be categorized into two main seasons:
   - Season 1: This could represent the main growing season for soybeans, which includes spring and summer.
   - Season 2: This could represent a secondary growing season for soybeans, which includes fall and winter.

Based on this analysis, we can create a dictionary that captures the relationship between the "Season" feature and the target variable "grain yield".

```json
{
	"low": [1.0, 1.0, 1.0, 2.0, 2.0],  
	"high": [2.0, 1.0, 2.0, 1.0, 1.0]  
}
```
In this dictionary, we include 5 typical values for each target class. The target class "low" is associated with the feature values [1.0, 1.0, 1.0, 2.0, 2.0], while the target class "high" is associated with the feature values [2.0, 1.0, 2.0, 1.0, 1.0].

Please note that these values are just examples and might vary depending on the specific soybean cultivar and the region in which it is grown.