The chart above reflects the results of the Reuters / Ipsos Poll (the most recent being released on October 5th, with a 3 point margin of error). It shows the net approval (approval percentage minus disapproval percentage) of Donald Trump among rural voters.
In the first four months of his presidency, Trump had a net approval rating of 17 points (56% approval and 39% disapproval). That has slide downward dramatically since then. Currently, Trump has a net approval rating of 0 (47% approval and 47% disapproval).
This should worry Trump. Rural voters make up 15% of the electorate, and they voted big for him in the 2016 election. It was these rural voters in many states that helped him squeak out an electoral college win. If he loses their support, as he seems to be doing, I don't think he could be re-elected.
NOTE -- The white line is the actual poll results, and the red line shows the trend of those results.