You cannot use a Wild Location card to build in a Farm Brewery.

This is specified on page 9:

• "Wild Location card: May be played as any Location card. This does not include the 2 Farm Breweries (see 'Farm Breweries')."

Additionally, under the "Farm Breweries" section on page 9:

• "You may only build in these locations using a Brewery Industry card or a Wild Industry card."

Summary

• Wild Location cards cannot be used to build in Farm Breweries.
• Only Brewery Industry cards or Wild Industry cards may be used to build in Farm Breweries.

Source: page 9.

Source: Core Rulebook (pp. 10, 11, 4, 9)