Hebrew translation: (from MFA site for this poster)

"Buy local products" was the commercial slogan of the Land of Israel in the 1930s and 1940s. The flooding of local markets with fresh farm produce from neighboring countries, and the import of industrial goods from Europe, obligated the Jewish community in the Land of Israel to defend its fledgling agriculture and industry. (1940s)

http://www.mfa.gov.il/MFA/History/Modern+History/Centenary+of+Zionism/Im...