丰宁满族自治县波罗诺镇波西村第三生产组，利用位于塞北山区气候冷凉适于繁育杂交蕃茄种的优势，1995年组织了28个科技示范户承担了承德市蔬菜所蕃茄杂交繁种任务（25亩），平均亩产种子15．2公斤，亩纯收入3210元。1996年扩大到70户，科技示范户承包蕃茄杂交繁种55亩，平均亩 Fengning Manchu Autonomous County of Polonnuo Poseidon village third production group, the use of mountainous areas in northern Saibei cold climate suitable for breeding hybrid tomato advantages, in 1995 organized 28 science and technology demonstration households bear Chengde City, tomato hybrid breeding Mission (25 acres), the average yield of 15.2 kg per mu, net income 3210 yuan. 1996 expanded to 70 households, science and technology demonstration contract contracted tomato hybrid 55 mus, the average mu