关键词: 丙烷脒, 丙烷脒, 杀菌剂, 防治效果, 番茄灰霉病

Abstract: For the purpose of knowing the influences of different cultivation environment on Maryland tobacco and suggesting scientific fertilization ways, an experiment was conducted in two distinct areas of applying different amount of manuring, potassium to nitrogen ratio and nitrogen conformation on Maryland plants. The results showed that the amount of nitrogen application had a most influence on yield and nitrogen form did second. Furthermore, nitrate nitrogen conduced to reduce nicotine content and increase potassium content. It was not obvious to improve the surface quality and potassium content of Maryland tobacco leaves by increasing potash fertilization at alkalescent soil or over 120kg/hm2 of nitrogen application. Thus, to retain the characteristic of Maryland tobacco, the plants should be grown on feasible soil with pH＜7.5. The appropriate amount of nitrogen application should be 120~150kg/hm2 in which 50%~75% of nitrate nitrogen account for. potassium to nitrogen ratio could be confined to less than 3:1, and a lower ratio of 1.5:1 would be reasonable if potassium content in soil is not fairly low.