In the past, the aquatic pteridophyte Marsilea quadrifolia L. was considered as a weed in paddy fields of southern Europe. The systematic use of herbicides as a crucial component of intensive agronomic approach has led to a dramatic decline in M. quadrifolia populations in European countries, mostly in the Mediterranean area. However, the introduction in recent years of sustainable rice cultivation practices has allowed partial recovery. We present here the results of a research aimed at analyzing the effects of farming typologies in respect to M. quadrifolia growth in the Po Valley area. After having transplanted M. quadrifolia swards in rice fields belonging to different farming systems, we monitored its growth and diffusion. Our results showed that M. quadrifolia has higher vegetative performance in organic farms, even though it can survive in conventional fields with reduced herbicide supply. Differences in water chemistry have limited effects on M. quadrifolia performance, because of its wide ecological amplitude. The shady conditions provided by rice canopy create micro-habitats suitable for M. quadrifolia growth. Cultivating M. quadrifolia in organic rice farms represents an important opportunity for preserving this endangered species in areas of intensive agriculture. This can, meanwhile, represent a valid opportunity to combine nature conservation and productivity offering a new possible income for farmers.

过去，水生蕨类植物Marsilea quadrifolia L.被认为是欧洲南部稻田中的杂草。系统地使用除草剂作为集约化农艺方法的重要组成部分，已导致欧洲国家（主要是地中海地区）的四叶松线虫种群急剧减少。但是，近年来引入的可持续水稻种植方法已使部分恢复。我们在这里介绍一项旨在分析农业类型对坡地谷地区四叶分枝杆菌生长的影响的研究结果。移植后四叶猴在属于不同耕作制度的稻田中，我们监测了它的生长和扩散。我们的研究结果表明，尽管四叶松线虫可以在常规田间除草剂供应减少的情况下生存，但在有机农场中却具有较高的营养价值。由于其宽的生态幅度，水化学上的差异对四叉螺旋藻的性能影响有限。水稻冠层提供的阴凉条件创造了适合四生分枝杆菌生长的微生境。栽培四叶李有机稻田中的稻草提供了在集约化农业地区保护这一濒危物种的重要机会。同时，这可以代表自然保护与生产力相结合的有效机会，为农民带来新的收入。