最大或然数法在光合细菌计数中的应用及效果研究

1引言光合细菌(photosynthetic bacteria,PSB)是能进行不放氧光合作用的一大类细菌的总称,属水圈微生物,广泛分布于地球生物圈,无论江、河、湖、海,水田、旱地都有存在3].光合细菌在水体自净、调节微生态平衡、促进动植物生长、增加产量和提高产品质量、防病、固氮等方面具有重要作用3,22].近年来,光合细菌菌剂在水产养殖、家畜养殖、污水处理及植物生产上的应用日益广泛3,13,19,27,28,31],相继推出多种产品,包括单菌菌剂、复合菌剂,剂型上有液体菌剂、浓缩菌剂和固体菌剂(粉剂)等20].为保证产品质量和应用效果,有必要对光合细菌菌剂…

Application effect of most probable number(MPN)method in photosynthetic bacteria counting

The application of most probable number(MPN)method in counting the numbers of photosynthetic bacteria(PSB)showed that this method was suitable for PSB counting under illumination and anaerobic condition,which remedied the shortages of other methods.With this method,the sensitivity and accuracy of the counting could be enhanced when more replicated tubes and lower dilution times for fewer bacteria samples were applied.When PSB were not dominant in soil and water,MPN method could be used instead of other methods.PSB agent could only survive 69 days,and not be dominant in the environment in a long term.Its application time and oxygen level affect the numbers of PSB significantly,which were the largest in a short application time and under anaerobic condition.