A Flow-Through Testing Procedure with Duckweed (Lemna minor L.),

摘要

Lemna minor is one of the smallest flowering plants. Because of its floating habit,ease of culture,and small size it is well adapted for laboratory investigations. Procedures for flow-through tests were developed. Testing procedures were developed with this apparatus. By using the techniques described here,the effects of nutrients or toxicants,singly or in combination,can be determined in several concentrations with several replicates of each. Responses which can be measured include changes in growth rate,changes in death rate,changes in timing of division of colonies,color changes,changes in variability,and modification of the flowering response. Emphasis here is on changes in growth rate determined either by daily frond counts or by final frond numbers.