Measurement of Short‐Term Root Growth by Prestaining with Neutral Red1

A root staining procedure is described for measuring root growth during short term treatment periods. The vital stain, neutral red chloride, was used to stain roots in vivo. White root growth occurring after the staining period was easily differentiated from the stained portion of the pretreated root system. The staining treatment did not significantly alter plant growth or root respiration rates. The neutral red was primarily confined to cell walls of the cortex for the short term studies reported. Use of this or similar staining techniques combined with image processing equipment promises to provide a suitable method for rapid, inexpensive, and quantitative measurements of root responses to short term treatments.