DESICCATED NODULES AS A SOURCE OF THE ROOT-NODULE ORGANISM

An Abstract

J. K. Wilson1

Nodules of a large number of legumes have been employed inthis study. They may be collected whenever found and held for fu-ture work. The nodules are washed free of soil and allowed to dryspontaneously, then stored. Such nodules have been a source of theroot-nodule bacteria for an extended period of time. At least forone year the organism may be easily isolated. The desiccated nod-ule is placed in water. It will resume approximately its originalsize. This may take thirty minutes for nodules of certain legumesor several hours for others. After this soaking-up process thenodule may be handled as a fresh nodule. They have been desiccat-ed as far away as China and sent to our laboratory, where the root-nodule bacteria was isolated by following the above procedure. Also,nodules were collected in the summer time and employed in class workduring the following spring. However, because of the smallness ofthe dried specimens, students destroy too much desiccated materialto make this method very servicable for laboratory exercises.

•"•Cornell University, Ithaca, New York.

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