. Bacteria in relation to plant diseases. Bacteriology; Plant diseases. INFECTION THROUGH NECTARIES. 55 have studied this phase of the subject experimentally. In iSgijWaite sprayed pure cultures of Bacillus amylovorus upon pear-flowers and obtained many cases of blossom-blight. This was studied in all stages, from the first incipient multiplication of the bacteria in the nectar to the destruction of the flower and the passage of the bacteria down the pedicel into the stem. By protecting the flowers from the visits of insects by means of mosquito- netting, this artificially induced blossom-blig
. Bacteria in relation to plant diseases. Bacteriology; Plant diseases. INFECTION THROUGH NECTARIES. 55 have studied this phase of the subject experimentally. In iSgijWaite sprayed pure cultures of Bacillus amylovorus upon pear-flowers and obtained many cases of blossom-blight. This was studied in all stages, from the first incipient multiplication of the bacteria in the nectar to the destruction of the flower and the passage of the bacteria down the pedicel into the stem. By protecting the flowers from the visits of insects by means of mosquito- netting, this artificially induced blossom-blight was restricted to certain branches. This particular experiment was made in an orchard in Kent County, Maryland, which was remarkably free from natural blight and had been for years. In other experiments, not in that orchard, Mr. Waite again produced blossom-blight on certain clusters of pear- blossoms by infecting the floral nectaries and by allowing the bees to have free access to these blossoms he succeeded through their agency in transmitting blight to other flower- clusters on the same tree. One of these experiments took place on the grounds of the United States Department of Agriculture, an isolated tree previously free from blight being used for this purpose. Bees were observed to visit the infected flowers and, subsequently, flowers on other clusters, which flowers afterwards blighted. Some of these bees were caught, their mouth parts excised, and cultures made therefrom by means of poured-plates in Petri dishes. Colonies obtained in this way closely resembled the pear-blight organism, and inocu- lations therefrom produced the disease in sound pear-shoots, thus demonstrating beyond dis- pute the actual presence of the pear-blight organism on the mouth parts of the suspected Dees. Everybody connected with the plant pathological work of the U. S. Department of Agriculture at that time had knowledge of these results. The writer, among others, saw all of the experiments d
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