. Carnegie Institution of Washington publication. WILT OF CUCURBITS. 225 bell-jar. The first three vines were used as checks on the behavior of the fourth. The air under the bell-jars was quite moist and at 4 water stood in tiny beads on the margin of the leaves. At the end of 24 hours the under surface of the sprayed leaves was still wet in places especially that of the leaf on which the aphides were colonized. Some of the latter had migrated to other leaves. All were sucking the plant juices and for fear of mechanical injury I brushed off and destroyed most of them. None were observed o
. Carnegie Institution of Washington publication. WILT OF CUCURBITS. 225 bell-jar. The first three vines were used as checks on the behavior of the fourth. The air under the bell-jars was quite moist and at 4 water stood in tiny beads on the margin of the leaves. At the end of 24 hours the under surface of the sprayed leaves was still wet in places especially that of the leaf on which the aphides were colonized. Some of the latter had migrated to other leaves. All were sucking the plant juices and for fear of mechanical injury I brushed off and destroyed most of them. None were observed on the check vines. The bell-jars were removed and the plants exposed to the air for half an hour to dry off a little and then the jars were put back. This was done frequently during the experiment. The fourth day the vines were still healthy and the checks were free from aphides. Tube S, October 23, was inoculated from a very sticky potato culture (tube 8, October 17), which was inoculated from a single, small, white colony on a slant agar culture streaked September 2 7 from tube 1, September 17, which was inoculated from the interior of plant No. 2. (20.) Cucumber (check). Plant about 5 inches high with two well-developed leaves and one more coming, also two green cotyledons. The bacterial fluid was sprayed on the under sur- face of the two largest leaves and the plant was then put back under the bell-jar. The eight day after spraying, this vine was still healthy. It had grown an inch or two since October 25. It was still free from ants and aphides. Two days later it was healthy and growing rapidly. The twenty- third day the bell-jar was removed and not re- placed as the plant was beginning to be spindling although no trace of the disease had appeared. The thirty-fourth day the vine was still free from the disease but had remained spindling since the removal of the bell-jar. By the fifty-first day the plant had lost all its leaves and the tip of the stem had wilted. It was not
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Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1911
