. California plant diseases. Plant diseases. 1124 UNIVERSITY OP CALIFORNIA EXPERIMENT STATION. The fungus is not actively parasitic and it has been found difficult to infect lemons with its spores save when they are injured or bruised in some way. They also require considerable moisture for infection. Experiments have shown that almost all the infection takes place at the stem end of the lemon where it is cut from the tree, and practically all, it is probable, in the washing water, except in the case of fruit allowed to stand out in the rain for some time, when infection may take place. Cotton
. California plant diseases. Plant diseases. 1124 UNIVERSITY OP CALIFORNIA EXPERIMENT STATION. The fungus is not actively parasitic and it has been found difficult to infect lemons with its spores save when they are injured or bruised in some way. They also require considerable moisture for infection. Experiments have shown that almost all the infection takes place at the stem end of the lemon where it is cut from the tree, and practically all, it is probable, in the washing water, except in the case of fruit allowed to stand out in the rain for some time, when infection may take place. Cottony mold sometimes develops to a considerable extent in packing houses where the fruit is being washed in bluestone solution to prevent brown rot, from which fact it appears that a strength of this substance which kills brown rot spores does not kill those of the cottony fungus. Laboratory tests have shown this to be a fact. The control of cottony rot, therefore, depends upon either using the germicide stronger than that used for brown rot or finding means for preventing the development of the fun- gus in the orchard. Along the former line we may say that it is not safe to use bluestone in the wash water much stronger than it is now being used in many houses for brown rot control; a strength of 1/50 of one per cent, or about 1J pounds of bluestone to 1,000 gallons of water. This would mean putting in about the quantity of bluestone stated into a 1,000- gallon tank in the morning and fortifying this with about one pound more in the afternoon, after considerable wash water has entered the tank. The question of the strength of bluestone in lemon wash water depends to a large extent upon the quality of the water used as to its alkali content, since the alkali salts neutralize the copper sulphate. This whole question of disinfecting lemon wash water is now being investigated at the Whittier Laboratory. In regard to orchard control of this trouble, we may say that the cot- tony mold ha
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectplantdi, bookyear1911
