Abstract
1) This paper reports the results of experiments concerning serological studies on barley stripe mosaic disease. Expressed juice of diseased plants, including barley (variety Moravia), wheat (variety Norin No. 29), and sweet corn (variety Golden Bantam), was centrifuged at 3, 500rpm for 30minutes; supernatantfluid was frozen, kept overnight, and thawed; then it was again centrifuged at 3, 500rpm for 30 minutes. The clarified fluid was purified by salting-out with ammonium sulfate at two-fifths saturation, or by differential centrifugation. In either procedure, the final virus preparation was concentrated into one-tenth volume of the original juice. Rabbits were injected intravenously with such immunogen at 3 day intervals, giving 50-60ml in total, until antibody response became sufficient to be used for serological reactions; the animals were bled about ten days after the last injection.
2) Positive reaction was usually observed against clarified sap from both diseased and healthy plants, when antisera prepared with the immunogen purified by the procedure of salting-out was used.
3) By injection into rabbits of the immunogen from diseased barley purified by differential centrifugation, specific antisera were obtained which react not against the juice of healthy plant, but against that of diseased plants. On the other hand, positive reaction was obtained with both diseased and healthy plant juices, when use was made of the antisera prepared by the immunogen from diseased wheat and sweet corn purified by differential centrifugation.
4) Regarding the normal proteins contained in both diseased and healthy plants, it was found there were some similarities not between those of barley and sweet corn, but between barley and wheat as well as between wheat and sweet corn.
5) Partially purified virus preparation from diseased barley plant was secured by salting-out with ammonium sulfate, while more purified one was obtained by differential centrifugation.
6) The antisera prepared as mentioned adove, became reacting specifically only with expressed juices of diseased plants or purified virus preparations, when they were absorbed by homologous healthy plant juices,
