Distribution of manganese in the pea seed in relation to marsh spot

Publisher Website
Google Scholar
Abstract
1. An outline of recent investigations on the cause of marsh spot in pea seeds indicates that the disease is caused by a deficiency of available manganese in the soil.2. The symptoms of the disease are very briefly described.3. The methods of analysis used by the writers for determining the amounts of manganese in whole peas and in different parts of peas are described.4. As no loss of manganese was found to result from soaking the peas in water for 24 hr., soaked peas were used for dissection in preference to dry peas.5. Referring to the diseased peas, the highest level of manganese was found in the peripheral tissues of the cotyledons, followed by the germ and seed-coat. Only slight traces of manganese were found in the healthy and in the necrotic tissue from the centre of the cotyledons. All parts of the healthy seed were richer in manganese than the corresponding parts of the diseased sample. In addition, the order of distribution was different; notably in that the tissue from the centre of the cotyledon contained a higher level than the seed-coat, and the germ a higher level than the outer layers of the cotyledon.6. A given weight of small peas proved to contain less manganese than the same weight of large peas selected from the diseased sample. The reverse was found to be true for similar size groups selected from the healthy sample. These differences in the manganese content of size groups suggest that peas of uniform size should be selected for analysis when the relative manganese levels of different samples are to be tested.7. It is suggested that migration of cell contents from the necrotic tissue of diseased peas may partly account for the differences in manganese content of healthy and diseased peas.

This publication has 9 references indexed in Scilit: