Molybdenum Fertilizers

Several molybdenum sources can be used to prevent or alleviate molybdenum deficiency in crop plants (Table 13.4). These sources vary considerably in their solubility and in molybdenum content, and their effectiveness often depends primarily on the method of application, plant requirements, and on various soil factors (87). The relative solubilities of some molybdenum fertilizers are as follows:

sodium molybdate > ammonium molybdate > molybdic acid > molybdenum trioxide > molybdenum sulfide (114).

Molybdenum frits can also be used to supply Mo, but because of their limited solubility, they must be ground finely to be effective (89). Because of the low plant requirement for molybdenum and its mobility in plant tissues, several methods of molybdenum application are possible including soil application, foliar fertilization, and seed treatment with various molybdenum sources.