. Cyclopedia of farm crops. Farm produce; Agriculture. LEGUMES LEGUMES 393 form. These two forms of the organism are now generally recognized. The minute motile form is about 1 !>. long by m in width (/i is a micron or TTrVff of a millimeter). This is the form which enters the root-hairs, multiplies and travels in the strand-like zoiigloea into the root where the gall or nodule is stimulated. Because of this motile. Fig. 591. Root nodules. Black medic (Jfedtcajo iiip«iina). Two and one-half times natural size. form, Moore has recently changed the name to Pseudomonas radicicola, though t
. Cyclopedia of farm crops. Farm produce; Agriculture. LEGUMES LEGUMES 393 form. These two forms of the organism are now generally recognized. The minute motile form is about 1 !>. long by m in width (/i is a micron or TTrVff of a millimeter). This is the form which enters the root-hairs, multiplies and travels in the strand-like zoiigloea into the root where the gall or nodule is stimulated. Because of this motile. Fig. 591. Root nodules. Black medic (Jfedtcajo iiip«iina). Two and one-half times natural size. form, Moore has recently changed the name to Pseudomonas radicicola, though the relation of the cilia to the organism is not very clearly known, in consequence of which there may be tainty as to the appropriateness of this name. The larger rod-like form is /j. to 5 ij- long by ij. to M in width. These are the " ; They are usually rod-like, but often branched forms occur which are Y- or X-shaped, or even sometimes more complicated in form. These bacteroids or rods which are found in such large numbers in the old tubercles are abnormal, or involution forms. It is thought by some that the Y and X forms are the result of branching, perhaps a false branching caused by division of the rods, several rods being held together within a gelatinous sheath. It is well known that these " bacteroids," or dead invo- lution forms of the organism, are rich in proteid matter. The host plant, which is the legume, has the power of dissolving these and of absorbing the nitrogenous matter from the tubercles and using it as food. 'When the tubercles die, some of them are emptied into the soil, and the minute motile form also escapes, thus keeping the soil inoculated with this organism where legumes are growing. miy legumes are valuable in soil-enrichment. It has long been known that certain leguminous crops like peas, clovers and alfalfa, were better crops for the enrichment of the land in nitrogenous food when plowed und
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