Page 135 - Pharmacognosy 2 PG303 (1)
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Pharmacognosy-2 (PG303)                              Level 2                Clinical Pharmacy-Pharm D

                     pale- colored remains of the sphacelia stage. This hard structure is dark purplish- brown
                     and known as (sclerotium).
                 5-  When the ripened rye grains fall, the sclerotia fall with them and remain in the ground
                     through the winter.
                 6-  In  the  following  spring,  each  sclerotium  germinates  and  sends  out  several  upright
                     cylindrical stalks or stromata, each about 10- 20 mm. long. The apex of each stroma swells
                     into a spherical head 2 mm in diameter, in which are embedded a number of flask- shaped
                     cavities named perithecia.
                 7-  Each  perithecium  contains  numerous  elongated  asci  or  sporangia  in  each  of  which  8
                     filiform ascospores are formed.
                 8-  The ascospores escape from a pore in the apex of the ascus, fall on the ground and develop
                     into small branching threads bearing numerous small spores.
                 9-  The spores are carried out by the wind to the ovaries of the new crop of rye, which will
                     now be at the flowering stage.















































              Macroscopical Characters
                     Shape and size: fusiform or subcylindrical, up to 45 mm long and 7 mm thick. Outer
              surface: dark violet- brown to nearly black, with longitudinal furrows. It may bear small transverse
              cracks and pale remains of sphacelia at the apex. fracture: short with whitish central zone and
              darker radiating lines from the center. Odor: characteristic and disagreeable being intensified on
              trituration with caustic alkali. Taste: oily, characteristic, and disagreeable.

              Microscopical Characters


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