Page 135 - Pharmacognosy 2 PG303

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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