Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Light and scanning electron micrographs of pollen germination in Cannabis sativa. (A) Pollen germination in water after 72 h showing germ tube formation at a 20% frequency. (B) Female inflorescence showing protruding receptive stigmas. The flower heads were excised and pollinated in vitro using pollen collected from a male flower. (C–F) Pollen germination and germ tube development on stigmatic papillae in situ. Arrows show pollen grains in (C,D) and germ tube growth in (E,F).
