Seed germination rotating cylinder and seed germination machine

A seed germination machine, comprising a seed germination rotating cylinder, wherein the seed germination rotating cylinder comprises:

• a cylinder body;
• a seed germination chamber being defined in the cylinder body, wherein the seed germination chamber is configured to germinate seeds therein;
• a plurality of grooves being defined in the cylinder body, wherein each of the grooves is recessed from an outer surface of the cylinder body toward the chamber such that a plurality of protrusions are formed in the chamber at an inner surface of the cylinder body;
• wherein a plurality of openings are annularly defined in each of the protrusions at a top surface of each of the protrusions and communicated with each of the grooves;
• wherein a height difference is formed between a connection of each of the protrusions and the inner surface and the top surface of each of the protrusions;
• each of the protrusions is hollow, and a hollow portion of each of the protrusions is communicated with the plurality of openings and each of the grooves;
• wherein the plurality of openings are configured to discharge gas, which is generated in the seed germination chamber of the cylinder body during seed germination, out of the cylinder body through the plurality of openings, the hollow portion, and each of the grooves sequentially and prevent plants in the chamber from entering the hollow portion through the plurality of openings, and the protrusions are configured not to receive plants;
• at least one open slot is defined in an edge of an end portion of each of the protrusions, the at least one open slot penetrates a top wall of each of the protrusions and a side wall of each of the protrusions, and the at least one open slot is communicated with the hollow portion.