How are bacterial spores different from plant spores?

They differ in function.

1) Bacteria need spores not for reproduction, but for waiting out unfavorable conditions. In this case, the cell is severely dehydrated, which allows it to temporarily suspend its vital activity, and is covered with a dense membrane. In this state, the cell can withstand many unfavorable conditions, except for ultraviolet radiation, and some are able to survive in this form for centuries, therefore, spore-forming pathogenic bacteria are especially dangerous.

2) Plants use spores for reproduction. They are lightweight, easily spread by wind or with the help of animals.