agriculture alga amoeboid barley bean brassica bryophyte climate coleoptile conifer cone cotyledon digital object identifier dormancy ecology embryo epicotyl epigeal eranthis hyemalis fern flower flowering plant fruit fungus gametophyte gardening gemination germ gibberellin gymnosperm hydration hypha hypocotyl imbibition inbreeding light lily seed germination types malt marchantiophyta metabolism moss oil ovule oxygen physiology phytotoxicity plant pollen pollen tube pollination protein prothallium protonema quiescence radicle ranunculaceae resting spore seed seedling self-incompatibility in plants soil species sperm spore sporeling sprouting starch stigma sunflower temperature thallus vernalization water wikibooks zoospore zygospore