CHE REFERENCE LIBRARY - ZetaTalk

PROPAG.4TlON BY MEANS OF SEEDS AND SPORES 21conditions of moisture and temperature can be maintained.Seeds sown 011 a moist surface a.nd covered with a glasspresent an interesting study. They may have difficulty ingetting a foothold, and they present peculiar reactions tolight.It is well knvwn, on t.he other hand, that some seeds willnot germinate, or will at lea*st appear unevenly, if subjectedto sunlight. At least some of the delphiniums, papavers andadonises germinate very imperfectly, ii” at a.11, in direct light.It is always advisable to keep germinating seeds in shade orpartial darkness, especially a.s there is nothing to be gained byexposing them. Of course, the soil itself is sufiicient protectionif the seeds are covered.Xegemr inationIt is a common statement that seeds can never revive ifallowed to become thoroughly dry after they have begun tosprout. This is an error. Wheat, oats, buckwheat, maize,pea, onion, ~%sh and other seeds have been tested in thisregard, and they are found to reger;cir\ate readily, even ifallowed to become thoroughly dry and brittle a&r cproutingis well progressed. They will even regerminate severaltimes.Kheat, peas and other seeds have been carried through asma.ny as seven germinations after the radicle had grown a halfinch or more and the seeds had been sufficiently dried in eachtrial to render them fit for grinding.Delayed germinationn~‘ AWe noted in Chapter I that most seeds have a natural periodof dorma,ncy. This period may be considerably shortened orlengthened in many cases by the treatment to which the seedsare sub jetted.