Timing of germination in the subtropical chinese tree Castanopsis farqesii

Timing of germination in the subtropical chinesetree Castanopsis fargesii

ＴｉｍｉｎｇｏｆｇｅｒｍｉｎａｔｉｏｎｉｎｔｈｅｓｕｂｔｒｏｐｉｃａｌｃｈｉｎｅｓｅｔｒｅｅＣａｓｔａｎｏｐｓｉｓｆａｒｇｅｓｉｉＪ．Ｈ．Ｃ．Ｃｏｒｎｅｌｉｓｓｅｎ，ＺｈｏｎｇＺｈａｎｇｃｈｅｎｇ，Ｍ．Ｊ．Ａ．Ｗｅｒｇｅｒ（ＤｅｐａｒｔｍｅｎｔｏｆＢ...

The timing of germination was studied in the subtropical chinese chestnut tree Castanopsis far-gesii Franch.It has fruits with one big,water-rich seed,which are shed in autumn.Under natural con-ditions germination is delayed until spring,although locally the winter is mild and humid.Winter stor-age of chestnuts at relatively low temperture or water availability resulted in later germination aftersowins in spring.smaller chestnuts serminated significantly earlier than bigger ones,as correspondingwith their higher ratio between contact area chestnut-subetrate and chestnut size.Early germinationwas associated with comparatively high embiyo water contents after winter storage.Germination couldbe enforced shortly after ripening by exposure of chestnuts to higher than outdoor temperatures at good water availability.It was concluded that delayed germination in Castanopsis fargesii is not due to truedormancy.Instead,the chestnuts winter in nature in a quiescent state,that means at changeable,lowlevels of metabolic activity due to low temperatures and/or water availability