ローソンヒノキ×サワラの種間雑種にみられる致死性の黄子苗

概要

論文の詳細を見る
As a part of the work on interspecific crossabilities in the genus Chamaecyparis, hybridizations between C.lawsoniana (A.MURR.) PARL. as the female parent and some other Chamaecyparis species as the male parents were made artificially in 1975 and 1976. In the hybridization between C.lawsoniana and C.pisifera (S.et Z.) ENDL., about 53,000 seeds (empty and full seeds) were obtained, and 321 hybrid seedlings were produced. Twenty-nine of thirty-four hybrid seedlings produced in 1975 (85.3 percent) had yellow cotyledons and pale pink hypocotyls, whereas five others had normal green cotyledons. In 1976,247 of 287 hybrid seedlings (86.1 percent) had yellow cotyledons while others were normal. These yellow seedlings, called xantha, gradually shrank and died within several weeks of germinating, and none of them changed into normal green seedlings. The xantha seedlings were in high frequency in all of the mating combinations in the crosses between C.lawsoniana and C.pisifera, whereas they hardly ever were found in the crosses between C.lawsoniana and C.obtusa and in the crosses within the maternal species. It seems to be a rare occurrence in forest trees for hybrid inviability, one of the barriers of reproductive isolation between species, to be so remarkably shown among seedlings derived from interspecific crosses with relatively high seed fertility.
日本森林学会の論文
1981-02-25