Parentage Analysis of Dongfang No.2, a Hybrid of a Female Gametophyte Clone of Laminaria japonica (Laminariales, Phaeophyta) and a Male Clone of L. longissima  

作　　者：YANG Guanpin LIAO Meijie LI Xiaojie CONG Yizhou QU Shancun WANG Tongyong 

机构地区：[1]College of Marine Life Sciences, Ocean University of China, Qingdao 266003, P. R. China [2]Shandong Oriental Ocean Sci-Tec Co., Ltd., Yantai 264003, P R. China [3]Wendeng Fishery Technique Popularization Station of Shandong Province, Wendeng 264400, P R. China

出　　处：《Journal of Ocean University of China》2008年第2期193-198,共6页中国海洋大学学报（英文版）

摘　　要：The cultivation of the first filial generation of monoploid gametophyte clones of different Laminaria species (hybrid Laminaria) is an effective way of utilizing heterozygous vigor (heterosis). A female gametophyte clone of L. japonica and a male gametophyte clone of L. longissima were hybridized, generating Dongfang No.2 hybrid Laminaria. The parentage of this hybrid Laminaria was determined using AFLP of total DNA, SNP of the ITS region of ribosomal RNA transcription unit and microsatellite DNA variation at two loci. In addition to 167 AFLP bands shared by Dongfang No.2, L. japonica and L. longissima, Dongfang No.2 hybrid Laminaria shared another 70 and 55 bands with L. japonica and L. longissima, respectively, which were obviously more than 11 bands shared by L. japonica and L. longissima. Dongfang No.2 held both ‘T’ and ‘C’ at position 847 of the ITS region, while ‘T’ at this position was specific for L. japonica and ‘C’ for L. longissima, respectively. Dongfang No.2 also held the microsatellite DNA alleles of two parents together at two microsatellite DNA marker loci. These observations clearly proved that Dongfang No.2 is a true hybrid of L. japonica and L. longissiuma. Unfortunately, the origin of the chloroplast of Dongfang No.2 was not determined based on the variation of RuBisCo spacer. More sequence variants of both ITS region and RuBisCo spacer were identified in Dongfang No.2 and most of them did not exist in either L. japonica or L. longissima. The unexpected variants may be due to the mutation of ga- metophyte clones occurring during their vegetative amplification.The cultivation of the first filial generation of monoploid gametophyte clones of different Laminaria species （hybrid Laminaria） is an effective way of utilizing heterozygous vigor （heterosis）. A female gametophyte clone of L. japonica and a male gametophyte clone of L. longissima were hybridized, generating Dongfang No.2 hybrid Laminaria. The parentage of this hybrid Laminaria was determined using AFLP of total DNA, SNP of the ITS region of ribosomal RNA transcription unit and microsatellite DNA variation at two loci. In addition to 167 AFLP bands shared by Dongfang No.2, L. japonica and L. longissima, Dongfang No.2 hybrid Laminaria shared another 70 and 55 bands with L. japonica and L. longissima, respectively, which were obviously more than 11 bands shared by L. japonica and L. longissima. Dongfang No.2 held both ＇T＇ and ＇C＇ at position 847 of the ITS region, while ＇T＇ at this position was specific for L. japonica and ＇C＇ for L. longissima, respectively. Dongfang No,2 also held the microsatellite DNA alleles of two parents together at two microsatellite DNA marker loci. These observations clearly proved that Dongfang No.2 is a true hybrid of L. japonica and L. longissiuma. Unfortunately, the origin of the chloroplast of Dongfang No.2 was not determined based on the variation of RuBisCo spacer. More sequence variants of both ITS region and RuBisCo spacer were identified in Dongfang No.2 and most of them did not exist in either L. japonica or L. longissima. The unexpected variants may be due to the mutation of gametophyte clones occurring during their vegetative amplification.

关 键 词：hybrid Laminaria gametophyte clone heterosis Laminaria japonica Laminaria longissima 

分 类 号：Q949.4[生物学—植物学]