4x-4x和4x-2x杂种后代高世代选系比重的比较

Comparison for Specific Gravity of Advanced Clones Selected from 4x-4x and 4x-2x Crosses

马铃薯的比重是加工企业要考虑的一个重要性状。本研究的目的是比较4x-4x和4x-2x杂种后代高世代选系的比重,试图利用单向有性多倍化(Unilateral sexual polyploidization,USP)的方法从二倍体栽培种向四倍体普通栽培种转育高比重基因。四倍体亲本为品种或高世代选系,二倍体亲本是普通马铃薯栽培种(Solanum tuberosum)双单倍体与二倍体栽培种富利亚(S.phureja)杂种的互交后代,或经轮回选择适应长日照的S.phureja-S.stenotomum杂种后代。从4x-4x和4x-2x组合各选出17个高世代无性系,以‘克新18号’(鲜食)和‘夏坡地’(薯条加工)为对照,采用随机区组设计,2011～2012年在黑龙江省的加格达奇评价了4x-4x和4x-2x高世代选系比重的表现。4x-2x和4x-4x后代高世代选系比重平均为1.0727和1.0659,二者差异极显著。但是,4x-2x内和4x-4x内无性系的差异仍达极显著水平。4x-2x四倍体后代HJ04-18-17,HJ04-27-41,HJ04-22-19以及HJ04-15-36比重高于对照品种‘夏坡地’,并和其有显著差异。结果表明,和4x-4x组合相比,4x-2x组合后代含有较高的比重。

Specific gravity is an important character to be considered in potato processing. The purposes of this research were to compare the specific gravity of advanced clones selected from 4x-4x and 4x-2x cresses and try transferring high specific gravity genes from cultivated diploid species to tetraploid cultivars. Tetraploid parents were cultivars or advanced selections; diploid parents were intercrossing progenies of haploid Tuberosum-Phureja hybrids, or S. phureja-S, stenotomum hybrids undergone current selection for long-day adaptation. Seventeen advanced clones were selected out from each type of 4x-4x and 4x-2x crosses and evaluated for their specific gravity in a randomized complete block design at Jiagedaqi, Heilongjiang in 2011 and 2012, using ＇Kexin 18＇ （table potato） and ＇Shepody＇ （French fry） as controls. The average of specific gravity of advanced clones from 4x-2x and 4x-4x crosses were 1.0727 and 1.0659, respectively, the difference being significant. However, variations within 4x-2x and 4x-4x crosses were still highly significant. HJ04-18-17, HJ04-27-41, HJ04-22-19 and HJ04-15-36, all from 4x-2x crosses, were significantly higher in specific gravity than the control culUvar ＇Shepody＇. The results indicated that advanced clones selected from 4x-2x crosses had higher specific gravity than those from 4x-4x crosses.