马尾松种子千粒重配合力及杂种优势分析

研究马尾松种子千粒重的遗传差异及配合力与杂种优势,为马尾松遗传改良提供基础数据。以采自湖南省城步马尾松种子园中来自湖南、贵州、广西等3个省(区)种源的161个马尾松半同胞家系和60个马尾松全同胞家系种子为材料,测定其千粒重,通过测交设计对其种子千粒重配合力及杂种优势进行分析。结果表明:单亲家系间、双亲家系间种子的千粒重差异均达极显著,种源间差异不显著。3个测交设计组合的父本间、母本间千粒重GCA效应值以及杂交组合间千粒重SCA效应值的差异均达极显著。第Ⅰ设计2个父本中千粒重GCA效应表现较好的亲本是龙潭,4个母本中,以48亲本的千粒重GCA效应值最大,但以87×龙潭杂交组合的SCA效应最好;第Ⅱ设计中,4个父本中千粒重GCA效应表现最好的亲本是75,2个母本中,表现较好的亲本是48,但以83×庆远16组合的SCA效应最好;第Ⅲ设计中,4个父本中千粒重GCA效应表现最好的亲本是48,2个母本中,表现较好的亲本是庆远16,但以庆远16×87组合的SCA效应最好。不同杂交组合千粒重的杂种优势差异很大,35个杂交组合千粒重杂种优势的变幅为-38.00%~24.75%。具有杂种优势的组合共14个,其中杂种优势在15%以上的组合4个;呈现一定的杂种劣势的组合21个。第Ⅰ设计中SCA效应最好的87×龙潭组合和第Ⅲ设计中SCA效应最好的庆远16×87组合,分别在其相应的设计中杂种优势最强。以上结果说明:由2个GCA最高的亲本组配的杂交组合,其SCA效应不一定是最好的;只有少数杂交组合千粒重的杂种优势表现优良;SCA最高的杂交组合,其杂种优势最强。

Thousand seed weight combining ability and heterosis analysis of Pinus massoniana

The thousand seed weight combining ability and heterosis analysis of Pinus massoniana was studied to provide basic data.Taken 161 half-sib family and 60 full-sib family seeds of Pinus massoniana in Chengbu Pinus massoniana seed orchard from Hunan,Guizhou and Guangxi provenance as materials,the thousand seed weight was determined and the thousand seed weight combining ability and heterosis was analyzed by cross design.The results showed that,there were significant differences in the thousand seed weight between single parent family seeds and parental family seeds,but there was no difference between provenances.There were significant differences in thousand seed weight GCA value between male parents and female parents and in thousand seed weight SCA value between cross combinations.In the first design, the male parent Longtan had better performance in thousand seed weight GCA value,the female parent 48 had the maxi-mum GCA value and 87 ×Longtan cross combination had the best performance in SCA value.In the second design,the male parent 75 and the female parent 48 had the best performance in thousand seed weight GCA value,and 83 × Qingyuan 16 combination had the best performance in SCA value.In the third design,the male parent 48 and the female parent Qingyuan 16 had the best performance in thousand seed weight GCA value,and Qingyuan 16 ×87 combination had the best performance in SCA value.The heterosis difference of thousand seed weight of different cross combinations was very big,the variation of thousand seed weight heterosis of 35 cross combinations was -38.00%~24.75%.14 cross combinations had heterosis,including 4 cross combinations heterosis of more than 15%,and 21 cross combinations had hybrid weakness.In the first design,the 87 ×Longtan combination with the best SCA effect had the strongest heterosis. And in the third design,the Qingyuan 16 ×87 combination with the best SCA effect had the strongest heterosis.These re-sults indicated that,the SCA effect of the cross combination of the two highest GCA equipping parents were not necessari-ly the best.There were few hybrid combination had strong heterosis of the thousand seed weight.And the hybrid combina-tion of the highest SCA had the strongest heterosis.