Gonzalo Maria Jose, da Maia Luciano Carlos, Nájera Inmaculada, Baixauli Carlos, Giuliano Giovanni, Ferrante Paola, Granell Antonio, Asins Maria Jose, Monforte Antonio Jose
Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, 46010 Valencia, Spain.
Plant Genomics and Breeding Center, Faculdade de Agronomia Eliseu Maciel, Universidade Federal de Pelotas, Pelotas 96010-610, RS, Brazil.
Plants (Basel). 2022 Apr 14;11(8):1069. doi: 10.3390/plants11081069.
In the present work, we study the genetic control of reproductive traits under different heat stress conditions in two populations of inbred lines derived from crosses between two accessions and two tomato cultivars (E9×L5 and E6203×LA1589). The temperature increase affected the reproductive traits, especially at extremely high temperatures, where only a few lines were able to set fruits. Even though a relative modest number of QTLs was identified, two clusters of QTLs involved in the responses of reproductive traits to heat stress were detected in both populations on chromosomes 1 and 2. Interestingly, several epistatic interactions were detected in the E9×L5 population, which were classified into three classes based on the allelic interaction: dominant (one locus suppressed the allelic effects of a second locus), co-adaptive (the double-homozygous alleles from the same parent alleles showed a higher phenotypic value than the combination of homozygous alleles from alternative parents) and transgressive (the combination of double-homozygous alleles from different parents showed better performance than double-homozygous alleles from the same parents). These results reinforce the important role of non-additive genetic variance in the response to heat stress and the potential of the new allelic combinations that arise after wide crosses.
在本研究中，我们研究了两个自交系群体在不同热应激条件下生殖性状的遗传控制，这两个自交系群体来源于两个种质与两个番茄品种（E9×L5和E6203×LA1589）之间的杂交。温度升高影响了生殖性状，尤其是在极高温度下，只有少数品系能够坐果。尽管鉴定出的数量性状基因座（QTL）相对较少，但在1号和2号染色体上的两个群体中均检测到了两个与生殖性状对热应激反应相关的QTL簇。有趣的是，在E9×L5群体中检测到了几种上位性互作，根据等位基因互作将其分为三类：显性（一个位点抑制第二个位点的等位基因效应）、共适应（来自同一亲本等位基因的双纯合等位基因表现出比来自替代亲本的纯合等位基因组合更高的表型值）和超亲（来自不同亲本的双纯合等位基因组合表现出比来自同一亲本的双纯合等位基因更好的性能）。这些结果强化了非加性遗传方差在热应激反应中的重要作用以及远缘杂交后出现的新等位基因组合的潜力。
