Yu Daoliang, Zhang Shengping, Miao Han, Dong Shaoyun, Liu Xiaoping, Shi Lixue, Xie Qing, Wang Weiping, Wei Shuang, Gu Xingfang, Bo Kailiang
State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081 China.
Mol Breed. 2025 Mar 4;45(3):30. doi: 10.1007/s11032-025-01551-7. eCollection 2025 Mar.
Heterosis has been widely applied in crops production. Nonetheless, how to determine the favorable recombination of non-alleles remains elusive. Due to the uncertainty of genetic recombination, hybrids with strong heterosis tend to be selected empirically, by developing and testing a tremendous number of combinations. Here, we found some individuals in recombinant inbred lines (RILs, F) that were generated from hybrid F (HRF) with heterosis performed transgressive segregation for yield in multiple environments. The result suggested that the formation of yield heterosis in hybrid was caused by the effective recombination of genes or QTLs. We performed multiple regression analysis (MRA) and redundancy analysis (RDA) using 11 traits measured in four environments. Of these traits, percentage of female flowers (PFF), fruit length (FL), fruit neck length (FNL), vine length (VL) and vine diameter (VD) contributed to increase yield. Moreover, the genes or QTL of yield contributor traits were identified by the molecular mapping strategy. We predicted a candidate gene that encoding a KIP1-like protein through correlation analysis between haplotype and fruit length phenotype. Based on the phenomenon some RILs individuals performed transgressive segregation and genetic theory, we proposed the model that the genetic sources of heterosis are contributed by combination of heterozygotic advantages and genetic recombination effects. Our work provides the theoretical basis for the pyramid of contributor genes or QTL for yield heterosis. This work also may facilitate Marker-assisted Selection for promote hybrid pyramid breeding and makes yield increasing more predictable in cucumber.
The online version contains supplementary material available at 10.1007/s11032-025-01551-7.
杂种优势已在作物生产中广泛应用。然而，如何确定非等位基因的有利重组仍不清楚。由于基因重组的不确定性，具有强大杂种优势的杂交种往往是通过开发和测试大量组合来凭经验选择的。在这里，我们发现从具有杂种优势的杂交种F（HRF）产生的重组自交系（RILs，F）中的一些个体在多个环境中产量表现出超亲分离。结果表明，杂交种中产量杂种优势的形成是由基因或QTL的有效重组引起的。我们使用在四个环境中测量的11个性状进行了多元回归分析（MRA）和冗余分析（RDA）。在这些性状中，雌花百分比（PFF）、果实长度（FL）、果颈长度（FNL）、藤蔓长度（VL）和藤蔓直径（VD）有助于提高产量。此外，通过分子定位策略鉴定了产量贡献性状的基因或QTL。通过单倍型与果实长度表型之间的相关性分析，我们预测了一个编码KIP1样蛋白的候选基因。基于一些RILs个体表现出超亲分离的现象和遗传理论，我们提出了杂种优势的遗传来源是由杂合优势和基因重组效应共同作用的模型。我们的工作为产量杂种优势贡献基因或QTL的聚合提供了理论基础。这项工作也可能有助于标记辅助选择以促进杂交种聚合育种，并使黄瓜产量增加更具可预测性。
在线版本包含可在10.1007/s11032-025-01551-7获取的补充材料。
