Pisum fulvum is an annual legume native to Syria, Lebanon, Israel and Jordan. In certain locations, P. fulvum individuals were documented to display a reproductive dimorphism - amphicarpy, with both above and below ground flowers and pods. Herein we aimed to study the possible role of soil texture on amphicarpy in P. fulvum, to investigate the possible bio-climatic associations of P. fulvum amphicarpy and to identify genetic markers associated with this phenotype. A set of 127 germplasm accessions sampled across the Israeli distribution range of the species was phenotyped in two common garden nurseries. Land use and bioclimatic data were used to delineate the eco-geographic clustering of accession's sampling sites. Single nucleotide polymorphism (SNP) markers were employed in genome-wide association study to identify associated loci. Amphicarpy was subject to strong experimental site x genotype interaction with higher phenotypic expression in fine textured soil relative to sandy loam. Amphicarpy was more prevalent among accessions sampled in eastern Judea and Samaria and was weakly associated with early phenology and relatively modest above ground biomass production. Twelve SNP markers were significantly associated with amphicarpy, each explaining between 8 and 12 % of the phenotypic variation. In P. fulvum amphicarpy seems to be a polygenetic trait controlled by an array of genes that is likely to be affected by environmental stimuli. The probable selective advantage of the association between amphicarpy and early flowering is in line with its relative prevalence in drought prone territories subject to heavy grazing.

中文翻译：

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豌豆黄豆两性结实的环境和遗传决定因素，豌豆的野生近缘种

Pisum fulvum 是一种一年生豆科植物，原产于叙利亚、黎巴嫩、以色列和约旦。在某些地方，P. fulvum 个体被记录为表现出生殖二态性 - 两性，具有地上和地下的花朵和豆荚。在此，我们旨在研究土壤质地对 P. fulvum 两性结实的可能作用，研究 P. fulvum 两性结实的可能生物气候关联，并确定与该表型相关的遗传标记。在两个常见的花园苗圃中对以色列分布范围内采样的一组 127 个种质材料进行了表型分析。土地利用和生物气候数据被用来描绘种质采样点的生态地理集群。在全基因组关联研究中采用单核苷酸多态性 (SNP) 标记来识别相关位点。Amphicarpy 受到强烈的实验位点 x 基因型相互作用的影响，在细质地土壤中相对于砂壤土具有更高的表型表达。Amphicarpy 在东犹地亚和撒马利亚采样的种质中更为普遍，并且与早期物候和相对温和的地上生物量生产的相关性较弱。十二个 SNP 标记与两性显着相关，每个都解释了 8% 到 12% 的表型变异。在 P. fulvum amphicarpy 中，似乎是由一系列可能受环境刺激影响的基因控制的多遗传性状。两性结实和早花之间关联的可能选择优势与其在受重度放牧的干旱易发地区的相对普遍性一致。