Alfalfa (Medicago sativa L.) semi‐hybrids of genetically distant material may display heterosis, but their agronomic value is hardly known. Our study evaluated two two‐way and one three‐way semi‐hybrids and two synthetic varieties for 3‐year herbage dry‐matter yield (DMY) in four agricultural environments of Northern Italy formed by the factorial combination of irrigated or rain‐fed cropping by pure stand (PS) or mixed stand (MS) with vigorous grasses to verify (1) the yield advantage of semi‐hybrid material and (2) the ability of a phenotyping platform with eight managed environments used in a prior study to reproduce the population adaptive responses in agricultural environments. The semi‐hybrids derived from putative heterotic populations selected from Italian germplasm, Egyptian germplasm, and a semi‐erect pool from Eastern Europe, Canada, and Spanish Mielga germplasm. The three‐way semi‐hybrid showed wide adaptation and over 17% greater DMY than a variety selected from the Italian genetic base (set as a reference for synthetic variety breeding). The two‐way semi‐hybrids showed specific adaptation to the irrigated MS environment (where alfalfa was outcompeted) or PS environments that agreed with features of their exotic parent population, and over 19% greater yield than the reference synthetic variety in the environments where they were specifically adapted. The phenotyping platform reproduced largely the population × environment interaction effects across agricultural environments.

中文翻译：

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紫花苜蓿半杂交种在意大利对比环境中的农艺价值


遗传相距遥远的材料的紫花苜蓿 （Medicago sativa L.） 半杂交种可能表现出优势，但它们的农艺价值几乎不为人知。我们的研究评估了意大利北部四个农业环境中两个双向和一个三向半杂交品种和两个合成品种的 3 年草料干物质产量 （DMY），这些品种由纯林 （PS） 或混合林分 （MS） 与旺盛的草形成的灌溉或雨养作物的因子组合形成，以验证 （1） 半杂交材料的产量优势和 （2） 具有八个托管环境的表型平台的能力在先前的研究中用于重现农业环境中的种群适应性反应。半杂交种来源于从意大利种质、埃及种质和来自东欧、加拿大和西班牙 Mielga 种质的半直立库中选择的推定种群。三向半杂交种显示出广泛的适应性，并且比从意大利遗传基础中选择的品种（作为合成品种育种的参考）高出 17% 以上。双向半杂交种显示出对灌溉 MS 环境（苜蓿被击败）或 PS 环境的特异性适应，这与它们的外来亲本种群的特征一致，并且在它们被专门适应的环境中，产量比参考合成品种高 19% 以上。表型平台在很大程度上再现了农业环境中种群×环境相互作用的影响。