Schmidt Constanze, Hinterberger Valentin, Philipp Norman, Reif Jochen C, Schnurbusch Thorsten
Leibniz Institute of Plant Genetics and Crop Plant Research, Corrensstr. 3, OT Gatersleben, D-06466 Seeland, Germany.
Martin Luther University Halle-Wittenberg, Faculty of Natural Sciences III, Institute of Agricultural and Nutritional Sciences, D-06120 Halle, Germany.
J Exp Bot. 2025 Jan 10;76(2):445-460. doi: 10.1093/jxb/erae430.
The performance of plant hybrids relative to line breeding types is generally associated with higher yields, better adaptation, and improved yield stability. In bread wheat (Triticum aestivum L.), however, a broad commercial success for hybrids has not been accomplished until now largely due to the low efficiency of hybrid grain production, which is highly attributable to its self-pollinating nature. To better understand how hybrid wheat grains can be produced more effectively, we investigated the influence of synchronized flowering between female (i.e. male-sterile) lines and their male cross-pollinator lines as well as of the duration of flowering on hybrid grain production. We found that synchronization of flowering in combination with the longest possible temporal overlap had the largest positive effect on hybrid grain production. However, despite sufficient spatial and temporal synchronization of flowering, we also found that some female lines had lower hybrid grain set than others, suggesting genetic differences in female floral receptivity. To better assess female receptivity, we established a new phenotyping scale of male-sterile wheat flowers that provides the floral basics for effective cross-pollination. Applying this scale in our field and greenhouse trials revealed that better performing female lines remained longer in the pollen-receptive phase.
与品系育种类型相比，植物杂交种的表现通常与更高的产量、更好的适应性以及更高的产量稳定性相关。然而，在面包小麦（普通小麦）中，杂交种至今尚未取得广泛的商业成功，这主要是由于杂交制种效率低下，而这很大程度上归因于其自花授粉的特性。为了更好地理解如何更有效地生产杂交小麦种子，我们研究了雌性（即雄性不育）系与其雄性异花授粉系之间花期同步以及开花持续时间对杂交种子生产的影响。我们发现，花期同步与尽可能长的时间重叠相结合，对杂交种子生产具有最大的积极影响。然而，尽管花期在空间和时间上有足够的同步性，我们还发现一些雌性系的杂交结实率低于其他雌性系，这表明雌性花的可授性存在遗传差异。为了更好地评估雌性可授性，我们建立了一种新的雄性不育小麦花表型分级标准，为有效的异花授粉提供了花的基础信息。在我们的田间和温室试验中应用该分级标准发现，表现较好的雌性系在花粉可授期停留的时间更长。
