Department of Forest Botany, Institute of Forest Sciences, Warsaw University of Life Sciences - SGGW, 159 Nowoursynowska Street, 02-776, Warszawa, Poland.
Department of Botany and Plant Physiology, University of Life Sciences in Lublin, 15 Akademicka Street, 20-950, Lublin, Poland.
BMC Plant Biol. 2021 Mar 16;21(1):136. doi: 10.1186/s12870-021-02917-7.
Cleistogamic flowers are a main barrier in pollen dispersal for cross-pollination necessary in wheat hybrid breeding. The aim of our study was to gain new knowledge on the biology of wheat flowering, in particular on the differences between the cleisto- and chasmogamic forms which has certainly cognitive significance, but it can also be used in practice when seeking a female and male ideotypes for cross hybridization.
We characterized the most significant features defining the flowering specificity in two wheat cultivars with contrasting tendency to cleistogamy: Piko (chasmogamous) and Dacanto (cleistogamous). In the field observations we assessed diurnal pattern of anther extrusion and anther extrusion capacity. For the first time we adapted the time lapse method for measuring kinetics of the spikelet movement and 3-D image correlation technique for the non-invasive measurements of potential deformations of the spikelet lemmas. We found that the two cultivars differ in the potential of pollen dispersion for-cross-pollination and in the spikelet kinetics. We also described some anatomical traits that can have potential functional role in floret opening. None of the cultivars showed any symptoms of lemma surface deformation.
The cleistogamic and chasmogamic wheat cultivars differ significantly in the potential for pollen dispersion for cross-pollination, which is mainly related to anther extrusion capacity. Although none of these features differentiated the cultivars clearly, we assume, based on spikelet kinetics and the lack of lemmas surface deformation, that the water transport and turgor of cells is essential for the floret opening and anther extrusion in wheat. The search for parental ideotype should be supported by marker assisted selection, e.g. based of polymorphisms in genes related to aquaporin biosynthesis.
无融合生殖的花朵是花粉传播的主要障碍，对于小麦杂交育种中必需的异交来说是如此。我们研究的目的是获得有关小麦开花生物学的新知识，特别是关于无融合生殖和有性生殖形式之间的差异，这无疑具有认知意义，但在寻求杂交的雌性和雄性理想型时也可以在实践中使用。
我们描述了两个具有不同无融合生殖倾向的小麦品种的开花特异性的最显著特征：Piko（有性生殖）和 Dacanto（无融合生殖）。在田间观察中，我们评估了花药外伸的昼夜模式和花药外伸能力。我们首次适应延时方法测量小穗运动的动力学，以及 3D 图像相关技术进行小穗外稃的潜在变形的非侵入性测量。我们发现，两个品种在花粉散布潜力和小穗动力学方面存在差异。我们还描述了一些解剖特征，它们可能在小花张开中具有潜在的功能作用。两个品种均未表现出任何外稃表面变形的症状。
无融合生殖和有性生殖的小麦品种在异交花粉散布潜力方面存在显著差异，这主要与花药外伸能力有关。尽管这些特征没有一个能清楚地区分品种，但基于小穗动力学和外稃表面变形的缺乏，我们假设，水分运输和细胞膨压对于小麦小花张开和花药外伸是必不可少的。寻找亲本理想型应该得到标记辅助选择的支持，例如基于与水通道蛋白生物合成相关的基因多态性。
