Górny Andrzej G, Garczyński Sebastian
Institute of Plant Genetics, Polish Academy of Sciences, Poznań, Poland.
J Appl Genet. 2002;43(2):145-60.
Effects of high and reduced NPK nutrition on the genetic variation of components of water use efficiency at the leaf and whole-plant levels were examined in pot-grown old and modern cultivars of winter wheat (Triticum aestivum L.). At the subsequent growth stages, the photosynthetic rate (A), transpiration rate (E), leaf area (LA) and gas exchange efficiency (A/E) were measured on fully developed 4th, 5th, penultimate and flag leaves. At the plant canopy level, the total amount of water transpired was recorded during the whole life cycle to determine the efficiency of water use in the vegetative (WUEveg) and grain (WUEgen) matter formation. Considerable genotypic differences were found for the characters studied. The limited NPK supply caused a decrease in LA, A and A/E, but contributed to an increase in WUEgen. Examined cultivars (C) did not interact with nutrition levels (N) for these characteristics. However, the position of leaves (L) and the C x L and N x L interactions significantly affected the variance in leaf photosynthetic characteristics. A and A/E were negatively correlated with LA, and the flag leaves were photosynthetically less active and less efficient per unit area than the lower leaves. The whole-plant components of WUE were found to be more genetically stable than the photosynthetic leaf characteristics. Some modern cultivars tended to form leaves of higher A and A/E than the older ones, and this corresponds with a more efficient use of water in grain formation (WUEgen) of the former. Stay-green duration of flag leaves and harvest index showed positive correlations with WUEgen. However, no close associations were noticed between WUE components and stress tolerance, and the modern cultivars were usually less tolerant to NPK shortage.
在盆栽的冬小麦（Triticum aestivum L.）老品种和现代品种中，研究了高氮磷钾营养和低氮磷钾营养对叶片和整株水平水分利用效率组成部分遗传变异的影响。在随后的生长阶段，对完全展开的第4片、第5片、倒数第二片和旗叶测量光合速率（A）、蒸腾速率（E）、叶面积（LA）和气体交换效率（A/E）。在植株冠层水平，记录整个生命周期内的总蒸腾水量，以确定营养物质形成（营养器官水分利用效率，WUEveg）和籽粒形成（籽粒水分利用效率，WUEgen）过程中的水分利用效率。在所研究的性状上发现了显著的基因型差异。有限的氮磷钾供应导致叶面积、光合速率和气体交换效率降低，但有助于籽粒水分利用效率的提高。对于这些性状，所研究的品种（C）与营养水平（N）之间没有相互作用。然而，叶片位置（L）以及品种与叶片位置的互作（C×L）和营养水平与叶片位置的互作（N×L）显著影响叶片光合特性的变异。光合速率和气体交换效率与叶面积呈负相关，旗叶的光合活性和单位面积效率低于下部叶片。发现整株水平的水分利用效率组成部分比光合叶片特性在遗传上更稳定。一些现代品种往往比老品种形成具有更高光合速率和气体交换效率的叶片，这与前者在籽粒形成过程中更高效的水分利用（籽粒水分利用效率）相对应。旗叶的持绿期和收获指数与籽粒水分利用效率呈正相关。然而，未发现水分利用效率组成部分与胁迫耐受性之间有密切关联，并且现代品种通常对氮磷钾短缺的耐受性较低。
