Sharma Nirmal, Schneider-Canny Raquel, Chekhovskiy Konstantin, Kwon Soonil, Saha Malay C
Grass Genomics, Noble Research Institute, LLC, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA.
Powell Research and Extension Center, University of Wyoming, 747 Road 9, Powell, WY 82435, USA.
Plants (Basel). 2020 Dec 9;9(12):1738. doi: 10.3390/plants9121738.
Wheat is a major cool-season forage crop in the southern United States. The objective of this study is to understand the effect of nitrogen (N) fertilization on wheat biomass yield, quality, nitrogen use efficiency (NUE), and nitrogen nutrition index (NNI). The experiments were conducted in a greenhouse and a hoop house in a split-plot design, with three replications. Twenty wheat cultivars/lines were evaluated at four N rates (0, 75, 150, and 300 mg N.kg soil) in the greenhouse and (0, 50, 100, and 200 mg N.kg soil) in the hoop house. In general, high-NUE lines had lower crude protein content than the low-NUE lines. None of the cultivars/lines reached a plateau for biomass production or crude protein at the highest N rate. The line × N rate interaction for NUE was not significant in the greenhouse ( = 0.854) but was highly significant in the hoop house ( 0.001). NNI had a negative correlation with NUE and biomass. NUE had strong positive correlations with shoot biomass and total biomass but low to moderate correlations with root biomass. NUE also had a strong positive correlation with N uptake efficiency. Lines with high NUE can be used in breeding programs to enhance NUE in wheat for forage use.
小麦是美国南部一种主要的冷季饲料作物。本研究的目的是了解氮肥施用对小麦生物量产量、品质、氮素利用效率（NUE）和氮素营养指数（NNI）的影响。试验在温室和拱形棚内采用裂区设计进行，重复三次。在温室中以四种施氮量（0、75、150和300毫克氮·千克土壤）以及在拱形棚内以（0、50、100和200毫克氮·千克土壤）对20个小麦品种/品系进行了评估。一般来说，高氮素利用效率品系的粗蛋白含量低于低氮素利用效率品系。在最高施氮量下，没有一个品种/品系的生物量生产或粗蛋白达到平台期。氮素利用效率的品系×施氮量互作在温室中不显著（=0.854），但在拱形棚内极显著（0.001）。氮素营养指数与氮素利用效率和生物量呈负相关。氮素利用效率与地上部生物量和总生物量呈强正相关，但与根生物量呈低到中等程度的相关。氮素利用效率与氮素吸收效率也呈强正相关。高氮素利用效率的品系可用于育种计划，以提高用于饲料的小麦的氮素利用效率。
