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941.
Despite apparently inadequate N levels throughout the Inland Northwest of the United States, trees on some sites showed no increased growth 6 yr after N fertilization. Nor did higher N application rates consistently produce higher response. These facts indicated that other factors are limiting tree growth at these sites. Results suggest that K status is one important factor, influencing N fertilization response in the following general ways: (1) for stands with low pretreatment foliar K levels, the amount and duration of growth response are reduced, and higher N fertilizer rates produce less response; and (2) for all stands, growth response declines when foliar K decreases after N fertilization. 相似文献
942.
Dylan Gwynn-Jones Wei Huang Gary Easton Roy Goodacre John Scullion 《Pedobiologia》2003,47(5-6):784-787
943.
Takeoka GR Dao LT Tamura H Harden LA 《Journal of agricultural and food chemistry》2005,53(12):4932-4937
A major anthocyanin was isolated from the acidified methanolic extract of Beluga black lentils by XAD7 column chromatography and preparative high-performance liquid chromatography. By means of electrospray ionization mass spectrometry and one- and two-dimensional nuclear magnetic resonance spectroscopy, its structure was determined to be delphinidin 3-O-(2-O-beta-D-glucopyranosyl-alpha-l-arabinopyranoside). 相似文献
944.
Determination of Sulfate,Nitrate, and Chloride in Throughfall using Ion-Exchange Resins 总被引:1,自引:0,他引:1
Simkin Samuel M. Lewis David N. Weathers Kathleen C. Lovett Gary M. Schwarz Kirsten 《Water, air, and soil pollution》2004,153(1-4):343-354
Throughfall, the solution that falls from the forest canopy, is an important and commonly measured flux in forest ecosystem studies. Throughfall water and chemistry are highly variable spatially, requiring large numbers of collectors to quantify it. This and the fact that the solution can be chemically unstable make throughfall sampling very labor intensive, thus we have developed a method to reduce the field labor portion of this effort. Our throughfall collection method uses compact ion exchange resin columns that need only be collected every 1–2 months. The resin columns are subsequently extracted with 1.0 M potassium iodide (KI), releasing anions back into solution, with extraction efficiencies > 94% for sulfate, nitrate, and chloride. The extracts are analyzed by ion-chromatography (IC) to determine the total microequivalents of anions per unit area of collector surface collected over the period of resin column exposure. This ion exchange resin method was originally developed for a project in which we needed to deploy over 300 throughfall collectors to quantify throughfall variability across mountainous terrain with heterogeneous vegetation. 相似文献
945.
Seasonal,annual, and treatment-induced variation in available nitrogen pools and nitrogen-cycling processes in soils of two Douglas-fir stands 总被引:2,自引:0,他引:2
Summary Forest-floor and 0–10 cm depth mineral soil horizons in two stands of Douglas fir were sampled for available NH4
+-N and NO3
–-N, N-mineralization potentials, and nitrification potentials for 2 years. The plots in each stand were sampled for 1 year, treated with either ammonium sulfate, carbohydrate (sawdust-sucrose), irrigation, carbohydrate plus irrigation, or no treatment (control), and then sampled for 1 year following treatment. In general, the direction of change following the treatments was the same for both the forest-floor and the mineral soils. Fertilization increased the NH4
+-N and NO3
–-N pools, nitrification potential, and N-mineralization potential, while treatment with carbohydrate decreased all of these characteristics. Irrigation generally increased NH4
+-N pools, nitrification potential, and N-mineralization potential, but decreased these characteristics in the soil at one site. Irrigation plus carbohydrate gave similar results to those of carbohydrate alone. Treatments altered pool sizes and/or potentials, but did not reduce within-year variance in any of these characteristics. Distinct seasonal patterns occurred in all measurements, suggesting that control of short-term variation in N-transformation processes is by factors which are dynamic in nature. 相似文献
946.
K. Moore 《Euphytica》1966,15(3):329-347
- 1.The morphology and physiology of “grass-dwarfs” produced in the F1 generation of crosses between certain varieties of Triticum aestivum L. are described. Several treatments were successful in inducing these tufted grasslike plants to flower and set seed. This enabled the crosses producing grass-dwarfs in the F1 generation to be continued to the F2 generation where at least half the plants possess the normal wheat phenotype. 相似文献
947.
948.
Daryl L. Klindworth Gary A. Hareland Elias M. Elias Jae‐Bom Ohm Dehdra Puhr Steven S. Xu 《Cereal Chemistry》2014,91(3):211-217
Dual‐purpose durum (Triticum turgidum L. subsp. durum) wheat, having both good pasta and breadmaking quality, would be an advantage in the market. In this study, we evaluated the effects of genotype and varying HMW and LMW glutenin subunit composition on durum breadmaking quality. Genotypes included five near‐isogenic backgrounds that also differed by variability at the Glu‐D1d (HMW subunits 1Dx5+1Dy10), Glu‐B1 (presence or absence of subunit 1By8), and Glu‐B3 (LMWI or LMWII pattern) loci. Quality tests were conducted on genotypes grown at five North Dakota locations. Genotype had a stronger influence on free asparagine content than glutenin subunit composition. Genotypes carrying Glu‐D1d had higher glutenin content than lines that did not carry Glu‐D1d. Among Rugby translocation genotypes, lines carrying LMWI had higher gliadin content and better loaf volume than genotypes carrying LMWII. Absence of 1By8 produced major reductions in loaf volume in nontranslocation lines regardless of whether LMWI or LMWII was present. In contrast, the presence of Glu‐D1d compensated well for the absence of 1By8 regardless of which LMW pattern was present. The durum genotypes did not have loaf volumes equal to bread wheat cultivars, and results suggest that improved extensibility is needed to improve durum breadmaking quality. 相似文献
949.
950.