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61.
62.
《Soil Use and Management》2018,34(1):72-84
Soya bean [Glycine max (L.) Merr] yields >6719 kg/ha (100 bu/ac) have only recently and infrequently been achieved. Quantifying soil property differences between high‐ and average‐yielding areas can help to further identify non‐plant‐related properties contributing to soya bean yield potential. The objective of this study was to evaluate the effects of region and soil depth on soil property differences between high‐ and average‐yielding areas. In each of the seven regions of the ‘Grow for the Green’ yield contest in Arkansas, prior to or just after harvest in 2014 and 2015, soil samples were collected from the top 20 cm of one contest high‐yield (HY ) area that was in close proximity to an average‐yield (AY ) area. Across all regions and both years, soya bean yields differed (P < 0.05) between yield areas, averaging 4701 and 5498 kg/ha in AY and HY areas, respectively. Averaged across soil depth and years, numerous soil properties differed (P < 0.05) between HY and AY areas within at least one of seven regions. Total soil C content was at least 20.2% greater in the HY than in the AY area in three of seven regions. Extractable soil P content was, on average, 19.4 kg/ha greater in HY than in AY areas in three of the seven regions. Results from this study have the potential to help producers better understand soil properties that contribute to or hinder achieving ultra‐high (>6719 kg/ha) soya bean yields. 相似文献
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64.
为促进优质食味粳稻品种在江苏淮北地区的推广应用,于2019年引进17个优质食味粳稻品种,以徐稻9号为对照,从生育期、抗逆性、丰产性、品质等方面进行综合评价。结果表明,供试的17个品种均能在安全齐穗期内齐穗(该地区安全齐穗期为9月15日前),生育期均处于安全期范围内。比对照增产的品种有7个,其中瑞华1903产量最高,达10888.5 kg/hm^2;圣稻022生育期最短,仅131 d;南粳518株高最矮,为95.7 cm。品质测定结果显示,武运粳1706整精米率和直连淀粉含量最高,分别达75.0%和16.2%;南粳5718、南粳518、南粳2728直链淀粉含量在10.0%左右,为优良食味粳稻品种。通过产量水平、农艺性状、生育期和品质等综合分析认为,供试品种中南粳518、南粳2728丰产性较好、株高较矮,且均为优良食味品种,生产中不仅产量潜力高、米质较优,同时早熟能有效规避低温危害和缓解淮北地区稻麦茬口季节紧张矛盾,适合淮北中熟中粳稻区人工栽插、机插和直播条件下大面积推广应用。 相似文献
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66.
通过设置黑豆-油菜、大豆-油菜的轮作模式在湖南醴陵进行大田试验,结果发现黑豆表现出较强的镉富集能力,其根、茎、叶及果壳中镉含量分别为2.14、2.63、4.10及1.34 mg/kg,富集系数均在1以上。油菜各个部位镉含量较高的分别为叶与茎,达到了7.13和4.73 mg/kg。黑豆各部位镉转运系数均高于大豆,各油料作物提取的重金属主要集中在茎与叶。大豆叶的镉富集系数为2.06,茎的镉富集系数为0.86,明显低于黑豆同部位的富集能力。每公顷土地经过一轮黑豆-油菜、大豆-油菜轮作分别能够从土壤中提取73.52 g和51.68 g的镉,对土壤重金属镉的修复效率约为3%。 相似文献
67.
Two wheat genetic lines (responsive and non-responsive to elevated CO2) grown under ambient and free-air CO2 enrichment (FACE) conditions were compared using fuzzy chromatography mass spectrometry (FCMS) metabolite fingerprinting. A more comprehensive survey of the changes in their chemical composition was made on selected samples using ultra-high-performance liquid chromatography (UHPLC) metabolomic profiling with high resolution accurate mass/tandem mass spectrometry (HRAM/MSn). Principal component analysis (PCA) of the metabolite fingerprints showed four clusters for the two genetic lines (responsive and non-responsive) and the two CO2 levels (ambient and elevated) in score plots. Metabolite profiling of representative samples for each of the four clusters identified 25 and 16 compounds from negative and positive data, respectively, including amino acids, saccharides, phenolic acids, flavonoids, and lipids. Loading plots demonstrated that some saccharides and lipids were responsible for discriminating between not only two genetic lines but also two CO2 levels. Analysis of free amino acids (not bound) showed a clear pattern of reduced concentration for both lines with elevated CO2. After acid hydrolysis, the responsive line 6 (41% increase in yield) showed the same pattern observed for free amino acids, but the non-responsive line 5 (6% increase in yield) showed different trends in concentrations of amino acids with elevated CO2. 相似文献
68.
Lien VANDE MAELE Marc HEYNDRICKX Dominiek MAES Nele DE PAUW Maxime MAHU Marc VERLINDEN Freddy HAESEBROUCK An MARTEL Frank PASMANS Filip BOYEN 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):325-328
The antibacterial potential of organic acids and essential oil components against Brachyspira
hyodysenteriae, the causative pathogen of swine dysentery, was evaluated. Minimum inhibitory
concentrations (MIC) of 15 compounds were determined at pH 7.2 and pH 6.0, using a broth microdilution assay.
In addition, possible synergism was determined. MIC values for the three tested strains were similar. For
organic acids, MIC values at pH 6.0 were lower than at pH 7.2. B. hyodysenteriae was most
sensitive to cinnamaldehyde and lauric acid, with MIC values <1.5 mM. Most antibacterial effects of binary
combinations were additive, however, for thymol and carvacrol, synergism could be observed. In
vitro results demonstrate the antibacterial action of certain essential oil components and organic
acids against B. hyodysenteriae. 相似文献
69.
The Newcastle disease inactivated vaccines were prepared with oil adjuvants respectively from domestic and import.The experiments were done in order to compare the new domestic oil and Marcol-52 according to a series of testing indexes. The results showed that the quality of the new domestic oil was better than Marcol-52, except the absorptive quality. 相似文献
70.