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1.
《Communications in Soil Science and Plant Analysis》2012,43(5):451-458
Abstract This study reports on a procedure where ryegrass (Lolium multiflorum Lam.) varieties are screened for tolerance to aluminum toxicity. The procedure utilized was a solution‐paper method where seedlings were grown on filter paper which transported nutrient solution from a reservoir. Mean root length for genotypes was the character utilized to determine tolerance to aluminum toxicity. Ryegrass genotypes were subjected to [Al] between 0 to 8 mM with the most useful concenrations being from 2 to 4 mM. Genotypes which demonstrated some tolerance to higher [Al] were North American Plant Breeders R. 0051, ‘Aubade’, ‘Urbana’, Fla 1977B, ‘Tetragulf, Mommersteeg Lmw 96. Considerable variation in root length due to genotypic effect tended to obscure the [Al] effect. The relative rankings of root growth ratios of 4 mM [Al] to 2 mM [Al] tolerance of ryegrass cultivars is questionable. Further work to establish a more reliable screening technique for this specie needs to be undertaken. 相似文献
2.
Abstract. Results are presented from three years (1992-1995) of a field leaching experiment on a sandy soil in south-west Sweden. Plots of spring cereals, either with or without an undersown perennial ryegrass catch crop, were compared for nitrogen leaching and nitrogen status in soil. Both treatments were ploughed in spring, and other tillage regimes were also identical. Measurements of nitrogen leaching from drains, nitrogen uptake in crops and mineral nitrogen in the soil were made. Two coupled, simulation models, which describe water flow and nitrogen transformations and transport in soil, were used to interpret data and to calculate the nitrogen budget and nitrogen mineralization in the soil.
Nitrogen leaching was 40 50% less in the catch crop treatment compared with the control during years when the establishment of the catch crop succeeded. In the third year of the experiment nitrogen leaching was actually greater in the catch crop treatment (7 kg N/ha). This increase was caused by a poorly established catch crop coinciding with enhanced mineralization of previous catch crop residues. There was no simulated change in soil organic nitrogen in either of the treatments. Simulations showed increased nitrogen mineralization during April-July after incorporation of plant material in spring, especially in the catch crop treatment. However, the increased nitrogen mineralization probably occurred too late for the released nitrogen to be fully available to the main crop. 相似文献
Nitrogen leaching was 40 50% less in the catch crop treatment compared with the control during years when the establishment of the catch crop succeeded. In the third year of the experiment nitrogen leaching was actually greater in the catch crop treatment (7 kg N/ha). This increase was caused by a poorly established catch crop coinciding with enhanced mineralization of previous catch crop residues. There was no simulated change in soil organic nitrogen in either of the treatments. Simulations showed increased nitrogen mineralization during April-July after incorporation of plant material in spring, especially in the catch crop treatment. However, the increased nitrogen mineralization probably occurred too late for the released nitrogen to be fully available to the main crop. 相似文献
3.
Peter Sørensen Betina N. Pedersen Ingrid K. Thomsen Jørgen Eriksen Bent T. Christensen 《植物养料与土壤学杂志》2023,186(4):441-450
Background
A high use-efficiency of fertilizer N remains essential to sustain high crop productivity with low environmental impact. However, little is known on the long-term lability of mineral fertilizer N.Aims
To quantify crop uptake and leaching of 15N-labelled mineral fertilizer that has been retained in an agricultural soil for 25–30 years in crops with variable growing season.Methods
A field plot received 15N-labelled mineral fertilizers over a period of 5 years and was then kept under arable cropping for 12 years. After relocation to 16 lysimeters, the topsoil grew set-aside grassland for the next 13 years. Then crop uptakes and leaching losses of 15N remaining in soil was tested over a 2-year period by either converting set-aside grass to production grassland, or by replacing it with spring barley (+/− autumn cover crop) or vegetation-free fallow. All treatments received unlabelled mineral N fertilizers.Results
Crop uptake and leaching of 15N were generally highest in the first test year after termination of the set-aside. The leaching of residual 15N in soil declined in the order: vegetation-free soil (4.7%), spring barley (1.9%), spring barley + cover crop (0.7%) and production grassland (0.2%). Corresponding losses for the second leaching period were 2.7%, 0.9%, 0.4% and 0.06%. There was a fixed relationship between leaching losses of 15N and total N.Conclusions
After residing in soil for 25–30 years, the lability of labelled mineral N fertilizer residues appeared slightly higher than the lability of bulk soil N. Autumn vegetation was crucial for reducing leaching losses. 相似文献4.
铝胁迫对黑麦草根系抗氧化酶活性和丙二醛含量的诱导特征研究 总被引：1，自引：0，他引：1
以多花黑麦草(Lolium multiflorum)为试材,通过水培试验方法,研究不同浓度梯度铝胁迫对黑麦草幼苗根系抗氧化酶活性和丙二醛含量的诱导特征,从而揭示黑麦草根系耐铝机制。结果表明:(1)在整个试验过程中,SOD、POD、CAT活性变化规律相一致。当铝浓度介于0~50 mg L-1范围内,SOD、POD、CAT在整个实验过程中活性显著增加(P<0.05),高于对照,并在50 mg L-1铝浓度处理下,活性达到最大;当铝浓度为100 mg L-1时,SOD、POD、CAT在铝处理时间≤8 h时活性显著增加(P<0.05),高于对照,在铝处理时间>8 h时活性明显降低(P<0.05),低于对照;当铝浓度介于100~500 mg L-1范围内,SOD、POD、CAT在整个实验过程中活性先升高(≤8 h)后降低(>8 h),均明显低于对照(P<0.05)。(2)MDA含量变化趋势同SOD、POD、CAT活性变化趋势正好相反。当铝浓度介于0~50 mg L-1范围内,MDA在整个实验过程中含量显著降低(P<0.05),低于对照,并在50 mg L-1铝浓度处理下,含量达到最小;当铝浓度为100 mg L-1时,MDA在铝处理时间≤8 h时含量显著降低(P<0.05),低于对照,在铝处理时间>8 h时含量明显升高(P<0.05),高于对照;当铝浓度介于100~500 mgL-1范围内,MDA在整个实验过程中含量先降低(≤8 h)后升高(>8 h),均明显高于对照(P<0.05)。研究结果表明黑麦草根系在短时间内对铝胁迫有一定的耐性,并且耐受范围随着铝处理时间的延长而变小。 相似文献
5.
J. Petersen I. K. Thomsen L. Mattsson E. M. Hansen B. T. Christensen 《Soil Use and Management》2010,26(4):455-464
Organic inputs [e.g. animal manure (AM) and plant residues] contribute directly to the soil organic N pool, whereas mineral N fertilizer contributes indirectly by increasing the return of the crop residues and by microbial immobilization. To evaluate the residual effect of N treatments established in four long‐term (>35 yr) field experiments, we measured the response of barley (grain yield and N offtake at crop maturity) to six rates (0, 30, 60, 90, 120 and 150 kg N/ha) of mineral fertilizer N (Nnew) applied in subplots replacing the customary long‐term plot treatments of fertilizer inputs (Nprev). Rates of Nprev above 50–100 kg N/ha had no consistent effect on the soil N content, but this was up to 20% greater than that in unfertilized treatments. Long‐term unfertilized plots should not be used as control to test the residual value of N in modern agriculture with large production potentials. Although the effect of mineral Nprev on grain yield and N offtake could be substituted by Nnew within a range of previous inputs, the value of Nprev was not eliminated irrespective of Nnew rate. Provided a sufficient supply of plant nutrients other than N, the use‐efficiency of Nnew did not change significantly with previous mineral N fertilizer rate. The residual effect of mineral N fertilizer was negligible compared with the residual effect of N from AM and catch crop residues. 相似文献
6.
7.
The cation exchange capacity of roots (CECR) has been measured according to three different methods : titration of H‐roots with NaOH in the presence of CaCl2, MgCl2, or NaCl 0.1 N, saturation of roots with mixed Ca‐Mg‐Na solutions of eight different compositions and extraction of the adsorbed cations with copper, saturation of roots with Cu‐ions and extraction with HC1. Two types of roots were studied : roots of ryegrass (Lolium multiflorum Lm.) and roots of clover (Trifolium pratense L.)
The very good coincidence of the results from the three methods tends to prove the reliability of the experimental procedures. The simplicity and the reproducibility of the Cu‐method renders it recommendable in view of possible standardization of the methods in the future. 相似文献
8.
铝胁迫对黑麦草种子萌发和幼苗生长的影响 总被引：4，自引：0，他引：4
以多花黑麦草为试材,通过水培试验,研究铝浓度对黑麦草种子萌发及其幼苗生长的影响。结果表明：（1）10～50 mg/L铝浓度对黑麦草种子发芽指数和发芽率无显著影响（p〉0.05）,而铝浓度介于100～500 mg/L时,与对照相比,黑麦草种子发芽指数和发芽率显著降低（p〈0.05）;（2）铝浓度介于10～500 mg/L时,显著抑制黑麦草幼苗株高及其根的生长（p〈0.05）,且随着铝浓度的增加抑制作用越强,当铝浓度介于100～500 mg/L时,黑麦草根系停止生长;（3）铝浓度显著影响了黑麦草的质膜透性,与对照相比,10 mg/L铝浓度显著降低了其质膜透性（p〈0.05）;而50～500 mg/L铝浓度则使黑麦草质膜透性显著增加（p〈0.05）。 相似文献
9.
Ruzica Stricevic Aleksandar Simic Alpaslan Kusvuran Marija Cosic 《Archives of Agronomy and Soil Science》2017,63(9):1301-1313
Given that the optimal sowing rate and inter-row spacing of Italian ryegrass raised for seed have not been determined, the objective of this research was to assess the effect of crop density on biomass and seed yields under different climate conditions, applying the AquaCrop model. The data came from experiments conducted under moderate continental climate conditions at Stitar (Serbia) and Mediterranean climate conditions at Cukurova (Turkey). At Stitar, there were three different inter-row spacings (high (Sd), medium (Sm) and low (Sw) crop densities), while at Cukurova there was only high crop density (Sn). In the calibration process, the initial canopy cover, canopy expansion and maximal canopy cover were adapted to each crop density, while the other conservative parameters were adjusted to correspond to all climate conditions. Calibration results showed a very good match between measured and simulated seed yields; the values of the coefficient of determination (0.922). The biomass simulation was very good for Cukurova (R2 = 0.97), but somewhat poorer for Stitar (R2 = 0.72). Other statistical indicators were high such as Willmott index of agreement of both the calibrated and validated data sets, for both study areas >0.916 and normalized root mean square error in the range from 9–18%. The AquaCrop model was found to be more reliable for Italian ryegrass biomass and seed yield predictions under mild winter climate conditions, with adequate water supply, compared with moderate climate and water shortage conditions. 相似文献
10.
Changes of EUF‐extractable nitrogen (N) (nitrate, ammonium, organic N) in 20 arable bare soils, subsequently planted with ryegrass (Lolium multiflorum L.) and cutting three times were investigated in pot experiments. All 20 soils responded qualitatively in the same way. During the period of bare soil, there was a significant increase of EUF‐extractable nitrate (EUF NO ), while extractable ammonium (EUF NH ) remained on the same level and organic N (EUF Norg) decreased. This decrease, however, was not significant. From sowing until the first cutting of the grass, EUF‐NO concentration decreased to almost zero. This low EUF‐NO level was maintained throughout the subsequent experimental period (three cuttings of grass). During the growth of the first cutting, EUF Norg decreased while EUF NH remained constant, however, on a low level. EUF NH fell during the growth of the second and third cutting. In this period, however, the N supply of the grass was insufficient. EUF Norg decreased during the growth of the second cutting, but increased during the growth of the third cutting. This shows that the EUF‐Norg fraction represents a transient pool, which gains and loses N. EUF NO , EUF NH , and EUF Norg correlated with the N uptake of the grass. Strongest correlation for EUF NO was found for the first cutting (p < 0.001), and for EUF NH and EUF Norg for the second and third cutting (p < 0.001). Total soil N was not correlated with the N uptake of the grass. EUF Norg was only about 2% of the total N. This relatively small EUF‐Norg fraction, however, is relevant for the mineralization of organic soil N, and the N quantity indicated by EUF Norg is in the range of the N amount mineralized in arable soils within a growing season. 相似文献
11.
污泥有机肥改良铅锌尾矿对4种草本植物生长和重金属积累的影响 总被引：1，自引：0，他引：1
[目的]研究添加不同量的污泥有机肥对生长在铅锌尾矿中的黑麦草、白三叶、草木樨、沙打旺4种植物生长状况和对Pb,Zn,Cu,Cr,Cd累积的影响,以期为合理利用污泥有机肥改良、修复尾矿库提供理论依据。[方法]采用盆栽试验的方法。[结果]20g/kg处理水平下,4种植物株高、根长、地上鲜重、根鲜重均达到最大。施肥处理下,供试的4种植物叶绿素a+b含量均比对照高。随着改良剂含量的增加,黑麦草、白三叶丙二醛含量呈下降趋势。黑麦草、白三叶、草木樨体内Pb,Zn,Cd含量在10g/kg处理水平下达到最大,在20g/kg水平下降低。[结论]随着有机肥添加量的增加,重金属量向植物体内转移减少,有利于缓解重金属的毒害作用。 相似文献
12.
《Communications in Soil Science and Plant Analysis》2012,43(2):153-162
Nitrogen (N) loss by ammonia (NH3) volatilization is the main factor for poor efficiency of urea fertilizer applied to the soil surface. Losses can be suppressed by addition of zeolite minerals to urea fertilizer. The objective of this study was to evaluate ammonia volatilization from soil and dry-matter yield and nitrogen levels of Italian ryegrass. A greenhouse experiment was carried out with the treatments of urea, urea incorporated into soil, urea + urease inhibitor, urea + zeolite, ammonium nitrate, and unfertilized treatment. Ammonia was captured by a foam absorber with a polytetrafluoroethylene tape. There were few differences between zeolite and urease inhibitor amendments concerning NH3 volatilization from urea. Results indicate that zeolite minerals have the potential to improve the N-use efficiency and contributed to increasing N uptake. Zeolite and urea mixture reduced 50% the losses by volatilization observed with urea. 相似文献
13.
E.-A. Kaiser K. Kohrs M. Kücke E. Schnug J. C. Munch O. Heinemeyer 《Biology and Fertility of Soils》1998,28(1):36-43
N2O emission rates from a sandy loam soil were measured in a field experiment with 2 years of perennial forage crops (ryegrass, ryegrass-red clover, red clover) and 1 year of spring barley cultivation. Spring barley was sown after the incorporation of the forage crop residues. All spring barley plots received 40 kg N ha–1 N fertiliser. Ryegrass, ryegrass-red clover and red clover plots were fertilised with 350 kg N ha–1, 175 kg N ha–1 and 0 kg N ha–1, respectively. From June 1994 to February 1997, N2O fluxes were continuously estimated using very large, closed soil cover boxes (5.76 m2). In order to compare the growing crops, the 33 months of investigation were separated into three vegetation periods (March–September) and three winter periods (October–February). All agronomic treatments (fertilisation, harvest and tillage) were carried out during the vegetation period. Large temporal changes were found in the N2O emission rates. The data were approximately log-normally distributed. Forty-seven percent of the annual N2O losses were observed to occur during winter, and mainly resulted from N2O production during daily thawing and freezing cycles. No relationship was found between the N2O emissions during the winter and the vegetation period. During the vegetation period, N2O losses and yields were significantly different between the three forage crops. The unfertilised clover plot produced the highest yields and the lowest N2O losses on this soil compared to the highly fertilised ryegrass plot. Total N2O losses from soil under spring barley were higher than those from soil under the forage crops; this was mainly a consequence of N2O emissions after the incorporation of the forage crop residues. Received: 31 October 1997 相似文献
14.
The effects of various measures introduced to increase nitrogen (N)‐use efficiency and reduce N losses to water in a 6‐yr crop rotation (winter wheat, spring barley, green manure, winter wheat, spring barley, spring oilseed rape) were examined with respect to N leaching, soil mineral N (SMN) accumulation and grain yield. An N‐use efficient system (NUE) with delayed tillage until late autumn and spring, direct drilling of winter wheat, earlier sowing of winter and spring crops and use of a catch crop in winter wheat was compared with a conventional system (CON) in a field experiment with six separately tile‐drained plots in south‐western Sweden during the period 1999–2011 (two crop rotation cycles). Total leaching of NO3‐N from the NUE system was significantly 46 and 33% lower than in the CON system during the first and second crop rotation cycle, respectively, with the most pronounced differences apparently related to management strategies for winter wheat. Differences in NO3‐N leaching largely reflected differences in SMN during autumn and winter. There was a tendency for lower yields in the NUE system, probably due to problems with couch grass. Overall, the measures for conserving N, when frequently used within a crop rotation, effectively reduced NO3 concentrations in drainage water and NO3‐N leaching losses, without severely affecting yield. 相似文献
15.
多花黑麦草杂交种SSR分子标记鉴定及表型比较分析 总被引：2，自引：0，他引：2
多花黑麦草为异花受粉植物,杂交过程中易出现杂交种生物性混杂现象,有必要对杂交后代进行真假鉴定分析.本研究旨在筛选出多花黑麦草优势杂交组合和优异杂交后代材料,为多花黑麦草杂交育种工作提供基础资料.实验利用SSR分子标记辅助鉴定5个多花黑麦草(Lolium multiflorum)骨干品种为亲本创制的杂种后代真实性,并对亲本与杂种后代主要表型进行比较.结果表明:(1)用20对引物组合共得到多态性条带426条,多态性位点百分率为82.41％,说明SSR分子标记能够很好的揭示多花黑麦草材料间的差异;(2)经SSR分子鉴定,将后代分为有父本特征谱带的杂种后代、无父本特征带的后代2类,在150个杂交后代单株中有父本特征谱带的杂种后代有108个为真杂种,其中杂交组合GC、CG真杂种最多均为24个,WG组合真杂种最少为19个;(3)杂交组合CG的F1代部分形态特征显著优于亲本,5个杂交组合内(间)在营养器官与生殖器官性状均存在显著差异,其中杂交组合MG的变异系数最高,WG的变异系数最低,杂交组合CG形态特征显著高于其他杂交组合.由研究结果可以初步判断长江2号×赣选一号多花黑麦草为优势杂交组合,其杂交种为优异杂交后代材料,可为后续杂交选育新品系提供后备材料. 相似文献
16.
Jose´ Alberto Oliveira Ruth Lindner Rezar Bregu Alvaro García Antonio Gonza´lez 《Genetic Resources and Crop Evolution》1997,44(5):479-487
Sixteen landraces of westerwold ryegrass (Lolium multiflorum Lam. var. westerwoldicum Wittm.) collected in Northwest Spain were evaluated at three locations: Mabegondo (La Corun~a), Puebla de Brollo´n (Lugo) and Salcedo (Pontevedra). Populations showed a high variability for morphologic, agronomic and isoenzimatic traits. Principal component analysis was carried out to identify clusters of morphologic and agronomic homogeneous behaviour. A hierarchical clustering method on the first five components was used to separate the different groups. A partition into four clusters was chosen (71% of variance explained). Each cluster was described by the means of the different traits and compared with the other clusters. Landraces were screened for allozyme diversity at nine loci. Population genetic statistics were higher than those previously reported for other outbreeding species (mean number of alleles = 3.59 and mean expected heterozygosity = 0.510). Genetic diversity was mainly explained by the within population component. The between population differentiation only accounted for 8% of the whole diversity. The use of these genetic resources is discussed. 相似文献
17.
Catch crops might reduce sulfate leaching and thereby increase the overall sulfur (S)‐use efficiency in crop rotations. At two experimental sites in Denmark (a sandy loam and a coarse sand), S uptake of catch‐crop species was measured. Furthermore, net release of S following incorporation of this material (S contents 0.13%–1.03%, C:S ratios of 40–329, and lignin contents of 1%–10.8%) was investigated in a pot experiment with spring barley in sandy soil. The catch crops showed huge differences in their ability to sequester S. The best catch crops (legumes on sandy loam), sequestered 10–12 kg S ha–1, and the poorest catch crops (ryegrass and sorrel on coarse sand) sequestered less than 3 kg S ha–1. The S‐mineralization rates were highest for crucifers (57%–85% of total S added) and lowest for legumes (up to 46% of total S added). Differences can partly be explained by the C:S ratio, whereas no significant relationship was found with the lignin content of the incorporated catch crops. Catch crops may help to avoid S deficiency and increase synchrony between plant demand and available soil S in a crop rotation. However, the release of S will not fulfil the need of S‐demanding crops and even for cereals, the mineralization will most often only make a contribution. In the case of legume catch crops, it is advisable to use a supplemental S source. 相似文献
18.
在四川省丹棱县退耕还林地上,采用网袋法对两种草本层(黑麦草和自然草)台湾桤木林地中细根分解及养分释放的对比,以及对台湾桤木 黑麦草复合模式草根与细根混合分解进行了为期1 a的实验研究。结果表明:台湾桤木细根在复合模式和自然模式中分解速率、养分释放有所不同,经过1 a的分解,复合模式中N,K,Ca的残留率显著低于自然模式,而干质量、P,Mg的残留率差异不显著;复合模式混合处理的分解速率和N,P,K,Ca释放率介于单独分解的细根和草根之间,而Mg释放率则大于单独分解的细根和草根,经过1 a的分解,混合分解对混合处理的分解速率、P,K,Mg的释放有明显的促进作用,对N,Ca的释放影响不显著,在混合分解过程中的不同阶段,表现出来的相互作用形式不同。 相似文献
19.
通过构建我国多花黑麦草主栽品种的SSR标记指纹图谱数据库,以实现对多花黑麦草品种的快速、准确鉴定.本研究利用SSR标记,基于多态性高、稳定性强和连锁群分布均匀的原则,从100对多花黑麦草(Lolium multiflorum Lam.)基因组来源的SSR引物中,筛选出12对引物用来构建了21个多花黑麦草品种(系)的指纹图谱.12对SSR引物共扩增出108种多态性基因型,多态性比率达94.15％,每对引物的基因型从5～22种不等,平均每对引物扩增出9种基因型,多态性信息量(PIC)变幅为0.744～0.934,平均为0.843,此12对引物可以在构建多花黑麦草品种DNA指纹数据库作为核心引物推荐使用.21个多花黑麦草品种(系)基因型间遗传相似性系数在0.4956～0.8571之间,UPGMA聚类分析表明,在相似系数0.69处可将全部材料分为3大类.7对引物在9个品种上具有唯一特征带,采用15-08C单对引物即可将21个多花黑麦草品种完全区分开,该对引物不仅多态性高(PIC=0.934),且具备多个品种的特征谱带.基于该引物建立了供试品种指纹图谱标准模式图,每个品种具有唯一的指纹图谱(带型),为牧草品种的审定和保护以及选配优良杂交组合培育新品种提供了重要的理论依据. 相似文献
20.
Crimson clover (Trifolium incarnatum L.) plus hairy vetch ( Vicia villosa Roth), red clover (Trifolium pratense L.), white clover (Trifolium repens L.), red clover plus white clover, and bermudagrass (Cynodon dactylon [L.] Pers.) were evaluated as cover crops for pecans. Crimson clover plus hairy vetch supplied the equivalent of 101 to 159 kg nitrogen (N)/ha. Red clover plus white clover supplied up to 132 kg N/ha. Either white clover or red clover alone were less effective in supplying N than when grown together. Soil Kjeldahl‐N was usually not affected or increased using the legumes compared to fertilized bermudagrass sod. Soil nitrate (NO3) concentrations during October were occasionally higher in unfertilized legume plots than in bermudagrass plots with March‐applied N. 相似文献