no-P Treatment Research Articles

Fine-root traits are devoted to the allocation of foliar phosphorus fractions of desert species under water and phosphorus-poor environments.

Traits of leaves and fine roots are expected to predict the responses and adaptation of plants to their environments. Whether and how fine-root traits (FRTs) are associated with the allocation of foliar phosphorus (P) fractions of desert species in water- and P-poor environments, however, remains unclear. We exposed seedlings of Alhagi sparsifolia Shap. (hereafter Alhagi) treated with two water and four P-supply levels for three years in open-air pot experiments and measured the concentrations of foliar P fractions, foliar traits, and FRTs. The allocation proportion of foliar nucleic acid-P and acid phosphatase (APase) activity of fine roots were significantly higher by 45.94 and 53.3% in drought and no-P treatments relative to well-watered and high-P treatments, whereas foliar metabolic-P and structural-P were significantly lower by 3.70 and 5.26%. Allocation proportions of foliar structural-P and residual-P were positively correlated with fine-root P (FRP) concentration, but nucleic acid-P concentration was negatively correlated with FRP concentration. A tradeoff was found between the allocation proportion to all foliar P fractions relative to the FRP concentration, fine-root APase activity, and amounts of carboxylates, followed by fine-root morphological traits. The requirement for a link between the aboveground and underground tissues of Alhagi was generally higher in the drought than the well-watered treatment. Altering FRTs and the allocation of P to foliar nucleic acid-P were two coupled strategies of Alhagi under conditions of drought and/or low-P. These results advance our understanding of the strategies for allocating foliar P by mediating FRTs in drought and P-poor environments.

Accumulation of zinc, iron and selenium in wheat as affected by phosphorus supply in salinised condition

Biofortification of zinc (Zn), iron (Fe) and selenium (Se) in crops could be affected by environmental factors such as soil salinity and phosphorus supply levels, as well as by the genotypic effect. Two pot experiments were conducted with one examined the effects of P supply and salinity on plant growth and Zn, Fe and Se uptake in wheat, and the other examined genotypic differences in Zn, Fe and Se accumulation among 20 wheat genotypes. The results of the first pot study showed significant interactive effects between P supply and salinity on Zn, Fe and Se accumulation. Increasing salinity at the same P supply level increased shoot Zn concentrations, but significantly decreased total shoot Zn amount owing to decreased aboveground biomass. An increased accumulation of total shoot Fe and Se in P-added treatments, relative to the no-P treatments, was mainly due to increased aboveground biomass. The results of the second pot study showed substantial genotypic variations in Zn, Fe and Se accumulation; principal component analysis (PCA) suggested that agronomic traits and nutrient accumulation were controlled by independent genetic mechanisms. These results indicated that the amount of P supply is a key factor regulating biomass and accumulation of Zn, Fe and Se in certain saline soils; the sizable genotypic difference in Zn, Fe and Se accumulation observed in salinised conditions has provided potential scope for genetic improvement by breeding strategies.

Influence of Phosphite Supply in the MS Medium on Root Morphological Characteristics, Fresh Biomass and Enzymatic Behavior in Five Genotypes of Potato (Solanum tuberosum L.)

Crop production is threatened by low phosphorus (P) availability and weed interference. Obtaining plant genotypes that can utilize Phosphite (Phi) as fertilizer can supplement phosphates (Pi) while providing an environmentally friendly means of weed control. The study was conducted to determine the tolerance and enzymatic behavior of five potato genotypes to PO3. Explants were regenerated in vitro from two nodal cuttings and cultured on Murashige and Skoog (MS) medium under controlled conditions for 30 days. Matured plantlets were subcultured for 20 days in MS medium containing (0.25, 0.5 mM) Phi and Pi and No-P (-Phi + -Pi). The results showed significant genotypic variation in tolerance indices among the five genotypes. Atlantic showed greater tolerance to Phi, with highest total root length (50.84%), root projected area (75.09%), root surface area (68.94%), root volume (33.49%) and number of root forks (75.66%). Phi induced an increasing trend in the levels of hydrogen peroxide in the genotypes with the least effect in Atlantic. The comprehensive evaluation analysis confirmed the tolerance of Atlantic genotype with this ranking; Atlantic, Longshu3, Qingshu9, Longshu6 and Gannong2. Antioxidant enzyme activities and proline content also increased significantly under Phi and No-P treatments. The results suggested that potato genotypes with larger root systems may be more tolerant to Phi than genotypes with smaller root systems.

Sweet Corn Phosphorus Uptake from Sandy Soil Amended with Anaerobically-digested Manure

ABSTRACT Anaerobic digester development on dairy, poultry, and swine confined animal feeding operations (CAFOs) reduce manure storage, produce energy and are poised to supply a variety of nutrient-rich materials. Field experiments were conducted in the Columbia Basin of South-Central Washington to evaluate the yield response and phosphorous (P) use efficiency of sweet corn (Zea mayes convar. saccharata cv. Sheba) to the application of P from anaerobic-digested manures. Treatments consisted of the application of 0, 10, 20, 40 kg P ha−1 from five sources, three from anaerobic digesters (AD); AD-dairy P fine solids; AD centrifuged poultry solids; and AD dairy-derived struvite-P compared to a commercial poultry fertilizer, commercial mono-ammonium phosphate, and a non-amended control. Sweet corn yields were not significantly different among P amendments or rates of application but were different between years and were greater than the No-P treatment in 2014. Phosphorus recovery efficiency defined as that percentage of applied P recovered by sweet corn averaged 138% among treatments receiving 10 kg P ha−1 and declined to 57% for higher rates of poultry materials and the commercial mono-ammonium phosphate (MAP) in 2013 and declined 50% in 2014 due to lower yields. Although yield was not different the uptake of P among treatments was significantly greater than the unfertilized control. The lack of yield differences among rates of P applied indicates that P was not limiting yield and suggests that under these production conditions the application of 10 kg P ha−1 of any of the amendments was sufficient. Abbreviations: AD: anaerobic digestion; ADD: anaerobic-digested dairy manure; ADP: anaerobic digested poultry manure; ADS: anaerobic-digested struvite; DM – dry matter; MAP – mono ammonium phosphate; PBP a commercial poultry fertilizer; PRD: percent P recovery efficiency difference method; PRB: percent P recovery balance method; PUE: Phosphorus use efficiency; AUE – Agronomic utilization efficiency.

Optical Sensing and Arbuscular Mycorrhizal Fungi for Improving Fertilizer Nitrogen and Phosphorus Use Efficiencies in Maize

Application of fertilizer nitrogen (N) and phosphorus (P) in excess of crop requirement causes nutritional imbalances in soil along with economic and ecological losses. The optical sensors (leaf color chart, chlorophyll meter, and GreenSeeker) help guide real-time N topdressing decisions and arbuscular mycorrhizal fungi (AMF) further improve nutrient uptake from soil. A four-year field study was conducted to improve N- and P-use efficiencies in maize using different optical sensing tools and coating seeds with AMF. The AMF seed coating improved mycorrhizal colonization in soil. Higher mycorrhization was observed in no-P treatment; however, P fertilization and mycorrhiza inoculation diminish the effect as growth progressed from 30 to 60 days after sowing. The mycorrhizal inoculation increased grain yield by 17.1% in no-N treatment; however, the response diminishes with N fertilization. The optical sensing–based N management sustained grain yield, total N uptake, and root and plant dry weight equivalent to the soil test–based fertilizer N recommendation with the less use of 30 kg N ha−1. The respective improvement in agronomic and recovery efficiencies of applied fertilizer N up to 38.6 and 34.9% highlights the potential of optical sensing tools and the inability of soil test–based N recommendation for precision N management. Mitigated greenhouse and nitrous oxide emissions respectively by 30.7% and 29.7% further underline the prominence of replacing soil test N recommendations with optical sensing–guided N top-dressings. Sufficient inherent soil P restricts the AMF benefits in improving P-use efficiencies in maize.

Optimizing Soil and Fertilizer Phosphorus Management According to the Yield Response and Phosphorus Use Efficiency of Sugarcane in Southern China

The objective of this study was to determine the suitable range of available phosphorus (P) and fertilizer application rate in a sugarcane-growing region with red soil in southern China. Thirty-five monitoring sites were selected to investigate the soil available P in relation to crop yield, P-use efficiency (PUE) and soil total P under four different P rates. Compared with the no-P treatment, all three treatments involving fertilizer P presented sugarcane yields increased to varying extents, with an average increase of 17.6–25.8%. The yield-increasing effects and PUE in each P treatment decreased with increasing soil available P. The agronomic critical values of available P for sugarcane according to the linear-linear, linear-plateau and Mitscherlich models were 27.7, 41.5 and 17.0 mg kg−1, respectively. When the response of the yield-increasing effects of P fertilizer to soil available P and the agronomic critical values of the three models were combined, the linear-linear model exhibited the best fit. An observable change occurred in the available P response to total P. After the change point, the available P increased dramatically with increasing total P, possibly leading to decreased PUE or even triggering water pollution. Therefore, 28–50 mg kg−1 is the suggested range of suitable soil available P for the sugarcane-growing region. In addition, when the soil P budget and current relatively high level of available P are considered, applications of P fertilizer at 120 kg P2O5 ha−1 (1/2 the conventional P fertilizer rate) are recommended in this region.

Influence of long-term phosphorus fertilisation history on the availability and chemical nature of soil phosphorus

Data on the dynamics and fate of phosphorus (P) under low soil-test P (STP) conditions is essential for the development of cropping strategies with a high P use efficiency. This study examined the effects of long-term (20 years) mineral and organic fertiliser P applications on a P-depleted sandy loam soil in Denmark. The cycling of P was examined by use of P budgets (inputs-offtake), chemical P extractions, 33P isotopic exchange kinetics (IEK), and solution 31P nuclear magnetic resonance (NMR) spectroscopy on NaOH-EDTA extracts.Recovery of applied P in the topsoil was smaller for animal slurry P compared with mineral fertiliser P. The budgets suggest deeper soil layers play an important role for the cycling of P. Resin-extractable P (2 to 17 mg kg−1), Olsen-P (7 to 16 mg kg−1) and E1min (1 to 6 mg kg−1) were correlated with the P budgets. Between 63 and 77% of total inorganic P was not exchangeable in a period of three months (E>3months), with the lowest value observed in no-P treatment N1K1. The data show that a redistribution of exchangeable P had taken place under the influence of a strongly negative P budget. Microbial P (6 to 18 mg kg−1) increased under animal slurry inputs compared with mineral fertiliser applications (p < 0.05). All soils were dominated by phosphomonoesters and orthophosphate (98 to 99% of the NMR signal). Concentrations of orthophosphate (86 to 135 mg kg−1) varied significantly between treatments (p < 0.01), whereas forms of organic P remained largely unchanged.The results demonstrate that P applications increased the amount of P that is potentially available for plants, irrespective of input form. Nevertheless, most P applied in excess of crop uptake resulted in an increase of the amount of P that is slowly exchangeable. Under low soil test P conditions such as in the current trial, fertiliser P applied in excess of plant demand that accumulates in soil would thus only be partially available for crops in subsequent years. On the other hand the data suggests that soil P reserves may be utilised for crop growth, but at the low soil P intensity plant access to P will have to be managed carefully.

Effects of 3-nitrooxypropanol on enteric methane production, rumen fermentation, and feeding behavior in beef cattle fed a high-forage or high-grain diet1.

The objective of the study was to determine whether feeding a diet supplemented with 3-nitrooxypropanol (3-NOP) affects feeding behavior altering intake and rumen fermentation. Two experiments were conducted with 9 rumen-cannulated beef steers in a replicated 3 × 3 Latin square design where animals received a high-forage or high-grain diet. Treatments were 1) a basal diet (CON), the CON diet supplemented with 3-NOP (dNOP; 100 mg/kg in dietary DM or 1 g/d), or the CON diet with 3-NOP (1 g/d) infused into the rumen (infNOP). Each experimental period consisted of 14-d diet adaptation and 7-d sample collection. A 7-d washout period was provided between experiment periods. All data were analyzed as a Latin square design using Mixed Procedure of SAS. In Exp. 1 (high-forage diet), methane yield (measured by the Greenfeed system) was lowered by 18% (18.6 vs. 22.7 g/kg DMI; P < 0.01) by dNOP compared with CON. Rumen fermentation was altered similarly by both NOP treatments compared with CON where dNOP and infNOP increased (P < 0.01) rumen pH at 3 h and decreased (P < 0.01) proportion of acetate in total VFA. However, DMI, feed consumption rate (0 to 3, 3 to 6, 6 to 12, and 12 to 24 h after feeding), particle size distribution of orts, and feeding behavior (videotaped for individual animals over 48 h) were not affected by dNOP and infNOP compared with CON. In Exp. 2 (high-grain diet), methane production was not affected by dNOP or infNOP compared with CON. Dry matter intake, feed consumption rate, particle size distribution of orts, and feeding behavior were not altered by dNOP and infNOP compared with CON. However, both dNOP and infNOP affected rumen fermentation where total VFA decreased (P = 0.04) and acetate proportion in total VFA tended to decrease (P = 0.07) compared with CON. In conclusion, dietary supplementation of 3-NOP did not affect feeding behavior of beef steers fed a high-forage or high-grain diet. However, rumen fermentation was similarly changed when 3-NOP was provided in the diet or directly infused in the rumen. Thus, observed changes in rumen fermentation with 3-NOP were not due to changes in feeding behavior indicating no effects on the organoleptic property of the diets. In addition, according to small or no changes in DMI in both experiments and relatively small changes in rumen fermentation in Exp. 2, a greater dosage level of 3-NOP than 100 mg/kg (dietary DM) may need further examination of its effects on feeding behavior of beef cattle.

Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters: P135. Probability of severe frailty development among operative and nonoperative adult spinal deformity patients: an actuarial survivorship analysis over a three-year period

BACKGROUND CONTEXT Frailty, believed to be a true measure of physiological age, is a relatively new medical concept. Little is known of how frailty progresses, relative to a patient's age or disability status. Operative intervention, often associated with significant disability improvements, may play a role in frailty maintenance or progression among adult spinal deformity (ASD) patients. PURPOSE Investigate the probability of severe frailty development among operative (Op) and nonoperative (Nop) ASD patients over a 3-year period. STUDY DESIGN/SETTING Retrospective re of a prospective ASD multicenter database. PATIENT SAMPLE A total of 556 ASD patients. OUTCOME MEASURES ASD Frailty Index. METHODS Adult spinal deformity patients (coronal scoliosis ≥20°, SVA ≥5 cm, pelvic tilt ≥25°, or T2-12 kyphosis ≥60°) >18y/o, with baseline (BL) frailty scores were included. Frailty is scored from 0 to 1 (no frailty: 0.5). Patients were stratified by Op and Nop treatment, and propensity matched by BL age, Charlson score (CCI) and frailty. Independent and paired t -tests compared frailty between treatment groups and BL, 1 year, 2 year, and ≥3 year follow-up (f/u). An actuarial Kaplan–Meier survivorship analysis, adjusting for patients lost to follow-up, determined probability of severe frailty development at all f/u intervals. Log Rank (Mantel-Cox) analysis determined significant variance in survivorship analysis probabilities between Op and Nop. Multivariate Cox Regressions gauged the effect of sagittal alignment, patient and surgical details on severe frailty development. RESULTS A total of 556 matched patients were included (278 Op, 278 Nop). No differences between age (53.3vs. 55.4), BMI (26.1vs. 25.8), CCI (1.12vs. 1.18), frailty (0.22vs. 0.22) or race were observed (all p>.05). Op patients were less female (77.2% vs. 87.8%, p=.001). Operative cohort surgical approaches included 0.4% anterior, 68.1% posterior, 31.5% combined; 14.5% had staged procedures, 65.5% underwent osteotomies, mean operative time was 363.9 minutes, mean EBL was 1442.9ccs, mean LOS was 7.24days, mean levels fused was 5.3 anteriorly, 10.6 posteriorly. Op patients exhibited decreased frailty at all f/u intervals compared to BL frailty (BL:0.22vs year 1: 0.17; year 2: 0.15; year 3 0.16, all p CONCLUSIONS For operative and nonoperative ASD patients with similar baseline age, comorbidity and frailty status, Op patients exhibited improved frailty at all follow-up intervals compared to Nop patients and baseline frailty status. Nop patients were more likely to develop severe frailty, and at a quicker rate in comparison to Op patients. Severe SVA deformity and thoracic coronal curvature at 6 week follow-up significantly predicted severe frailty development, indicating surgical deformity correction plays a significant role in frailty remediation and maintenance.

Molecular Evolution and Association of Natural Variation in ZmARF31 with Low Phosphorus Tolerance in Maize.

Low-phosphorus (P) stress is one of the major factors constraining plant growth and yield. Improving plant tolerance to P starvation through molecular breeding is an efficient alternative to increase grain production. In the study, 331 diverse maize inbreds were used to detect nucleotide diversity and favorable alleles of ZmARF31, which plays a key role in low P responses and root architecture regulation. Significant phenotypic variation was found in each of 11 tested traits under both P and no-P treatments, and 30 single nucleotide polymorphisms (SNPs) and 14 insertion–deletions (InDels) were detected in ZmARF31 among the 331 maize inbreds. The 5′-untranslated region (UTR) of ZmARF31 showed a small linkage disequilibrium (LD) block under significant purifying selection, whereas the 3′-UTR showed the most abundant diversity and a larger LD block. Thirty, fourteen, and nine natural variations were identified in ZmARF31 that were associated with P-deficiency-tolerance traits (P ≤ 0.01) by using the general linear model (GLM), GLM incorporated with population structure, and mixed linear model, respectively. Four SNPs were significantly associated with the total dry weight (TDW) in the three models, of which SNPs S410 and S462 were located in a complete LD block. A further verification conducted in a recombinant inbred line population revealed that favorable allele G/G of non-synonymous mutation S410 and favorable allele with a 38 bp insertion of InDel S1442 exhibited positive genetic effects on the TDW and total root tips, respectively. Expression analysis further confirmed that ZmARF31 was highly expressed in the roots of low-P-tolerant inbred 178. The protein encoded by ZmARF31 was located both in the nucleus and cytoplasm. Haplotypes carrying more favorable alleles showed a greater effect on phenotypic variation than single loci. Such haplotypes should be helpful to develop valuable genetic markers and perform maize molecular breeding.

Response of Olsen-P to P balance in yellow soil upland of southwestern China under long-term fertilization.

Based on a long-term fertilization experiment in Guizhou Province, we explored the relationships between the soil available phosphorus (Olsen-P), soil apparent P balance and P application rate in order to quantify the best application rate of P fertilizer in yellow upland soil of southwestern China. Moreover, the response curve of crop yield to soil Olsen-P was fitted by Mitscherlich equation to determine the critical content of Olsen-P for crop yield. The results showed that the long-term application of P fertilizer could significantly increase the content of soil Olsen-P, and the increasing rates of Olsen-P across different treatments could be mainly explained by the application rate of P fertilizer. Under no-P treatment, the soil P content was in a deficient state for each year, while it displayed a surplus state in the treatments with P fertilizer, and the crop P uptake and P accumulation were found the highest under MNPK treatment. In contrast to single application of chemical fertilizer treatment (NPK), the combined application of organic fertilizer and chemical fertilizer (1/4 M+3/4 NPK, 1/2 M+1/2 NPK) could enhance crop P uptake and improve accumulative P use efficiency. The soil apparent P balance was significantly (P<0.05) correlated with soil Olsen-P. With average P accumulation of 100 kg·hm-2, the soil Olsen-P increased by 16.4, 13.0 , 21.4 , and 5.6 mg·kg-1 in the treatments of MNPK, 1/4 M+3/4 NPK, 1/2 M+1/2 NPK, and NPK, respectively. The result showed that combined application of organic fertilizer and chemical fertilizer could effectively increase the soil Olsen-P content, and the critical value of soil Olsen-P was 22.4 mg·kg-1 in yellow upland soil of southwestern China. The soil P balance and Olsen-P content were significantly (P<0.01) correlated with the annual P application rate. When the amount of average P application was 33.3 kg P·hm-2·a-1, the budgets of soil P balance remained stable, and the application rate of P fertilizer corresponding to the critical value of soil Olsen-P for crop yield was 45.9 kg P·hm-2·a-1. The content of soil Oslen P was mainly affected by the P fertilizer input amount. When the average P application rate was 45.9 kg P·hm-2·a-1, higher crop yield and P fertilizer efficiency would be achieved. When the average P application rate was greater than 45.9 kg P·hm-2·a-1, crop yield showed no response to P fertilizer input, but resulted in a large amount of P surplus in soil, thereby increasing the environmental risk of soil P loss. The long-term application of manure resulted in a higher increase of Olsen-P than the single chemical P ferti-lizer.

Vitamin A affects the expression of antioxidant genes in bovine mammary epithelial cells with oxidative stress induced by diethylene triamine-nitric oxide

The considerable increase in oxygen requirements due to the high metabolic rate of the bovine mammary epithelial cells (BMEC) during lactation results in an augmented production of reactive nitrogen species (RNS), such as nitric oxide (NO), which may expose cows to increased oxidative stress. Vitamin A (VA) has been shown in several studies to enhance the antioxidant defence system against oxidative stress, but whether the reason is related to a reduced NO production remains unclear. Diethylene triamine-nitric oxide polymer (NOp) is a type of NO-generating compound, which is safe, efficacious, and releases NO over a long period. The current study was conducted to investigate the effect of VA on the antioxidant function in BMEC and the underlying mechanism by discussing the protection of VA on NO-induced oxidative stress of BMEC. The experiment was conducted using a single-factor completely randomized arrangement. Primary BMEC were isolated from the mammary glands of Holstein dairy cows. The third generation cells were randomly divided into four equal groups with six replicates each. Each group received different combinations of VA and NOp treatment as follows: controls (without VA and NOp), NOp treatment alone, VA treatment alone, and VA and NOp treatment together. The lysates were collected to evaluate the activities of glutathione peroxidase (GPx) and thioredoxin reductase (TrxR) and the contents of reactive oxygen species (ROS) and malondialdehyde (MDA), and the cell-free supernatants were collected to analyze selenoprotein P (SelP) content, inducible nitric oxide synthase (iNOS) activities and nitric oxide (NO), interleukin-1 (IL-1), interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α) contents. The results suggested that compared to the control, the cell proliferation, the activity of the antioxidants GPx and TrxR, the content of SelP and the antioxidant gene expressions of GPx1, GPx4, and TrxR1 were significantly decreased (P < 0.05), and the contents of ROS and MDA, the activity of iNOS, the contents of NO and IL-1, IL-6, TNF-α, and their mRNA expressions were increased dramatically in the NOp treatment alone group (P < 0.05), but the opposite changes were observed in the VA treatment alone group. Compared to the NOp treatment alone, the VA and NOp treatment together significantly improved cell proliferation, the activities of the antioxidants GPx and TrxR, and the gene expressions of GPx1 and TrxR1, and dramatically decreased the contents of ROS and MDA, the activity of iNOS, the contents of NO and IL-1, IL-6, TNF-α and their mRNA expression levels (P < 0.05). The present research suggests that VA can improve the antioxidant function of BMEC and protect the cells from experiencing the NOp-induced oxidative stress by regulating antioxidant gene expression. The probable mechanism is that VA can reduce the activity of iNOS and its mRNA expression by down-regulating of the expression of IL-1, IL-6, and TNF-α to reduce NO production. However, the exact mechanism warrants future exploration.

Growth and productivity of wheat affected by phosphorus-solubilizing fungi and phosphorus levels

Phosphorus (P) availability limits crop growth in most of cultivable soils in north-west India. The beneficial rhizosphere microorganisms such as phosphate-solubilising fungi (PSF) were found to increase P availability in soil and improve crop yields. In view of this, field experiments were conducted during 2009-2011 to evaluate the effect of seed inoculation with PSF ( Penicillium bilaii ) at different rates of fertilizer P on P content in leaves and grain yield of irrigated wheat in India. The soil was low in Olsen P at the Bathinda site and medium at the Ludhiana site. In no-P treatment, PSF significantly increased grain yield by 12.6% over non-inoculated control. The effect of PSF on grain yield was generally more pronounced in a soil with low Olsen-P compared to medium Olsen-P level. Inoculation of PSF along with 50% P fertilizer increased wheat yield equivalent to 100% P with no PSF. Spike density was significantly higher in PSF + 50% P than all the other treatments. There is need to study a long-term effect of Penicillium bilaii on P-fertilizer saving in wheat on soils varying in P availability, pH and P fixation capacity for different wheat-based cropping systems.

On-farm trials of optimal fertilizer recommendations for the maintenance of high seed yields in winter oilseed rape (Brassica napus L.) production

Mineral fertilizer plays an important role in the maintenance of high rapeseed yields during oilseed rape (Brassica napus L.) production. On-farm experiments at 60 sites throughout the Yangtze River Basin in China were conducted for 2 years to evaluate the effects of the recommended fertilization rates (180 kg N ha−1, 90 kg P2O5 ha−1, and 120 kg K2O ha−1) on the rapeseed yield, and three indices of soil nutrient supply were adopted to estimate the yield responses to fertilizer recommendation. The results showed that the average contributions of nitrogen (N), phosphorus (P) and potassium (K) fertilizer to seed yield were 40.4, 23.1 and 11.5%, respectively. Compared with the farmers’ fertilization practices (FFP), the recommended fertilization significantly enhanced the seed yield by 29.1% on average. The relationships between plant-available soil nutrient supply, seed yields of the nutrient omission treatments and the yield responses to fertilization were significant, rather than the results of soil testing. With plant-available soil nutrient supplies and seed yields increasing, the yield responses and fertilizer use efficiencies decreased. When the seed yields of no-N and no-P treatments were less than 2000 kg ha−1 and 1500 kg ha−1, the recommended fertilizer rate was beneficial for achieving high seed yield and high efficiency. As defined in our study, the recommended fertilization rates could be used as the regional mean optimal rates (RMOR) of fertilization for winter oilseed rape in the Yangtze River Basin. Partial adjustments according to crop nutrient uptakes and seed yields of the nutrient omission treatments will be feasible for the sites where they were nonresponsive to RMOR.

Non-operative management of blunt liver trauma in a level II trauma hospital in Saudi Arabia

Background:To evaluate our experience with non-operative management of blunt liver trauma at a level II trauma hospital in the Kingdom of Saudi Arabia.Materials and Methods:We prospectively evaluated 56 patients treated for blunt liver trauma at our hospital over a 4-year period (April 2008 to April 2012). Patients who were hemodynamically stable [non-operative group I (NOP)] were treated conservatively in the intensive or intermediate care unit (ICU or IMCU). Patients who were hemodynamically unstable or needed laparotomy for other injuries were treated by urgent laparotomy [operative group II (OP)]. All NOP group patients had computed tomography (CT) of the abdomen with oral and intravenous contrast. Injuries grades were classified according to the American Association for the Surgery of Trauma (AAST). Follow-up CT of the abdomen was performed after 2 weeks in some cases.Results:A total of 56 patients were treated over a 4-year period. Twenty patients (35.7%) were treated by immediate surgery. NOP group of 36 patients (64.3%) were managed in the ICU by close monitoring. Surgically treated group had more patients with complex liver injury (90% versus 58.3%), required more units of blood (6.05 versus 1.5), but had a longer hospital stay (16.6 days versus 15.1 days). None of the patients from the non-operated group developed complications nor did they need operation. The only mortality (in two patients) was in the operated group.Conclusion:The NOP treatment is a safe and effective method in the management of hemodynamically stable patients with blunt liver trauma. The NOP treatment should be the treatment of choice in such patients whenever CT and ICU facilities are available.

Dynamics of Soil and Grain Micronutrients as Affected by Long-Term Fertilization in an Aquic Inceptisol

Micronutrient status in soils can be affected by long-term fertilization and intensive cropping. A 19-year experiment (1990–2008) was carried out to investigate the influence of different fertilization regimes on micronutrients in an Aquic Inceptisol and maize and wheat grains in Zhengzhou, China. The results showed that soil total Cu and Zn markedly declined after 19 years with application of N fertilizer alone. Soil total Fe and Mn were significantly increased mainly due to atmospheric deposition. Applications of P and organic fertilizer with incorporation of straws resulted in dramatic increases in soil total Cu, Zn, Fe, and Mn. Soil diethylenetriamine pentaacetic acid (DTPA)-extractable Cu in all treatments sharply decreased from initially 1.12 to about 0.8 mg kg −1. The treatments with organic fertilizer had the highest soil DTPA-extractable Cu, Zn, Fe, and Mn after 19 years of cropping and fertilization, thus demonstrating the important role of organic fertilizer application in improving available micronutrient status. Cu and Zn contents in wheat grains in the no-P treatments were significantly higher than those of the treatments with P application. In addition, Fe and Mn contents in wheat grains were positively correlated with their soil DTPA-extractable concentrations. These indicated that the long-term application of organic fertilizer resulted in significant increases in soil total and available micronutrient concentrations and remarkable reduction in wheat grain Cu and Zn contents, which was due to high soil available P.

천연물 제초제 개발을 위한 전식물체 수준의 경엽처리 검정법 확립

본 연구는 식물정유의 활용과 개발을 포함한 천연물 제초제의 개발을 효과적으로 추진하기 위한 방안으로서 식물정유 성분의 특성이 고려된 개선된 전식물체(whole-plant) 검정법을 확립하기 위해 수행되었다. 잡초 4초종을(피, 바랭이, 자귀풀, 어저귀) 이용하는 전식물체 경엽살포 검정법은 검정 화합물 량이 충분할 경우, 전식물체 생장점 점적처리법은 검정화합물이 미량일 때 추천할 수 있는 방법으로 판단되었다. 각 식물정유 처리시 초기 처리농도는 <TEX>$2,500{\sim}5,000{\mu}g\;mL^{-1}$</TEX> 수준이 필요하였으며 계면활성제는 Tween 20 보다 NOP를 첨가하였을 경우에 보다 높은 살초활성을 나타내었다. 식물정유와 같이 휘발성이 있는 천연물의 활성을 평가하기 위해서는 약제를 처리한 후 과습 상태에 일정시간 두면 제초활성 발현이 증진되었다. 또한 전식물체 생장점 점적처리법은 경엽살포 검정법에 비해 약 1/100의 약제처리량(부피), 약 1/200의 성분량(무게)에서도 살초효과의 검정이 가능하였다. This study was carried out to establish an improved bioassay system, whole-plant bioassay which is more effective in developing natural herbicides for foliar treatment such as herbicidal essential oils. Two bioassay systems using four weed species (Echinochloa crus-galli, Digitaria sanguinalis, Aeschynomene indica, and Abutilon theophrasti), spraying method and spotting method, were established. Spraying method is applicable if the amount of test compounds is enough, while spotting method is useful for the small amount of test compounds. The initial application rate was desirable at <TEX>$2,500{\sim}5,000\;{\mu}g\;mL^{-1}$</TEX>. Herbicidal activities were higher in the NOP treatment when compared to the Tween 20 treatment. To efficiently evaluate volatile compounds such as essential oils, if the compound-treated pots were incubated in dew chamber for about 10hrs, better results were obtained in the degree and stability of herbicidal responses. When the efficiency of bioassay systems established in this study was compared, the spraying method was minimized four times to the conventional method that has beed used for screening of synthetic compounds in KRICT. On the other hand, in the spotting method, screening for development of a natural herbicides was possible even in level of 1/100 test volume and 1/200 amounts of test compound compared to the spraying method.

Localized application of soil organic matter shifts distribution of cluster roots of white lupin in the soil profile due to localized release of phosphorus.

Phosphorus (P) is a major factor controlling cluster-root formation. Cluster-root proliferation tends to concentrate in organic matter (OM)-rich surface-soil layers, but the nature of this response of cluster-root formation to OM is not clear. Cluster-root proliferation in response to localized application of OM was characterized in Lupinus albus (white lupin) grown in stratified soil columns to test if the stimulating effect of OM on cluster-root formation was due to (a) P release from breakdown of OM; (b) a decrease in soil density; or (c) effects of micro-organisms other than releasing P from OM. Lupin plants were grown in three-layer stratified soil columns where P was applied at 0 or 330 mg P kg(-1) to create a P-deficient or P-sufficient background, and OM, phytate mixed with OM, or perlite was applied to the top or middle layers with or without sterilization. Non-sterile OM stimulated cluster-root proliferation and root length, and this effect became greater when phytate was supplied in the presence of OM. Both sterile OM and perlite significantly decreased cluster-root formation in the localized layers. The OM position did not change the proportion of total cluster roots to total roots in dry biomass among no-P treatments, but more cluster roots were concentrated in the OM layers with a decreased proportion in other places. Localized application of non-sterile OM or phytate plus OM stimulated cluster-root proliferation of L. albus in the localized layers. This effect is predominantly accounted for by P release from breakdown of OM or phytate, but not due to a change in soil density associated with OM. No evidence was found for effects of micro-organisms in OM other than those responsible for P release.

Phosphorus Changes and Sorption Characteristics in a Calcareous Soil Under Long-Term Fertilization

Knowledge of phosphorus (P) behavior in long-term fertilized soils is essential for programming fertilization practices and for sustaining environmental quality. The long-term (1984–1997) effects of various fertilization treatments on P changes and sorption isotherms as well as the relationship of soil properties to P sorption and P forms were evaluated in an Ustic Isohumisol, a calcareous soil, on the Loess Plateau, China. Compared to 1984, after 13 years of crop production, total soil P in the no-P treatments (control and N treatment) decreased by 5%–7%, but in the phosphorus fertilizer alone (P), nitrogen and phosphorus fertilizers in combination (NP), manure alone (M), and nitrogen and phosphorus fertilizers and manure in combination (NPM) treatments, it increased by 22%, 19%, 28%, and 58%, respectively. Residual fertilizer P was found mainly in NH 4Ac-soluble P (Ca 8-P), followed by NaHCO 3-soluble P (NaHCO 3-P), and NH 4F-soluble P (Al-P). Phosphorus sorption in the soils with different fertilization practices fit the Langmuir equations. Phosphorus sorption capacity in the no-P treatments increased, whereas it decreased in the P-included treatments (P, NP, and NPM treatments). Phosphorus sorption maximum (Q m) was significantly and negatively correlated to inorganic P including NaHCO 3-P, Ca 8-P, NaOH-Na 2CO 3-soluble P (Fe-P), and Al-P (P ≤ 0.01). Moreover, long-term fertilization increased soil organic carbon in the NP, M, and NPM treatments and decreased pH in the NP and NPM treatments. Thus, the ability of the soil to release sorbed P to the environment increased under long-term P fertilization.

Phosphorus input-output on an ultisol cropped to upland rice in West Africa

A long-term (1993-98) experiment was conducted in Man, Cote d'Ivoire, West Africa, to study the effect of four proved upland rice cultivars to direct phosphorus (P) in 1993 and to residual P in 1994, 1995, 1996 and 1998, applied at five rates only once in 1993. The soil at the site in the humid forest zone is an Ultisol. The four rice cultivars were WARDA-bred cultivars WAB56-125, WAB56-104 and WAB556-50 and check IDSA6, and the five rates of P fertilizers, applied as triple superphosphate were (0, 45, 90, 135 and 180 kg P/ha). All plots received a uniform application of N (applied as urea at 100 kg/ha) and K (applied as KCl at 100 kg/ha). At harvest, rice grain and straw yields were recorded and total P uptake in rice biomass was computed by analysing the P content of the grain and straw samples. The P input-output value (amount of P applied and amount of P taken up in the grain plus straw in five crops) was negative in the no-P treatment but positive in treatments where P fertilizer was added. The results showed that in five crops, only a small fraction of the applied P fertilizer was removed by the rice crop, which varied from 5.5-9.4%, and this value decreased with the increase in the rate of P applied. In 1998, however, after 5 years of successive cropping, available P in the soil was found to be similar and not affected by the rate of P fertilizer applied in 1993