12 research outputs found
The influence of different row spacing and weed control intervals on weed infestation and yield-related traits of American (Gossypium hirsutum L.) and Desi (Gossypium arboreum) cotton
Narrow row spacing has attracted significant attention due to its beneficial impacts on weed management in cotton. This study compared the effects of normal and ultra-narrow row spacing on critical periods of weed control in American (Gossypium hirsutum L.) and ‘Desi’ (Gossypium arboreum) cotton. Two different row spacings (i.e., recommended (75 cm) and ultra-narrow (30 cm)) and three weed control intervals (i.e., weed control at 30, 60 and 90 days after sowing (DAS)) were included in the study. Weedy-check and weed-free treatments were included in the experiment as controls for comparison. ‘Desi’ cotton grown under ultra-narrow spacing recorded the lowest weed density and individual density of Trianthema portulacastarum L., Cyperus rotundus L., Cynodon dactylon L., Echinochloa colona (L.) Link and Digera muricata (L.) Mart. Moreover, ‘Desi’ cotton sown under ultra-narrow spacing with weed-free and weed control at 30 DAS resulted in the highest leaf area index (LAI), leaf area duration (LAD), net assimilation late (NAR), root elongation rate (RER) and root growth rate (RGR) at all sampling dates. Likewise, ‘desi’ cotton sown under recommended row spacing and weed-free conditions produced the highest number of sympodial and monopodial branches, number of flowers and bolls per plant, whereas the highest seed cotton yield of ‘Desi’ cotton was noted under ultra-narrow spacing and weed-free conditions. It is concluded that sowing both cotton types in ultra-narrow row spacing and controlling weeds at 30 DAS will result in lower weed infestation and higher seed cotton yield
Barley-Based cropping systems and weed control strategies influence weed infestation, soil properties and barley productivity
Barley-based cropping systems (BCS) alter barley production by influencing weed infestation rates and soil nutrient dynamics. This two-year field study evaluated the interactive effects of five BCS and five weed control strategies (WCS) on soil properties and the growth and yield of barley. Barley was planted in five different cropping systems, i.e., fallow-barley (FB), maize-barley (MaB), cotton-barley (CB), mungbean-barley (MuB) and sorghum-barley (SB). Similarly, five different WCS, weed-free (control, WF), weedy-check (control, WC), false seedbeds (FS), chemical control (CC) and use of allelopathic water extracts (AWE), were included in the study. The SB system had the highest soil bulk density (1.48 and 1.47 g cm−3 during the period 2017–2018 and 2018–2019, respectively) and lowest total soil porosity (41.40 and 41.07% during the period 2017–2018 and 2018–2019, respectively). However, WCS remained non-significant for bulk density and total soil porosity during both years of the study. Barley with WF had a higher leaf area index (5.28 and 4.75) and specific leaf area (65.5 and 64.9 cm−2 g−1) compared with barley grown under WC. The MuB system under WC had the highest values of extractable NH4-N (5.42 and 5.58 mg kg−1), NO3-N (5.79 and 5.93 mg kg−1), P (19.9 and 19.5 mg kg−1), and K (195.6 and 194.3 mg kg−1) with statistically similar NO3-N in the MaB system under WC and extractable K in the MuB system under FS. Grain yield ranged between 2.8–3.2 and 2.9–3.3 t ha−1 during the period 2017–2018 and 2018–2019, respectively, among different WCS. Similarly, grain yield ranged between 2.9–3.2 and 3.0–3.2 t ha−1 during the period 2017–2018 and 2018–2019, respectively, within different BCS. Among WCS, the highest grain yield (3.29 and 3.32 t ha−1) along with yield-related traits of barley were in WF as compared to WC. Overall, MuB system recorded better yield and yield-related traits, whereas the lowest values of these traits were recorded for FB systems. In conclusion, the MuB system with WF improved soil characteristics and barley yield over other cropping systems. The AWE significantly suppressed weeds and was equally effective as the chemical control. Therefore, MuB and AWE could be used to improve barley productivity and suppress weeds infestation
Soil-Applied boron combined with Boron-Tolerant Bacteria (Bacillus sp. MN54) improve root proliferation and nodulation, yield and agronomic grain biofortification of chickpea (Cicer arietinum L.)
Chickpea is widely cultivated on calcareous sandy soils in arid and semi-arid regions of Pakistan; however, widespread boron (B) deficiencies in these soils significantly decreases its productivity. Soil application of B could improve chickpea yield and grain-B concentration. However, optimizing suitable B level is necessary due to a narrow deficiency and toxicity range of B. Nonetheless, the co-application of B-tolerant bacteria (BTB) and synthetic B fertilizer could be helpful in obtaining higher chickpea yields and grain-B concentration. Therefore, this study optimized the level of soil applied B along with BTB, (i.e., Bacillus sp. MN54) to improve growth, yield and grain-B concentrations of chickpea. The B concentrations included in the study were 0.00 (control), 0.25, 0.50, 0.75 and 1.00 mg B kg−1 soil combined with or without Bacillus sp. MN54 inoculation. Soil application of B significantly improved root system, nodulation, yield and grain-B concentration, and Bacillus sp. MN54 inoculation further improved these traits. Moreover, B application at a lower dose (0.25 mg B kg−1 soil) with BTB inoculation recorded the highest improvements in root system (longer roots with more roots’ proliferation), growth, nodulation and grain yield. However, the highest grain-B concentration was recorded under a higher B level (0.75 mg B kg−1 soil) included in the study. Soil application of 0.25 mg B kg−1 with Bacillus sp. MN54 inoculation improved growth and yield-related traits, especially nodule population (81%), number of pods plant−1 (38%), number of grains plant−1 (65%) and grain yield (47%) compared with control treatment. However, the grain-B concentration was higher under the highest B level (1.00 mg kg−1 soil) with Bacillus sp. MN54 inoculation. In conclusion, soil application of 0.25 mg B kg−1 with Bacillus sp. MN54 inoculation is a pragmatic option to improve the root system, nodule population, seedling growth, yield and agronomic grain-B biofortification of chickpea
Radiation Dose Reduction in the Cardiac Catheterization Laboratory Utilizing a Novel Protocol
ObjectivesThis study reports the results a novel radiation reduction protocol (RRP) system for coronary angiography and interventional procedures and the determinants of radiation dose.BackgroundThe cardiac catheterization laboratory is an important source of radiation and should be kept in good working order with dose-reduction and monitoring capabilities.MethodsAll diagnostic coronary angiograms and percutaneous coronary interventions from a single catheterization laboratory were analyzed 2 months before and after RRP implementation. The primary outcome was the relative dose reduction at the interventional reference point. Separate analyses were done for conventional 15 frames/s (FPS) and at reduced 7.5 FPS post-RRP groups.ResultsA total of 605 patients underwent coronary angiography (309 before RRP and 296 after RRP), with 129 (42%) and 122 (41%) undergoing percutaneous coronary interventions before and after RRP, respectively. With RRP, a 48% dose reduction (1.07 ± 0.05 Gy vs. 0.56 ± 0.03 Gy, p < 0.0001) was obtained, 35% with 15 FPS RRP (0.70 ± 0.05 Gy, p < 0.0001) and 62% with 7.5 FPS RRP (0.41 ± 0.03 Gy, p < 0.001). Similar dose reductions for diagnostic angiograms and percutaneous coronary interventions were noted. There was no change in the number of stents placed or vessels intervened on. Increased dose was associated with male sex, radial approach, increasing body mass index, cine runs, and frame rates. Using a multivariable model, a 48% relative risk with RRP (p < 0.001), 44% with 15 FPS RRP and 68% with 7.5 FPS RRP was obtained.ConclusionsWe demonstrate a highly significant 48.5% adjusted radiation dose reduction using a novel algorithm, which needs strong consideration among interventional cardiology practice
Screening of chickpea genotypes for boron biofortification potential
Background
Malnutrition is a significant threat to mankind and deficiency of important minerals like boron (B) exert negative impacts on human health mostly in developing and least developed countries. Chickpea is an important legume with wide consumption in human diet due to easily digestible dietary protein and grown. Chickpea is mostly grown in arid and semi-arid regions of Pakistan. The B-deficiency in these areas not only decreases chickpea productivity, but also results lowers B concentration in grains. Different chickpea genotypes are capable of perform differently due to their divergent genetic makeup under stressful environmental conditions. Therefore, this field study screened different chickpea genotypes to improve yield and B biofortification.
Methods
For this purpose 20 ‘desi’ (i.e., ‘TG-1430’, ‘Parbat’, ‘TG-1616’, ‘TG-1620’, ‘05A028’, ‘TG-1601’, ‘TG-1623’, ‘Thal-2006’, ‘TG-1218’, ‘TG-1513’, ‘Chattan’, ‘BK-2011’, ‘TG-1500’, ‘NIAB-2016’, ‘GGP-1456’, ‘TG-1618’, ‘TG-1619’, ‘Bittle-2016’, ‘TG-1415’ and ‘Punjab-2008’) and 06 ‘kabuli’ (i.e., ‘TGK-228’, ‘TGK-1767’, ‘TGK-1802’, ‘NOOR-2009’, ‘TGK-1761’ and ‘TGK-1805’) chickpea genotypes were sown under 0 or 1 kg B ha−1 as soil application.
Results
Results indicated that B application improved the growth, nodulation, yield and grains B concentrations of all genotypes; however, genotype significantly differed in their response. Of the 20 ‘desi’ genotypes ‘Punjab-2008’ recorded the highest leaf area index, leaf area duration, crop growth rate, nodulation, yield and related traits under B application. However, genotypes ‘BK-2011’, ‘TG-1500’ and ‘NIAB-2016’ had higher grains B content under 1 kg ha−1 B application. Similarly, ‘kabuli genotypes’, i.e., ‘TGK-1761’ and ‘TGK-1802’ recorded higher nodulation, while ‘NOOR-2009’ had higher leaf area index, leaf area duration, crop growth rate, 1000-grain weight, grain yield and biological yield with 1 kg ha−1 B application compared to the rest of the ‘kabuli’ genotypes included in the study. The highest grain B concentration was recorded for ‘TGK-1767’ among ‘kabuli’ genotypes.
Conclusion
In conclusion, ‘desi’ genotype ‘Punjab-2008’ and ‘kabuli’ genotype ‘NOOR-2009’ should be grown under 1 kg ha−1 B application to get higher productivity and B biofortification. The genotypes which accumulated more B in their seeds should be included in future breeding programs to produce B-rich grains for reducing malnutrition
Iron application improves yield, economic returns and grain-Fe concentration of mungbean
Malnutrition is among the biggest threats being faced globally, and Pakistan is among the countries having high malnutrition rate. Pulses grown in Pakistan have lower amounts of micronutrients, especially iron (Fe) in grains compared to developed world. Biofortification, -a process of integrating nutrients into food crops-, provides a sustainable and economic way of increasing minerals/micronutrients’ concentration in staple crops. Mungbean fulfills protein needs of large portion of Pakistani population; however, low Fe concentration in grains do not provide sufficient Fe. Therefore, current study was conducted to infer the impact of different Fe levels and application methods on yield, economic returns and grain-Fe concentration of mungbean. Mungbean was sown under four levels of Fe, i.e., 0, 5, 10 and 15 kg Fe ha-1 applied by three methods, i) as basal application (whole at sowing), ii) side dressing (whole at 1st irrigation) and iii) 50% as basal application + 50% side dressing (regarded as split application). Iron levels and application methods significantly influenced the allometry, yield, economic returns and grain-Fe concentration of mungbean. Split application of 15 kg Fe ha-1 had the highest yield, economic returns and grain-Fe concentration compared to the rest of Fe levels and application methods. Moreover, split application of 15 kg Fe ha-1 proved a quick method to improve the grain-Fe concentration and bioavailability, which will ultimately solve the Fe malnutrition problem of mungbean-consuming population in Pakistan. In conclusion, split application of Fe at 15 kg ha-1 seemed a viable technique to enhance yield, economic returns, grain-Fe concentration and bioavailability of mungbean
Seed priming with boron and Bacillus sp. MN54 inoculation improves productivity and grain boron concentration of chickpea
Context: The production of chickpea (Cicer arietinum L.) is negatively affected by boron (B) deficiency. In Pakistan, the crop grown under B deficiency produces grains with low B concentration. Application of B-tolerant bacteria (BTB) is a promising option to improve B supply to plants grown under B deficiency.
Aims: This study was focused on determining the appropriate concentration of B for seed priming, and its effects with BTB inoculation on growth, productivity and grain B concentration of chickpea.
Methods: Chickpea seeds were primed in aerated solutions of B concentrations in the range 0.01–0.5% (w/v), with hydroprimed and dry seeds as controls. Concentrations >0.1% proved toxic and seeds failed to germinate. Hence, B was further diluted to concentrations in the range 0.0001–0.1%. Pots containing chickpea seeds were divided into two sets having all B treatments. One set was inoculated with BTB (5 mL per pot of pure Bacillus sp. MN54 culture at 10 9 cfu mL−1); the other set was not inoculated.
Key results: Seed priming with B along with BTB inoculation improved stand establishment, growth, nodulation, yield and grain B concentration of chickpea. Seed priming treatments with B at 0.001% and 0.0001% along with BTB inoculation were most effective for improving stand establishment, seedling growth and grain yield, whereas 0.1% B was more effective for improving grain B concentration.
Conclusions: Seed priming with 0.001% B along with inoculation of Bacillus sp. MN54 improved seed germination, nodulation, yield and grain B concentration of chickpea under B-deficiency conditions.
Implications: Seed inoculation with BTB i.e., Bacillus sp. MN54 coupled with seed priming in 0.001% B solution is a viable option to improve yield and grain B concentration of chickpea grown on B-deficient soils
Synergetic use of biochar and synthetic nitrogen and phosphorus fertilizers to improves maize productivity and nutrient retention in loamy soil
This study was designed to investigate the effect of biochar on maize production and nutrient retention with recommended full and half dose of nitrogen (N) and phosphorus (P) nutrition in loamy soil. In the first study, maize was grown in pots with four levels of biochar (0, 2, 4, and 6 t ha−1) under two levels of NP fertilizer, viz. recommended (200–150 kg NP ha−1) and it’s half (100–75 kg NP ha−1) dose. The prominent improvement in plant roots traits, leaf area, plant growth, morphological and yield-related parameters were observed with addition of biochar at 2 and 4 t ha−1; while, plant height, number of grains per cob, grains and biological yield decreased with biochar addition 6 t ha−1 along with full dose of NP nutrition. In subsequent field studies, two levels of biochar along with control (0, 2, 4 t ha−1) were investigated. The more improvement in root growth, leaf area and crop growth was observed when biochar was applied at 2 t ha−1 with full NP nutrition. Biochar application at 2 t ha−1 with full NP nutrition produced the highest grain yield (6.64 t ha−1); however, biochar addition (2 t ha−1) with half NP nutrition resulted in better grain yield than full dose of NP to enhance maize production as compared with full dose of NP without biochar. Therefore, biochar addition (2 t ha−1) with half-recommended dose of NP prominently improved the maize productivity in loamy soil and serve as better in replacement of full dose of NP fertilizer
Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study
Background
Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.
Methods
This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.
Results
Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51–19.97) than planned admissions (OR: 2.32, 95% CI: 1.43–3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8–51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.
Conclusions
After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies