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1.
Pawitar Singh O. P. Choudhary Pritpal Singh 《Communications in Soil Science and Plant Analysis》2018,49(3):334-343
Most of the crop salt tolerance studies are often conducted in a glasshouse and are limited under field conditions. Therefore, the present research study was conducted under field conditions to evaluate the performance of six wheat cultivars at five salinity levels (EC 0, 3, 6, 9, and 12 dS m?1) in split plot design with three replications. Increasing salinity significantly increased soil pH, electrical conductivity (EC), and sodium adsorption ratio (SAR). Yield parameters of different cultivars were affected more at higher salinity levels than lower in two years. Data over two years revealed that up to EC 9 dS m?1 cultivars PBW 658 and HD 2967 performed ???better on the absolute yield basis but PBW 621 produced ?higher relative yield. At EC 12 dS m?1, PBW 658 produced significantly higher grain yield (4.23 t ha?1) than cultivars HD 2967 (4.11 t ha?1) and PBW 621 (3.99 t ha?1); therefore, should be preferred at salinity more than 9 dS m?1. 相似文献
2.
3.
Hany M. R. Abdel-Latif Mahmoud A. O. Dawood Simon Menanteau-Ledouble Mansour El-Matbouli 《Journal of fish diseases》2020,43(6):651-664
Co-infections commonly arise when two or multiple different pathogens infect the same host, either as simultaneous or as secondary concurrent infection. This potentiates their pathogenic effects and leads to serious negative consequences on the exposed host. Numerous studies on the occurrence of the bacterial, parasitic, fungal and viral co-infections were conducted in various tilapia species. Co-infections have been associated with serious negative impacts on susceptible fish because they increase the fish susceptibility to diseases and the likelihood of outbreaks in the affected fish. Co-infections can alter the disease course and increase the severity of disease through synergistic and, more rarely, antagonistic interactions. In this review, reports on the synergistic co-infections and their impacts on the affected tilapia species are highlighted. Additionally, their pathogenic mechanisms are briefly discussed. Tilapia producers should be aware of the possible occurrence of co-infections and their effects on the affected tilapia species and in particular of the clinical signs and course of the disease. To date, there is still limited information regarding the pathogenicity mechanisms and pathogen interactions during these co-infections. This is generally due to low awareness regarding co-infections, and in many cases, a dominant pathogen is perceived to be of vital importance and hence becomes the target of treatment while the treatment of the co-infectious agents is neglected. This review article aimed at raising awareness regarding co-infections and helping researchers and fish health specialists pay greater attention to these natural cases, leading to increased research and more consistent diagnosis of co-infectious outbreaks in order to improve control strategies to protect tilapia when infected with multiple pathogens. 相似文献
4.
Mohamad Nurul Azman Mohammad Taib Wageeh Abdulhadi Yehye Nurhidayatullaili Muhd Julkapli Sharifah Bee O. A. Abdul Hamid 《Fibers and Polymers》2018,19(2):383-392
Novel acetylation process by substitution of acetic anhydride substitution with hydroxyl groups on nanocellulose (NCC) has been explored to increase its dispersion and interaction in nitrile butadiene (NBR) matrix. The crystallinity index was increased after modification when compared to unmodified NCC, but no significant different with increases of treatment time from 1 hour to 3 hours treatments proven by X-ray diffraction (XRD) results. The Fourier transform infra-red (FTIR) showed the existent of acetyl groups on surface of the NCC after treatment by existent of the peak 1736 cm-1 that attributed to carbonyl groups some peaks were observed at 1430, 1361 and 1248 cm-1 and confirmed on the acetylation process. The nuclear magnetic resonance (NMR) also show the present of acetyl groups by existent of the signal of proton methyl group at 1.90 ppm and new peaks at 5.42, 4.70 and 4.34 ppm, for all ACN samples. The thermal results by thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) showed that the acetylated NCCs were 10 % more thermally stable. Transmission electron microscopic (TEM) results showed that no significant changes were observed due to the acetylation process. The results also showed well distributed of individual NCC after acetylation, this improvement was primarily attributed to uniform dispersion of the ACN-NCC and less aggregated occurred. Due to its hydrophobic characteristics, highly crystalline and nano size, ACN-NCC brought a significant improvement up to 25 % on the mechanical properties of nitrile butadiene (NBR) rubber composites. 相似文献
5.
Fernando D. Brignol Vitor A. G. Fernandes Renata O. Nobrega Camila F. Corrêa Keith Filler James Pettigrew Dbora M. Fracalossi 《Aquaculture Research》2019,50(3):707-716
Nile tilapia juveniles (8.35 ± 0.80 g) were fed on four levels (0.0%; 0.5%; 1.0%; 2.0%, 4.0%) of Aurantiochytrium sp. meal (ALL‐G‐RICH?), a source of docosahexaenoic acid (DHA). The 1% Aurantiochytrium sp. meal diet was compared to a control diet, which contained the same amount of DHA as cod liver oil (CLO) at 1.7% diet. Groups of 25 fish were stocked in 100 L tanks and fed twice daily until apparent satiation, for 57 days, at 28°C. Increasing dietary Aurantiochytrium sp. meal reduced the body retention of DHA and n‐3 polyunsaturated fatty acids (n‐3 PUFA) but increased the body retention of alpha‐linolenic (α‐LNA), linoleic (LOA) and n‐6 polyunsaturated fatty acids (n‐6 PUFA). Fatty acid profile in tilapia muscle was affected by increasing dietary inclusions of Aurantiochytrium sp. meal, with an increase in DHA, α‐LNA, n‐3 PUFA and n‐3 long chain‐polyunsaturated fatty acids (n‐3 LC‐PUFA) but a decrease in monounsaturated fatty acids (MUFA), n‐6 PUFA and n‐6 long‐chain polyunsaturated fatty acids (n‐6 LC‐PUFA). There was a larger body retention of DHA, α‐LNA, LOA, n‐3 PUFA and n‐6 PUFA fatty acids and a higher percentage of DHA, n‐3 PUFA and n‐3 LC‐PUFA in muscle fatty acid profile in fish fed on CLO diets than in those fed on 1% Aurantiochytrium sp. Therefore, Aurantiochytrium sp. meal is an alternative source of DHA for Nile tilapia diets. 相似文献
6.
J. O. Gusmão M. A. C. Danés D. R. Casagrande T. F. Bernardes 《Grass and Forage Science》2018,73(3):717-726
Alternatives need to be addressed for reducing losses in elephant grass (EG; Pennisetum purpureum) silages. Furthermore, smallholders lack information on the nutritional aspects of dairy farms. The aim of this study was to evaluate total mixed ration silage (TMR) combining fresh EG and concentrate ingredients, creating the following treatments: (i) EG silage (control); (ii) EG, corn and soya bean meal; (iii) EG, corn, soya bean meal and molasses; (iv) EG, citrus pulp and soya bean meal; and (v) EG, citrus pulp, soya bean meal and molasses. Five replicates of each treatment were ensiled in 15‐L plastic jars. The fermentation profile, chemical composition, microbial counts and aerobic stability were assessed. Three contrasts were tested, as follows: (i) control vs. TMR; (ii) TMR with corn vs. TMR with citrus pulp; and (iii) TMR with molasses vs. TMR without molasses. Variables were analysed through the PROC MIXED procedure of the SAS at the 5% level. The TMR had better fermentation profile, lower effluent production and longer aerobic stability compared to control. When the effect of corn was compared to citrus pulp among the TMR, silages with citrus pulp showed lower fermentation losses, non‐protein nitrogen and effluent production. The aerobic stability also improved with citrus pulp. Molasses did not affect the fermentation profile. Overall, lactic acid was the primary acid in all TMR. Nitrogen source (e.g., soya bean meal) can be used without compromising the fermentation process. TMR with citrus pulp showed better results than corn. TMR may be an alternative to optimize the use of EG on smallholdings. 相似文献
7.
水稻灭茬机扶茬机构设计与试验 总被引:2,自引:0,他引:2
【目的】解决水稻灭茬机作业时,驱动轮容易将高留茬压倒,引起轮辙处倒茬多,导致水稻秸秆粉碎效果不理想的问题。【方法】研发了一种具有扶禾功能的水稻灭茬机,利用固接于扶茬轮轴上的"L"型扶指,采用扶茬轮轴和粉碎轮轴双侧带轮分流传动方式,实现前置扶茬系统与后置粉碎系统配合作业,使水稻秸秆倒伏的留茬被扶起后立即喂入粉碎室。采用正交设计试验验证灭茬机的田间性能。【结果】水稻灭茬机的前进速度、扶辊转速和扶指宽度均对水稻秸秆粉碎率有显著影响。田间试验的结果表明,机具工作参数的最佳组合为前进速度5.38 km·h~(–1)、扶辊转速160 r·min~(–1)和扶指宽度50 mm,该组合的水稻秸秆粉碎效果最好,粉碎率达到92.52%。【结论】该扶茬机结构简单,对水稻秸秆的扶茬粉碎效果好,在实际生产中能够提升高留茬稻秆的粉碎效率。 相似文献
8.
Kulikova N. A. Zhelezova A. D. Voropanov M. G. Filippova O. I. Plyushchenko I. V. Rodin I. A. 《Eurasian Soil Science》2020,53(6):787-797
Eurasian Soil Science - Application of monoammonium phosphate has been demonstrated to re-immobilize glyphosate sorbed by soil under model laboratory experiment conditions. This effect was most... 相似文献
9.
Nikitin D. A. Ivanova E. A. Zhelezova A. D. Semenov M. V. Gadzhiumarov R. G. Tkhakakhova A. K. Chernov T. I. Ksenofontova N. A. Kutovaya O. V. 《Eurasian Soil Science》2020,53(12):1782-1793
Eurasian Soil Science - Quantitative characteristics of microbial communities in southern agrochernozems of the Stavropol region managed with the use of no-till technology and moldboard plowing... 相似文献
10.
Sychev V. G. Naliukhin A. N. Shevtsova L. K. Rukhovich O. V. Belichenko M. V. 《Eurasian Soil Science》2020,53(12):1794-1808
Eurasian Soil Science - The results of long-term experiments (LTEs) performed at the Geographical Network of experimental stations encompassing major soil types in Russia (soddy-podzolic (Retisols,... 相似文献