绢蒿荒漠草地两种主要植物的生态化学计量特征分析     

范燕敏  武红旗  侯艳娜  艾科拜尔·安外尔  古丽包斯旦·艾尔肯 《新疆农业科学》2018,55(12):2305-2311

【目的】研究退化伊犁绢蒿荒漠草地恢复后,主要植物的生态化学计量特征的变化,为干旱区草地恢复提供理论依据。【方法】以该草地的建群种伊犁绢蒿(Seriphidium transiliense)和伴生种木地肤(Kochia prostrata)为对象,分析两种植物的C、N、P、K含量及计量比以及放牧和封育条件下,两种植物的生态化学计量特征,研究两种植物的养分利用策略以及封育对两种植物的生态化学计量特征的影响。【结果】伊犁绢蒿的P(0.82 g/kg)极显著高于木地肤的P(0.58 g/kg),伊犁绢蒿的N(15.11 g/kg)、K(13.06 g/kg)含量和N/P(22.46)极显著低于木地肤的N(25.14 g/kg)、K(21.17 g/kg)含量和N/P(43.75)。封育改善了荒漠草地植物的生长环境,但与放牧相比,伊犁绢蒿与木地肤的C、N、P、K含量及元素计量比变化不显著。【结论】伊犁绢蒿与木地肤的养分利用策略不同,伊犁绢蒿以吸收利用P为主,木地肤以吸收利用N和K为主,伊犁绢蒿的生长率高于木地肤。封育对荒漠草地两种植物的生态化学计量特征影响不显著。  相似文献   

Assessment of gut microbiota in different developmental stages of Malaysian Mahseer (Tor tambroides)          下载免费PDF全文

Mohamad Zaimin Mohd Nosi  Sharifah Noor Emilia Syed Jamil Fadaak  Muhd Danish Daniel Muhammad  Shumpei Iehata 《Aquaculture Research》2018,49(9):2977-2987

Malaysian Mahseer (Tor tambroides) has a good prospect for aquaculture because of its high market demand. However, there is a scarce information on gut microbiota associated with Malaysian Mahseer unlike other fish species. Therefore, we constructed and compared gut microbiota in different developmental stages (larval, juvenile, fingerling, yearling, and adult) using culture dependent and PCR‐DGGE fingerprinting technique for better understanding of gut microbiota composition associated with T. tambroides. Culturable gut microbiota composition in all developmental stages were composed of β‐ and γ‐Proteobacteria, and Bacilli. Biodiversity analysis of culturable gut microbiota showed that larval, juvenile, and adult stages have higher diversity than fingerling and yearling stages. Ward's linkage cluster analysis showed that culturable gut microbiota composition in larval and juvenile stages were close to adult stages, whereas fingerling and yearling stage composed same cluster. PCR‐DGGE fingerprinting technique showed that unculturable gut microbiota were constituted by α‐and γ‐Proteobacteria, and Actinobacteria. Ward's linkage cluster analysis showed that unculturable gut microbiota composition in both larval and juvenile stages were distinct from other developmental stages. Our results revealed that gut microbiota composition were varied in different developmental stages of Malaysian Mahseer and continuous shifts of gut microbiota from larval to adult stages.  相似文献   

Growth and Physiological Performance of Aerobic and Lowland Rice as Affected by Water Stress at Selected Growth Stages     

Nadzariah Kamarul Zaman  Mohd Yusoff Abdullah  Sariam Othman  Nadzirah Kamarul Zaman 《水稻科学》2018,25(2):82-93

Aerobic rice technology is still new in Malaysia, and information regarding MARDI Aerob 1 (MA1), the first local aerobic rice variety, is still lacking. Therefore, comparative studies were carried out to determine the physiological performance of aerobic rice variety MA1 and lowland rice variety MR253 under water stress given at the panicle initiation, flowering and ripening stages. This experiment was arranged in a randomized complete block design. Stomatal conductance (g_s), chlorophyll a fluorescence (F_v/F_m), leaf relative water content (leaf RWC), and soil moisture content (SMC) as well as yield component parameters such as panicle number, grain yield and 100-grain weight were measured. Results revealed that g_s and leaf RWC for both varieties decreased with depletion of SMC. The correlation study between the physiological parameters and SMC indicated that F_v/F_m was not affected by water stress, regardless of varieties. The yield components (panicle number, grain yield and 100-grain weight) for both varieties greatly decreased when water stress was imposed at the panicle initiation stage. This study showed that the panicle initiation period was the most sensitive stage to water stress that contributed to a substantial reduction in yield for both varieties. Under the aerobic condition (control), MR253 produced higher panicle number, 100-grain weight and yield than MA1. Although MR253 is bred for lowland, it is well adapted to aerobic condition.  相似文献   

Treatment of Cotton by β-Cyclodextrin/Triclosan Inclusion Complex and Factors Affecting Antimicrobial Properties     

Mikhail Novikov  Kwai Lin Thong  Nur Izzurianna Mohd Zazali  Sharifah Bee Abd Hamid 《Fibers and Polymers》2018,19(3):548-560

The efficacy of antimicrobial treatment of cotton fabrics depends on various parameters of the coating process, such as the chemical nature and concentration of the antimicrobial agent, the composition of the crosslinking formulation, and the curing temperature. The inclusion complex of triclosan with β-cyclodextrin (βCD) was synthesized and characterized by FTIR, XRD, NMR, Raman, SEM, and TGA. The minimum inhibitory concentration and minimum bactericidal concentration of the complex against Klebsiella pneumoniae and Staphylococcus aureus were compared to those of its precursor. A multifactorial study included an evaluation of the effects of triclosan complexation with β-cyclodextrin, a comparison between the glyoxal and tetracarboxylic acid as crosslinkers, an investigation of the effect of crosslinker and catalyst concentrations, and a comparison of curing at 120°C and 180°C. The cotton was characterized by FTIR-ATR, the micrographs of treated samples were obtained by SEM and the weight add-on was calculated. The bactericidal properties were determined according to AATCC-147. The correlation between the coating process parameters and the antimicrobial efficacy was determined. The optimal combination leading to the highest weight add-on and the antimicrobial coating that was most durable to multiple detergent washes at an elevated temperature was the use of complexed triclosan grafted onto the cotton in the presence of tetracarboxylic acid, followed by curing at 180°C. The curing temperatures were 120°C (P=0.002) and 180°C (P=0.008), catalysts were 1 % and 2 % aluminium sulfate and sodium hypophosphite (P<0.001), and the crosslinkers were 5 % and 10 % glyoxal and butanetetracarboxylic acid (P<0.001); these parameters significantly enhanced the antimicrobial properties of the treated fabrics. The study showed that βCD did not have antimicrobial activity, while the βCD/triclosan-treated textile exhibited potential antimicrobial properties. Overall, the bactericidal activity of fabrics can be enhanced by using βCD/triclosan with 10 % butanetetracarboxylic acid as a cross-linker and 5 % sodium hypophosphite as a catalyst at a curing temperature of 180°C.  相似文献   

Seasonal deviation effects foliar endophyte assemblage and diversity in <Emphasis Type="Italic">Asparagus racemosus</Emphasis> and <Emphasis Type="Italic">Hemidesmus indicus</Emphasis>     

Riyaz Ahmad Rather  Vijayalakshmi Srinivasan  Mumtaz Anwar 《BMC ecology》2018,18(1):52

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Isolation of Nanocellulose from Water Hyacinth Fiber (WHF) Produced via Digester-Sonication and Its Characterization     

Mochamad Asrofi  Hairul Abral  Anwar Kasim  Adjar Pratoto  Melbi Mahardika  Ji-Won Park  Hyun-Joong Kim 《Fibers and Polymers》2018,19(8):1618-1625

The successful isolation and characterization of water hyacinth fiber (Eichornia crassipes) (WHF) nanocellulose is presented in this study. The novelty was in exploring a wider range of properties of highly purified samples of WHF after each stage of production in more depth. The isolation was accomplished by pulping in a digester and sonication. Morphological changes before and after treatment were demonstrated by scanning electron microscopy (SEM). The lignin and hemicellulose content decreased during chemical treatment. Transmission electron microscopy (TEM) and particle size analyzer (PSA) were used to determine the morphology of WHF after sonication for 1 h. TEM shows that the diameter and length of nanocellulose WHF were 15.61 and 147.4 nm, respectively. The crystallinity index and crystalline domain area significantly increased after chemical treatment. The highest crystallinity index was 84.87 % after an acid hydrolysis process. The increase in crystallinity leads to good thermal stability. Moisture absorption tests of WHF were carried out before and after treatment. The lowest moisture absorption was in the cellulose fiber after sonication (nanocellulose).  相似文献   

Impregnation of zinc oxide mediated chitosan nano-composites on polyester fabric for performance characteristics     

Zulfiqar Ali Raza  Faiza Anwar 《Fibers and Polymers》2016,17(9):1378-1383

Present study dealt with the fabrication of chitosan/zinc oxide nano-composites (CZNCs) using a facile preparation method. The structural features of nano-composites were investigated by using advanced analytical techniques. The developed nano-composites exhibited hexagonal structural pattern with an average particle size of about 51 nm. The developed CZNCs were dispersed in 2-propanol and applied on polyester by using the pad-dry-cure method. The treated fabric specimens were characterized for surface, functional and textile properties including antibacterial activity and (ultra violet) UV- blocking. The nano-composite treated polyester fabric exhibited durable antibacterial, UV- blocking and textile properties with fair whiteness index.  相似文献   

Water Regimes and Humic Acid Application Influences Potato Growth,Yield, Tuber Quality and Water Use Efficiency   总被引：1，自引：0，他引：1  

Mekhled Alenazi  Mahmoud Abady Wahb-Allah  Hesham Saleh Abdel-Razzak  Abdullah Anwar Ibrahim  Abdullah Alsadon 《American Journal of Potato Research》2016,93(5):463-473

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Cryptocaryon irritans recombinant proteins as potential antigens for sero‐surveillance of cryptocaryonosis          下载免费PDF全文

Y Lokanathan  A Mohd‐Adnan  B‐C Kua  S Nathan 《Journal of fish diseases》2016,39(9):1069-1083

Cryptocaryonosis is a major problem for mariculture, and the absence of suitable sero‐surveillance tools for the detection of cryptocaryonosis makes it difficult to screen Cryptocaryon irritans‐infected fish, particularly asymptomatic fish. In this study, we proposed a serum‐based assay using selected C. irritans proteins to screen infected and asymptomatic fish. Eight highly expressed genes were chosen from an earlier study on C. irritans expressed sequence tags and ciliate glutamine codons were converted to universal glutamine codons. The chemically synthesized C. irritans genes were then expressed in an Escherichia coli expression host under optimized conditions. Five C. irritans proteins were successfully expressed in E. coli and purified by affinity chromatography. These proteins were used as antigens in an enzyme‐linked immunosorbent assay (ELISA) to screen sera from experimentally immunized fish and naturally infected fish. Sera from both categories of fish reacted equally well with the expressed C. irritans recombinant proteins as well as with sonicated theronts. This study demonstrated the utility of producing ciliate recombinant proteins in a heterologous expression host. An ELISA was successfully developed to diagnose infected and asymptomatic fish using the recombinant proteins as antigens.  相似文献   

An attempt at implementing a holistic inclusive development model: Insights from Malaysia's land settlement scheme          下载免费PDF全文

Mohd Zufri Mamat  Boon‐Kwee Ng  Suzana Ariff Azizan  Lee Wei Chang 《Asia Pacific viewpoint》2016,57(1):106-120

This paper examines the influences of Malaysia's Federation Land Development Authority (FELDA) scheme in fostering inclusive rural development. Based on the model of holistic inclusive development, the paper investigates the performance of FELDA from four perspectives: social development, industrialisation, modernisation and basic needs. The main findings of the study indicate that, to a large extent, the scheme has successfully stimulated both the social and economic development of the community. Nonetheless, establishing a strong trust, social cohesion and rapport between the public authorities and community remain the main challenges in determining the success of this state‐led agenda. Moreover, keeping traditional values in the modern system will be the key principle for the sustainability of the programme if plans are made to adopt the scheme in other regions.  相似文献