HIỆN TRẠNG CANH TÁC VÀ THÀNH PHẦN CÔN TRÙNG TRÊN CÂY CÓI (Cyperus malaccensis Lam) TẠI HUYỆN CÀNG LONG, TỈNH TRÀ VINH

2020 ◽  
Vol 129 (3D) ◽  
Author(s):  
Nguyễn Hồng Ửng ◽  
Đặng Hòa Thái ◽  
Phan Quốc Nam ◽  
Nguyễn Hồng Nương ◽  
Nguyễn Thị Hồng Thủy
Keyword(s):  
Cyperus Malaccensis

Nghiên cứu này nhằm xác định  hiện trạng canh tác và thành phần côn trùng trên ruộng cói tại huyện Càng Long, tỉnh Trà Vinh. Phương pháp nghiên cứu gồm điều tra 100 nông hộ đang canh tác cây cói của huyện Càng Long và khảo sát ngoài đồng. Kết quả cho thấy mỗi nông hộ có 2-3 lao động với nhiều kinh nghiệm canh tác (6-20 năm). Trong kỹ thuật canh tác, 100% nông hộ chỉ sử dụng phân hóa học với liều lượng trung bình 280N + 140P2O5 + 110 K20 (kg ha-1) và không sử dụng phân hữu cơ. Dịch hại quan trọng đối với cây cói là sâu đục thân (98% nông hộ) và bệnh đốm vàng (100% nông hộ) với khả năng làm chết cây cói ở tỉ lệ cao và xuất hiện quanh năm và 100% nông hộ sử dụng thuốc hóa học để quản lý. Cây cói cho thu nhập tương đối cao và phần lớn nông hộ không có ý định chuyển sang cây trồng khác (95% nông hộ). Việc canh tác cây cói có nhiều thuận lợi như nông hộ có nhiều kinh nghiệm, thu nhập ổn định và đất đai thích hợp, khó khăn chủ yếu là vấn đề dịch hại và thiếu nước vào mùa khô. Kết quả cũng cho thấy có 11 loài côn trùng gồm 08 loài côn trùng gây hại (0,04 – 51,5 con/m2) và 03 loài côn trùng có ích (0,26 - 1,63 con/m2).

Phytochemical investigation of Cyperus malaccensis subsp. monophyllus

2019 ◽  
Author(s):  
M Hibi ◽  
N Abe ◽  
M Haba ◽  
T Tanaka ◽  
H Murata ◽  
...  
Keyword(s):  
Phytochemical Investigation ◽  
Cyperus Malaccensis

Shewanella cyperi sp. nov., a facultative anaerobic bacterium isolated from mangrove sediment

2021 ◽  
Vol 71 (8) ◽  
Author(s):  
Qi Zhang ◽  
Guohong Liu ◽  
Manik Prabhu Narsing Rao ◽  
Rong Tang ◽  
Shang Yang ◽  
...  
Keyword(s):  
Type Strain ◽  
Sequence Similarity ◽  
Mangrove Sediment ◽  
Rrna Gene ◽  
Similar Species ◽  
Polar Lipid Profile ◽  
Content Type ◽  
Link Type ◽  
Shewanella Algae ◽  
Cyperus Malaccensis

Two Gram-stain-negative, motile, facultatively anaerobic, rod-shaped strains, FJAT-53720T and FJAT-53726, were isolated from rhizosphere sediment of plant Cyperus malaccensis. Phylogenetic analysis based on their 16S rRNA gene sequences revealed that strains FJAT-53720T and FJAT-53726 were affiliated to the genus Shewanella (forming an independent cluster) with the highest sequence similarity to the type strain of Shewanella algae . Optimum growth of both strains was observed at 30 °C and pH 7. The respiratory quinones were Q-7, Q-8 and MK-7. The polar lipid profile included phosphatidylmethyl ethanolamine, phosphatidylethanolamine, diphosphatidylglycerol, one unidentified aminophospholipid and four unknown phospholipids. The major fatty acids of strains FJAT-53720T and FJAT-53726 were iso-C15:0, C17 : 1 ω8c and summed feature 3. The genomic DNA G+C content of strain FJAT-53720T was 55.6 mol%. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between FJAT-53720T and FJAT-53726 were 97.4 and 77.9 %, confirming that they were similar species and hence FJAT-53720T was selected for further analysis. The ANI and dDDH values between FJAT-53720T and other members of the genus Shewanella were below the cut-off level (95–96 %; 70 %) for species delineation. Based on the above results, FJAT-53720T represents a novel species of the genus Shewanella , for which the name Shewanella cyperi sp. nov. is proposed. The type strain is FJAT-53720T (=KCTC 82444T=GDMCC 1.2207T).

scholarly journals Promising Mechanical, Thermal, and Ballistic Properties of Novel Epoxy Composites Reinforced with Cyperus malaccensis Sedge Fiber

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1776 ◽  
Author(s):  
Lucas de Mendonça Neuba ◽  
Raí Felipe Pereira Junio ◽  
Matheus Pereira Ribeiro ◽  
Andressa Teixeira Souza ◽  
Eduardo de Sousa Lima ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Fiber Composite ◽  
Control Sample ◽  
Epoxy Composites ◽  
Neat Epoxy ◽  
Degradation Temperature ◽  
Cyperus Malaccensis ◽  
Ballistic Properties ◽  
Natural Composites ◽  
Izod Impact

Composites reinforced with natural lignocellulosic fibers (NLFs) are gaining relevance as the worldwide demand for renewable and sustainable materials increases. To develop novel natural composites with satisfactory properties, less common NLFs should also be investigated. Among these, the Cyperus malaccensis (CM), a type of sedge fiber, is already used in simple items like ropes, furniture, and paper, but has not yet been investigated as composite reinforcement for possible engineering applications. Therefore, the present work evaluated for the first time the properties of novel epoxy composites incorporated with 10, 20, and 30 vol.% of CM sedge fibers. Tensile, Izod-impact, and ballistic impact tests were performed, as well as Fourier transform infrared (FT-IR) spectroscopy and thermal analysis of the composites. Results disclosed a decrease (−55%) in tensile strengths as compared to the neat epoxy. However, the elastic modulus of the 30 vol.% sedge fiber composite increased (+127%). The total strain and absorbed ballistic energy did not show significant variation. The Izod impact energy of the 30 vol.% composite was found to be 181% higher than the values obtained for the neat epoxy as a control sample. An increase in both stiffness and toughness characterized a reinforcement effect of the sedge fiber. The thermal analysis revealed a slight decrease (−15%) in the degradation temperature of the CM sedge fiber composites compared to the neat epoxy. The glass-transition temperatures were determined to be in the range of 67 to 81 °C.

Abundance and composition of denitrifiers in response toSpartina alterniflorainvasion in estuarine sediment

2013 ◽  
Vol 59 (12) ◽  
pp. 825-836 ◽  
Author(s):  
Qiufang Zhang ◽  
Jingjing Peng ◽  
Qian Chen ◽  
Xiaoru Yang ◽  
Youwei Hong ◽  
...  
Keyword(s):  
River Estuary ◽  
Species Interaction ◽  
Nitrite Reduction ◽  
Native Plant ◽  
Jiulong River Estuary ◽  
Cyperus Malaccensis ◽  
Population Sizes ◽  
Invaded Zone ◽  
Vegetation Species ◽  
Flat Zone

Nitrite reduction is regulated by nitrite reductase encoded by nirK and nirS genes. This study aimed to investigate the abundance and composition of nirK- and nirS-containing denitrifiers in response to Spartina alterniflora invasion at the Jiulong River estuary, China. The sediment samples (depth: 0–5.0 and 5.1–20 cm) were collected from 3 vegetation zones, 1 dominated by the exotic plant S. alterniflora, 1 dominated by the native plant Kandelia candel, and 1 dominated by the native plant Cyperus malaccensis, and from an unvegetated flat zone. nirK- and nirS-containing denitrifier population sizes were lower in the invaded and nonvegetated zones than in those dominated by native K. candel and C. malaccensis, which were impacted by depth – vegetation species interaction. The ratios of nirS to nirK abundance ranged from 42.10 to 677.27, with the lowest ratio found for the upper layer in the invaded zone. The nirK-containing denitrifier compositions showed a 35% similarity between invaded zone and others. Most of the sequences of nirK genes recovered from the S. alterniflora zone were specific and distinct from those of nirK genes recovered from other vegetation types; nirS genes in the invaded zone were highly divergent. These results reveal that S. alterniflora invasion has a significant effect on the abundance and composition of both nirK- and nirS-containing denitrifiers, and nirS-containing denitrifiers were less responsive to invasion than nirK-containing denitrifiers.

scholarly journals Differences in biomass and silica content in typical plant communities with ecotones in the Min River estuary of southeast China

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7218
Author(s):  
Hui Gao ◽  
Shuijing Zhai ◽  
Zhigao Sun ◽  
Juan Liu ◽  
Chuan Tong
Keyword(s):  
Plant Competition ◽  
River Estuary ◽  
Aquatic Organisms ◽  
Silica Content ◽  
Plant Management ◽  
Min River ◽  
Cyperus Malaccensis ◽  
Min River Estuary ◽  
Si Content ◽  
Estuarine Coastal

Silica (Si) is a basic nutrient requirement for many aquatic organisms and its biogeochemical cycle plays an important role in estuarine coastal ecosystems. However, little is known about the role Si plays during plant–plant interactive processes in the marsh ecosystems. Here, variations in biomass, biogenic silica (BSi) content, and available Si content of Cyperus malaccensis-dominated marshes, Phragmites australis-dominated marshes, and their ecotonal marshes were studied in the Shanyutan marsh in the Min River estuary, China. Results showed that C. malaccensis and P. australis biomass in ecotones was lower than those in typical communities by 46.4% and 46.3%, respectively. BSi content in aboveground organs of C. malaccensis and culms and roots of P. australis was lower in ecotones than in typical communities, whereas BSi content in other organs showed the opposite trend. Biomass allocation in C. malaccensis and P. australis roots in ecotones was higher by 56.9% and 19.5%, respectively, and BSi stock in C. malaccensis and P. australis roots was higher than that in typical communities by 120.9% and 18.9%, respectively. Available Si content in ecotonal marsh soils was 12.6% greater than that in typical communities. Thus, the two plant species may use different strategies for Si accumulation and allocation in ecotones to adapt to the competitive environment. P. australis may expand primarily via occupation of wider aboveground space, thereby increasing the Si accumulation capacity in aboveground organs. Meanwhile, C. malaccensis may increase the Si allocation capacity of its roots to withstand the pressure from P. australis. This study will provide new insights into marsh plant competition from the perspective of Si, which can also benefit plant management in marsh ecosystems.

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