Competitive ability of some cover crop species against Asystasia gangetica and Pennisetum polystachion     

Batoul Samedani  Abdul Shukor Juraimi  Md. Parvez Anwar  Mohd Yusop Rafii  Sheikh Abdullah Sheikh Awadz  Abudul Rahim Anuar 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(7):571-582

Abstract

Asystasia gangetica and Pennisetum polystachion are the most troublesome weeds in oil palm plantations in Malaysia and establishment of cover crops under oil palms is an integral part of sustainable weed management in plantations. Replacement-series experiments were conducted to evaluate the mode and strength of competitiveness of four legume cover crop species, Calopogonium caeruleum, Centrosema pubescens, Mucuna bracteata and Pueraria javanica, and one soft grass species, Axonopus compressus, against Asystasia gangetica and Pennisetum polystachion. Relative yield, relative yield total and relative crowding coefficient were calculated with reference to shoot biomass. Asystasia gangetica was a consistently weaker competitor than Pennisetum polystachion. The legume cover crop species had higher relative yield when grown in mixtures, whereas the yield of Asystasia gangetica was lower in mixtures with legumes than in monoculture. The higher competitiveness of legumes was due to greater canopy height and leaf area index. Centrosema pubescens was a slightly weaker competitor than the other legumes. Although leaf area per plant of Centrosema pubescens did not differ from that of other three legumes, canopy height and blocking photosynthetically active radiation to the soil surface were lower. When grown with a cover crop for 12 weeks, dry weight per plant, leaf area and shoot number of Pennisetum polystachion increased as its proportion decreased in mixtures. Relative yield data indicated that Pennisetum polystachion is a strong competitor. Axonopus compressus was less susceptible to Pennisetum polystachion interference than the legumes. All cover crop species studied proved highly competitive against Asystasia gangetica, but none could compete against Pennisetum polystachion. The study confirms the feasibility of using a cover crop for management of Asystasia gangetica.  相似文献   

Soil morphological and chemical properties in homegardens on sandy beach ridges along the east coast of Peninsular Malaysia     

Khairul Hafiz Mohd Yusoff  Arifin Abdu  Katsutoshi Sakurai  Sota Tanaka  Yumei Kang 《Soil Science and Plant Nutrition》2013,59(4):357-368

The morphological and chemical properties of homegardens in the beach ridges with interspersed swales (BRIS) soils were evaluated in order to find a clue for developing sustainable agricultural management. Field survey and soil sampling were conducted at the homegardens and secondary forests in Sungai Ular Village and in the experimental farm of Malaysian Agriculture Research Institute (MARDI), Cherating Station. Chemical fertilizers including ash, charcoal waste and plant litter were applied to the homegardens in both the inland-ward area (HG-I) and in the shoreline area (HG-S). Manure was applied in HG-I and seafood waste from fish processing was buried in the soils in HG-S. High correlation was found between total carbon (T-C) and cation exchange capacity (CEC), indicating soil organic matter was the determinant factor for CEC in the very sandy BRIS soils. The levels of T-C, total nitrogen (T-N), and CEC at 0–10 cm in HG-I in parallel with increasing ages of homegardens. The soils in 0–10 cm and 20–30 cm showed higher levels of T-C and T-N with higher C/N ratios in HG-I than in HG-S and the MARDI farm. The high levels of exchangeable Ca, Mg, and K in HG-I compared with the MARDI farm, suggesting that improved CEC with increasing soil organic matter in HG-I heighten the retention of basic cations supplied as chemical fertilizer, ash, and manure. The level of available P was higher in HG-S than HG-I, attributed by the seafood waste application in the shoreline area. Thus, on the BRIS, the levels of soil organic matter and nutrients can be sustained by the homegarden management although it cannot be regarded as a closed system compared with those in the other tropical regions because chemical fertilizer was used and a certain amounts of nutrients seemed to leach down beyond plant rooting depth.  相似文献   

Changes of Physical and Chemical Characteristics during Microbial Composting of Rice Straw at Various pH Levels     

H. Kausar  Halimi Mohd Saud  Sheikh Hasna Habib  Radziah Othman  M. S. H. Bhuiyan 《Compost science & utilization》2013,21(3):153-163

ABSTRACT

The physical and chemical parameters were monitored for seven weeks during Trichoderma/Aspergillus inoculated rice straw composting at various pH levels. Three treatments (A, B, and C) were inoculated with lignocellulolytic microbial consortium (Aspergillus niger, F44 and Trichoderma viride, F26) and three were un-inoculated (D, E, and F). pH of the starting materials was amended to 5.75 (A and D), 6.75 (B and E), and 7.75 (C and F) with either acetic acid or sodium hydroxide. Three typical phases of temperature were observed both in inoculated and un-inoculated treatments during composting: mesophilic phase, thermophilic phase, and followed by cooling and maturation phase. The bioconversion were maximum in Trichoderma/Aspergillus inoculated treatments within 14–21 days as indicated by the profiles of electrical conductivity, bulk density, total carbon and nitrogen, and germination index. After day 21, the germination index of Trichoderma/Aspergillus inoculated treatment (B) without any pH amendment was increased to 74.5 indicating the maturity of compost and suitability for field application.  相似文献   

Qualitative and quantitative evaluation of avian demineralized bone matrix in heterotopic beds     

M. Reza Sanaei DVM  MVSc  Jalila Abu DVM  MS  PhD  Mojgan Nazari DVM  MVSc  Mohd Zuki A.B. DVM  PhD  Zeenathul N. Allaudin DVM  MS  PhD 《Veterinary surgery : VS》2013,42(8):963-970

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Carbon Dioxide Capture with Amine-Grafted Activated Carbon     

Houshmand  Amirhossein  Daud  Wan Mohd Ashri Wan  Lee  Min-Gyu  Shafeeyan  Mohammad Saleh 《Water, air, and soil pollution》2012,223(2):827-835

There are several possible methods by which amine groups can be grafted on the surface of activated carbon (AC) to improve their capacity for CO₂ adsorption. Ethylenediamine and diethylenetriamine were selected as amino compounds for anchoring on the surface of an oxidized AC. Oxidation of AC was carried out by concentrated nitric acid. For each amino compound, two “in-solvent” and “solvent-free” methods with a number of grafting times were studied. Nitrogen adsorption–desorption at 77 K and proximate and ultimate analysis were used to determine physical and chemical characteristics of the samples. Temperature-programmed (TP) CO₂ adsorption test from 30°C to 120°C were performed to investigate the effect of modification on CO₂ capture. The modification clearly had a negative effect on the textural characteristics of the samples, so the samples showed a less CO₂ uptake at lower temperatures. However, the decrease of capture capacity with increasing temperature is to somewhat softer for amine-grafted samples, so that they have a capacity comparable to the parent sample or even more than that at elevated temperatures. This property may give the new adsorbents this opportunity to be used at flue gas temperature with a higher efficiency. CO₂ capture capacity per unit surface area of all the amine-modified samples, however, was significantly improved, compared to the parent sample presenting a great influence of amino groups on the CO₂ capture capacity. Moreover, the used amine compounds and grafting methods were compared in terms of adsorbent characteristics and CO₂ uptake curves. Cyclic adsorption–desorption tests showed a satisfactory regeneration for the modified samples.  相似文献   

Optimal set of microsatellite markers required to detect illegitimate progenies in selected oil palm (Elaeis guineensis Jacq.) breeding crosses     

Siti Hazirah Zolkafli  Maizura Ithnin  Kuang-Lim Chan  Mohd Isa Zainol Abidin  Ismanizan Ismail  Ngoot Chin Ting  Leslie Cheng-Li Ooi  Rajinder Singh 《Breeding Science》2021,71(2):253

Oil palm is continually being improved via controlled crossing of selected palms to ensure sustainable yields and productivity. As such, correct parental assignment is important as the presence of illegitimates will compromise the progress of improvement. In the present study, we determined the optimal number of microsatellite (SSR) markers for detection of illegitimates in selected oil palm crosses with high confidence. Determining the optimal number of markers to assign parentage will ensure that the DNA fingerprinting will be cost effective for routine use as a quality control tool in oil palm improvement programs. Here, we evaluated a wide range of crosses that included a cross derived from wild germplasm palm. The results revealed that markers with high PIC are informative and detect most of the alleles present in a cross, including those exhibited by the illegitimates. A larger number of optimum sets of markers are needed to detect all illegitimates for crosses with higher levels of genetic diversity. The optimal number of polymorphic SSR markers determined in the present study can ensure that appropriate quality control is implemented for oil palm improvement programs.  相似文献   

SOURCES OF PRODUCTIVITY GROWTH IN RAINBOW TROUT AQUACULTURE IN IRAN: TECHNICAL EFFICIENCY CHANGE OR TECHNOLOGICAL PROGRESS?     

Behrooz Hassanpour  Mohd Mansor Ismail  Zainalabidin Mohamed  Nitty Hirawaty Kamarulzaman 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):218-234

This study investigates the sources of total factor productivity (TFP) growth in rainbow trout production in Iran using data envelopment analysis (DEA). The Malmquist index is then employed to decompose the TFP growth into technical efficiency change and technological progress. We utilized panel data of 207 trout farms in the country over a 5-year period from 2003 to 2007. The results of this study revealed that TFP growth of rainbow trout farming has an increasing trend over the period at an average annual rate of 3.7%. The trend of cumulative technological change is negative and tends to be contrary to cumulative technical efficiency change. Although there is no technological change or innovation on trout farming, the technical efficiency change was found to be the sole source for TFP change, whereas the mean of technical efficiency was estimated to be about 66%. Therefore, there is still a great relative potential for increasing trout production through improvement in managerial efficiency as well as technological progress. The study suggests that Iran also has considerable room to enhance trout aquaculture's TFP growth by shifting the production frontier with adoption of new technologies and improving innovation.  相似文献   

Molecular characterization,tissue distribution of Follicle‐Stimulating Hormone (FSH) beta subunit and effect of kisspeptin‐10 on reproductive hormonal profile of Catla catla (Hamilton, 1822)          下载免费PDF全文

Mohd Ashraf Rather  Irfan Ahmad Bhat  Niti Sharma  Rupam Sharma  Gireesh‐Babu P  Aparna Chaudhari  Jeetendra Kumar Sundaray 《Aquaculture Research》2016,47(7):2089-2100

Gonadotropin (GTH) hormones are glycoprotein which stimulates gonadal maturation in vertebrates. Follicle stimulating hormone is involved in initiation of gametogenesis and regulation of gonadal growth. FSHβ has been cloned and characterized from the brain of Catla catla. The FSHβ full‐length of cDNA sequence of 523 bp comprised 3, 394 and 128 bp of 5′‐UTR, open reading frame (ORF) 3′‐UTR respectively. The coding region of C. catla FSHβ encoded a peptide of 130 amino acids. Phylogenetic analysis of C. catla FSHβ deduced amino acid sequence showed high similarity with Gobiocypris rarus followed by goldfish, Carassius auratus. The qPCR result shows that FSHβ mRNA is mainly expressed in pituitary while moderate and low expression was observed in testis and ovary respectively. Chitosan‐nanoconjugated kisspeptin‐10 (CK‐10) of particle size 125 nm, polydispersity index of 0.335 to 0.65 and zeta potential of ?34.95 mV were synthesized and evaluated at against naked kisspeptin‐10 for their reproductive hormonal profile. Treatment of fish with CK‐10 showed controlled and sustained surge of the reproductive hormones (FSH & LH) with peak at 12 h. The hormone levels of naked kisspeptin‐10 treated fish decline after 6 h. The sustained release of this CK‐10 will help in reducing maturation age, synchronization of ovulation and spawning in fish. This is the first report on use of chitosan‐nanoconjugated kisspeptin‐10 (CK‐10) for reproduction in fish.  相似文献   

Preliminary observations on effect of nano‐conjugated pheromones on Clarias batrachus (Linnaeus, 1758)     

Rupam Sharma  Mohd Ashraf Rather  Ramya Vijaykumar Leela  Himadri Saha  Suresh Babu Padinhate Purayil  Shabir Ahmad Dar  Sukham Munilkumar 《Aquaculture Research》2014,45(8):1415-1420

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The induction of Hsp70 synthesis by non‐lethal heat shock confers thermotolerance and resistance to lethal ammonia stress in the common carp,Cyprinus carpio (Linn)     

Yeong Yik Sung  Hon Jung Liew  Abol Munafi Ambok Bolong  Mohd. Effendy Abdul Wahid  Thomas H MacRae 《Aquaculture Research》2014,45(10):1706-1712

Exposure to heat‐shock protein (Hsp) stimulating factors induces Hsp accumulation and confers tolerance to lethal ammonia stress on the common carp Cyprinus carpio. This study investigated whether a non‐lethal heat shock bestowed similar protective effects against ammonia and induced thermotolerance, both thought to be rendered by increased amounts of Hsps. The 30‐min lethal temperature (30 min LHT) and 1‐h lethal ammonia concentration (1 h LCT) for this species occurred at 41°C and 14.2 mg/L NH₃ respectively. Heating juvenile carp (5 cm) from 28°C to 32, 34 and 38°C, with a subsequent 8‐h recovery period augmented tolerance to lethal heat and ammonia perturbation by two to threefold as compared with animals held at 28°C. Protection occurred in conjunction with Hsp70 accumulation in gills, substantiating the role of this Hsp in enhancing the stress tolerance of common carp.  相似文献