Comparison of growth,survivorship, seed production and shedding of eight weed species in a wheat crop in Western Australia     

Catherine P. D. Borger  Abul Hashem  Gurjeet S. Gill 《Weed Research》2020,60(6):415-424

Development of integrated weed management strategies is dependent on a thorough knowledge of the demography of individual species. The current research established eight winter or summer weed species in a winter annual wheat cropping system at Wongan Hills, Western Australia, and investigated emergence of the first cohort of each species, survivorship, plant size, seed production and seed shedding over three years (2016–2019). The winter weeds Bromus diandrus and Lolium rigidum emerged at the same time as the wheat crop, and the initial cohort of marked plants had 100% survival to seed production in each year. By comparison, other winter weed species like Hordeum leporinum, Rumex hypogaeus, Sonchus oleraceus and Polygonum aviculare frequently emerged later than the crop and had a lower percentage of plants surviving to seed production. However, individual S. oleraceus and P. aviculare plants had the greatest seed production compared to other species. All winter weeds had variable patterns of seed shedding between years, with the exception of L. rigidum. Summer weed species emerged at the same time, but plants in the initial cohort of each species did not always survive to produce seed. The early emergence and high survivorship of B. diandrus indicates high competitive ability, but shedding commenced at a similar time to L. rigidum and harvest weed seed control may be a viable control method for this species.  相似文献   

Heavy Metal Contamination of Soil and Vegetation in the Vicinity of Industries in Bangladesh     

Kashem  MD. Abul  Singh  Bal Ram 《Water, air, and soil pollution》1999,115(1-4):347-361

Water, Air, &; Soil Pollution - A study was conducted to investigate the heavy metal contamination of soil and vegetation in the vicinity of industries around Dhaka city in Bangladesh....  相似文献   

Detection of a chitinase-like protein in the roots of Douglas-fir trees infected with Armillaria ostoyae and Phellinus weirii     

Robinson RM  Sturrock RN  Davidson JJ  Ekramoddoullah AK  Morrison DJ 《Tree physiology》2000,20(8):493-502

Protein was extracted from root bark of 11- and 25-year-old interior Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees that were naturally infected with Armillaria ostoyae (Romagnesi) Herink. The proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Root bark tissue adjacent to infected areas had a significantly higher protein concentration than healthy tissue (P < 0.05), whereas the protein concentration of infected tissue was consistently lower (P < 0.05) than that of healthy tissue. The SDS-PAGE profiles of healthy, infected, and adjacent-to-infected root bark tissues revealed significant differences in concentrations of a 29.3-kDa protein. The N-terminal amino acid sequence of the 29.3-kDa protein displayed significant homology (P = 0.013) to a basic endochitinase. Use of a polyclonal antibody raised against the 29.3-kDa putative endochitinase-like protein (ECP) indicated differences in the quantities of ECP in healthy roots compared with roots infected with A. ostoyae in 11- and 25-year-old interior Douglas-fir trees. The antibody was also used to screen for the presence of the 29.3-kDa protein in roots of 24-year-old coastal Douglas-fir (Pseudotsuga menziesii var. menziesii) trees that were artificially inoculated with and colonized by Phellinus weirii (Murr.) Gilbn. The amount of ECP was elevated in root bark of coastal Douglas-fir in response to P. weirii infection, although in lower quantities relative to those found in the A. ostoyae-interior Douglas-fir pathosystem. The sequence homology of the ECP with a basic chitinase, together with its increased synthesis in response to two fungal pathogens, indicate a possible role for this protein in the defense of Douglas-fir against fungal pathogens.  相似文献   

平欧杂种榛主栽品种需冷量、需热量研究          下载免费PDF全文

马庆华  罗青红  艾吉尔&#;阿不拉  曹运强  崔立志  霍宏亮  王贵禧 《林业科学研究》2016,29(3):354-361

[目的]揭示平欧杂种榛主栽品种的需冷量和需热量,更好地指导生产做好区域化栽培。[方法]本研究以16个平欧杂种榛主栽品种的1年生枝条为试材,以野生平榛1年生枝条为对照,通过水培观察的方法,首次对平欧杂种榛的雌、雄花序和叶芽进行需冷量和需热量研究。[结果]表明:平欧杂种榛不同器官的需冷量由低到高依次为雄花序336 1 176 h、雌花序504 1 344 h、叶芽672 1 512 h;需热量由低到高依次为雄花序687.0 998.5GDH℃、雌花序998.5 3 496.1 GDH℃、叶芽2 546.5 4 180.3 GDH℃;不同品种、器官在刚满足最低蓄冷要求时需热量最高,随着蓄冷时间的延长,需热量逐渐减少。[结论]首次报道了平欧杂种榛主栽品种雄、雌花序和叶芽的需冷量和需热量数据,其中,达维、平欧48号等品种花器官需冷量较低,辽榛2号、平欧545号等品种花器官需冷量较高;玉坠、平欧69号等品种花器官需热量较低,辽榛1号、辽榛4号等品种花器官需热量较高,上述研究丰富了榛属植物开花和休眠解除方面的数据,可为平欧杂种榛的引种和栽培提供参考。  相似文献   

Fecal carriage of multi-drug resistant and extended spectrum β-lactamases producing E. coli in household pigeons,Bangladesh     

Badrul Hasan  Kamrul Islam  Murshidul Ahsan  Zakir Hossain  Mahmudur Rashid  Bibhas Talukder  Kabir Uddin Ahmed  Björn Olsen  Mohammad Abul Kashem 《Veterinary microbiology》2014

Antibiotic resistance and ESBL constitute a risk to human and animal health. Birds residing close to humans could mirror the spectrum of human associated antibiotic resistance. Household pigeons were screened in Bangladesh to shed light on human associated, as well as, environmental antibiotic resistance. Escherichia coli from pigeons (n = 150) were tested against 11 antibiotics. 89% E. coli isolates were resistant to one or more critically important human antibiotics like ampicillin, cefadroxil, mecillinam, ciprofloxacin, gentamicin and tigecycline. No carbapenamase-producers were detected and the lower ESBL prevalence (5%) in pigeons. ESBL-producing E. coli isolates had bla_CTX-M-15 genes. Pigeons shared some bacterial clones and had bird associated sequence types like E. coli ST1408. Fecal carriage of bacteria resistance of critically important human antibiotics, together with examples of shared genotypes among pigeons, indicate the human-birds and bird to bird transmissions are important in the epidemiology of antibiotic resistance.  相似文献   

Mapping QTLs associated with root traits using two different populations in wheat (Triticum aestivum L.)     

Muhammad Rezaul Kabir  Gang Liu  Panfeng Guan  Fei Wang  Abul Awlad Khan  Zhongfu Ni  Yingyin Yao  Zhaorong Hu  Mingming Xin  Huiru Peng  Qixin Sun 《Euphytica》2015,206(1):175-190

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Alleviation of cadmium phytotoxicity by magnesium in Japanese mustard spinach   总被引：3，自引：0，他引：3  

MD. Abul KASHEM  Shigenao KAWAI 《Soil Science and Plant Nutrition》2007,53(3):246-251

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Optimization of Compatible Mixed Cultures for Liquid State Bioconversion of Municipal Wastewater Sludge     

Alam  Md. Zahangir  Fakhru'l-Razi  A.  Abd-Aziz  Suraini  Molla  Abul H. 《Water, air, and soil pollution》2003,149(1-4):113-126

The filamentous fungal strains such as Penicillium corylophilum (P), Aspergillus niger (A), Trichoderma harzianum (T) and Phanerochaete chrysosporium (PC) isolated from its relevant sources (wastewater, sewage sludge and sludge cake) were selected for compatible/incompatible mixed cultures. Six combinations of P. corylophilum and A. niger (P/A); P. corylophilum and P. chrysosporium (P/PC); P. corylophilum and T. harzianum (P/T); A. niger and T. harzianum (A/T); A. niger and P. chrysosporium (A/PC); T. harzianum and P. chrysosporium (T/PC) were used to evaluate their potential performance as compatible/incompatible mixed culture for the treatment of municipal wastewater sludge in a bioconversion process. The results of the present study showed that the combinations of P/A, P/PC and A/PC showed compatible growth and the rest of the combinations (P/T, A/T and T/PC) were incompatible cultures. A maximum production of dry biomass and dry filter cake were recorded in the compatible mixed culture of P. corylophilum and A. niger (P/A). A maximum reduction of COD (90%) and a decreased filtration time of treated sludge was observed in the case of P/A microbial mixed culture. The pH value was also affected by the fungal cultures. Effective results were observed by using microbial mixed culture after four days of treatment compared to other treatments (2 and 6 days).  相似文献   

Gene Cloning and Tissue Expression Analysis of a PR-5 Thaumatin-Like Protein in Phellinus weirii-Infected Douglas-Fir     

Zamani A  Sturrock RN  Ekramoddoullah AK  Liu JJ  Yu X 《Phytopathology》2004,94(11):1235-1243

ABSTRACT In western North America, Douglas-fir (Pseudotsuga menziesii) is the most economically important conifer species susceptible to laminated root rot caused by Phellinus weirii. While attempting to internally sequence an endochitinase found to be up-regulated in P. weirii-infected Douglas-fir roots, we obtained overlapping peptide fragments showing 28% similarity with a PR-5 thaumatin-like protein (TLP) designated PmTLP (Pm for Pseudotsuga menziesi). A rabbit polyclonal antibody was reared against a synthetic peptide composed of a 29-amino-acid-long, conserved, internal sequence of PmTLP and purified by immunoaffinity. Western immunoblot analysis of infected roots of 24-year-old coastalfir showed significantly higher amounts of PmTLP (P < 0.01) closest to the point of P. weirii inoculation and infection than in uninfected regions of the same root. The antibody was also used to screen for PmTLP in roots of 25-year-old interior Douglas-firs naturally infected with a related pathogen, Armillaria ostoyae, and results showed significantly higher levels of PmTLP in bark tissues adjacent to infection (P < 0.05) than in uninfected tissue. Using polymerase chain reaction (PCR)-based cloning, the cDNA of PmTLP was shown to have a 702-bp open reading frame with a signal peptide cleavage site at 155 bp corresponding to a 29-amino-acid-long residue prior to the start of the N-terminal. Based on the deduced amino acid sequence, the molecular mass of the putative PmTLP was calculated to be 21.0 kDa with an isoelectric point of 3.71. Alignment analysis of PmTLP cDNA with a representative genomic DNA PCR sequence showed presence of one intron of variable size, within the coding region. The induction of PmTLP at the site of root infection and its presence in needle tissue suggests a general role for this protein in adaptation to stress and may be part of an integrated defense response initiated by the host to impede further pathogen spread.  相似文献   

Soil amendment with city sewage sludge increases soil extractable cadmium,nickel and zinc more than tannery,pharmaceutical and paper mill wastes     

Abul Kashem  Bal Ram Singh 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(2):134-139

Abstract

The distribution of DTPA-extractable Cd, Ni and Zn in four profile samples collected from areas contaminated with wastes from tannery, city sewage, pharmaceutical and paper mills located at different places in Bangladesh was investigated. Soil samples were analysed for the total and their DTPA-extractable metal contents. The total concentration of metals in the soil horizons ranged from 0.07 to 0.62 mg kg^?1 for Cd, 31 to 54 mg kg^?1 for Ni and 59 to 838 mg kg^?1 for Zn, respectively. These metal concentrations were highest in the surface and lowest in the subsurface horizons. This trend was also observed for the DTPA-extractable amounts of these metals. The relative extractability, expressed as the ratio of DTPA to total contents (aqua regia-extractable) was 33 to 46% for Cd, 2 to 10% for Ni and 3 to 28% for Zn, respectively, in the A1 horizon, while in the B and C horizons the ratios decreased gradually as did total concentration, indicating that metal contamination was primarily limited to the surface horizon. For all three metals, the above mentioned ratio was highest in the city sewage soil and the lowest in the paper mill soil. In general, the extent of contamination among the profiles investigated was in the following order: city sewage>tannery>pharmaceutical>paper mill soil. Higher ratios of DTPA-extractable Cd, Ni and Zn in the city sewage soil than the other soils may create a risk for the contamination of agricultural products and ground water.  相似文献