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Persistent Organochlorine Compounds Levels in Selected Fish Species from Lake Victoria and Associated Human Health Risks
Alex Wenaty,
Arvid Fromberg,
Faith Mabiki,
Bernard Chove,
Anders Dalsgaard,
Robinson Mdegela
Issue:
Volume 8, Issue 1, February 2019
Pages:
1-9
Received:
17 December 2018
Accepted:
14 January 2019
Published:
31 January 2019
Abstract: Nile perch (L. niloticus ) and Nile tilapia (O. niloticus) are the major commercial fish species in Lake Victoria region of Tanzania. This study was conducted to assess the levels of persistent organochlorine compounds, namely PCBs and OCPs in these two fish species and the probable human health risks associated with the consumption of these two fish species from Lake Victoria. Fish samples were collected between May and August 2016 and the necessary anthropometric measurements such as length and weight were taken. The extraction was done using a modified QuEChERS method and the identification and quantification of the chemicals were done using GC/ECDs. The results of this study revealed that fish species sampled were undersize, which was an indication of overfishing and abuse of bylaws. Among the 19 OCPs which were considered, only four (β- HCH, HCB, Aldrin and Dieldrin) were detected at measurable quantities. β- HCH ranged from <0.24 to 1.19µg/kg. The mean concentrations were 0.77±0.43µg/kg and 0.56±0.16µg/kg for L. niloticus and O. niloticus respectively. HCB levels ranged from <0.18 to 0.59µg/kg in L. niloticus and <0.18µg/kg in O. niloticus. Aldrin ranged from <0.14 to 0.34µg/kg in L. niloticus whereas it was not detected in O. niloticus. Moreover, Dieldrin residues ranged from <0.17 to 1.06µg/kg in O. niloticus but were not detected in L. niloticus. Generally, there were slightly higher levels of the detected OCPs in L. niloticus than the corresponding levels in O. niloticus mainly due to their differences in trophic levels and feeding habits. The indicator PCBs were not detected in all the investigated fish samples. The levels of all the detected organochlorines were far below the MRL set for fish and fishery products suggesting that the fresh fish from Lake Victoria are safe for human consumption. Low levels of the detected residues and non- detection of many organochlorines considered indicate that contamination in Lake Victoria has not reached alarming levels. The human health risk assessment of the detected organochlorines showed cancer risk from 8.6E-06 to 3.2E-05 for children and from 7.8E-06 to 1.3E-05 for adults indicating that there is a low cancer risk for both age groups. The non- cancer risks (HI) on the other hand, were 5.7E-02 for children and 4.7E-02 for adults, which is an indication of an insignificant risk.
Abstract: Nile perch (L. niloticus ) and Nile tilapia (O. niloticus) are the major commercial fish species in Lake Victoria region of Tanzania. This study was conducted to assess the levels of persistent organochlorine compounds, namely PCBs and OCPs in these two fish species and the probable human health risks associated with the consumption of these two fi...
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Chromosome Karyotype Analysis and Evolutionary Trend of Half-Sib Families of Ancient Ginkgo Biloba L
Sun Limin,
Dong Yao,
Sun Xia,
Xing Shiyan,
Zhang Yiqun,
Zhao Jinhong
Issue:
Volume 8, Issue 1, February 2019
Pages:
10-17
Received:
9 January 2019
Accepted:
16 February 2019
Published:
6 March 2019
Abstract: The karyotype of 28 families from Shandong, Zhejiang, Guizhou and other 12 provinces exist in half-sib families of ancient Ginkgo biloba gemplasm repository was studied by squashing method with young leaves from these families. Results: The results showed that the number of chromosomes in 28 families was 2n=2x=24. The medium-short chromosomes and the medium-long chromosomes were dominant. The karyotype consists of three types: median region chromosome (m), submedian region chromosome (sm) and subterminal region chromosome (st). 71# family is the most primitive, while the 40# family is the most evolved. Families from southwestern China have a low degree of evolution, while those from eastern and southern China have a high degree of evolution.
Abstract: The karyotype of 28 families from Shandong, Zhejiang, Guizhou and other 12 provinces exist in half-sib families of ancient Ginkgo biloba gemplasm repository was studied by squashing method with young leaves from these families. Results: The results showed that the number of chromosomes in 28 families was 2n=2x=24. The medium-short chromosomes and t...
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Seeking Inevitable from the Accident——Discussion on the Methodology of Sublimating Agricultural Science and Technology
Sun Huilan,
Yan Zhongbing
Issue:
Volume 8, Issue 1, February 2019
Pages:
18-22
Received:
19 November 2018
Accepted:
20 February 2019
Published:
12 March 2019
Abstract: Many agricultural technology theory and results is derived from “accidental discovery” of production practice, to explore the general laws of this kind of accident occurred, and found it contains inevitability. Searching actively for accidents in agricultural production and technology promotion and conducting meticulous in-depth and unremitting research can sublimate the theory of agricultural science and technology and have important guiding significance for production practice.
Abstract: Many agricultural technology theory and results is derived from “accidental discovery” of production practice, to explore the general laws of this kind of accident occurred, and found it contains inevitability. Searching actively for accidents in agricultural production and technology promotion and conducting meticulous in-depth and unremitting res...
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Response of Bread Wheat (Triticum Aestivium L.) Yield and Yield Components to Different Level of Phosphorous in Gozamen District, East Gojjam
Issue:
Volume 8, Issue 1, February 2019
Pages:
23-26
Received:
1 February 2019
Accepted:
12 March 2019
Published:
29 March 2019
Abstract: The field experiment was done during the cropping season of 2017 at Gozamin district, North western Ethiopia to see the influence of different rates phosphorous fertilizer on the yield and yield components of Bread wheat. The experiment was laid out by Randomized Complete Block Design (RCBD) design with three replications of six phosphorous rates (0, 23, 46, 69, 92 and 115 kg ha-1). Significant differences in plant height (cm), number of effective tillers per plant, number of kernels per spike, spike length (cm), grain yield (Q ha-1) and biological yield (Q ha-1) were observed by the application of different rates of phosphorus fertilizers. However, only Harvesting index (Q ha-1) was not significantly affected by different rates of phosphorus fertilizers. It is concluded that phosphorus application at the rate of 115 kg ha-1 is more conducive to achieve the maximum yield (94.47 Q ha-1) for the research area as compared to the other treatments.
Abstract: The field experiment was done during the cropping season of 2017 at Gozamin district, North western Ethiopia to see the influence of different rates phosphorous fertilizer on the yield and yield components of Bread wheat. The experiment was laid out by Randomized Complete Block Design (RCBD) design with three replications of six phosphorous rates (...
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Weed Science Education at the Tertiary Educational Level in Nigeria
Udensi Udensi Ekea,
Godwin-Egein Monday Ilegimokuma,
Omovbude Sunday
Issue:
Volume 8, Issue 1, February 2019
Pages:
27-30
Received:
28 February 2019
Accepted:
9 April 2019
Published:
29 April 2019
Abstract: Weed Science is a discipline in that it deals with the study of vegetation management in agriculture, horticulture, aquatics, right-of-way, estates or amenities, essentially anywhere plants need to be managed. It involves the study of all the tools available for this purpose. In comparison with other plant protection disciplines, it has not enjoyed being a distinct discipline. Its study has in most cases been aligned with degrees in Agriculture and Agricultural related discipline. It has always been a component of degrees in Agricultural Science or Crop Science in Nigerian universities. This paper reviews the current status of Weed Science education in Nigeria. In Nigerian universities courses on weed control is part of degree programmes in Agriculture, Horticulture and/or Biological/Plant Sciences, where only aspects of weed characteristics and their control with herbicides, are taught in the third or final years. At the Masters or graduate levels it is taught where there is a Resident Weed Scientist. Because of government’s insensitivity the growth and development of professionalism is stifled. To date, of 149 universities in the country, only 58 of them offer one form of a course or the other that is related to weed science, constituting 44.8%. There were no Weed Scientists present in all the categories of Polytechnics, hence limiting per capita availability of Weed Scientists in the country. This situation does not engender participation or entrant of new members into the discipline. Inadequate funding of the education and agricultural sectors has been the bane of developing adequate manpower and expertise needed in the area. For instance the Weed Science Society of Nigeria has been in existence since 1971, but their presence has not adequately influenced professionalism due to lack of appropriate policy environment. Weed Science education in Nigeria has not found its rightful space in the national polity. If national agricultural development is to remain afloat, Weed Science education should be properly appropriated through adequate budgetary allocation to the Agriculture and Education sectors. This will enhance the quality of teaching and recruitment of Weed Scientist.
Abstract: Weed Science is a discipline in that it deals with the study of vegetation management in agriculture, horticulture, aquatics, right-of-way, estates or amenities, essentially anywhere plants need to be managed. It involves the study of all the tools available for this purpose. In comparison with other plant protection disciplines, it has not enjoyed...
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