Determination of some dominant genetic characteristics and morpho-meristic features for selection of rainbow trout (Oncorhynchus mykiss) broodstocks

In this study, Iranian and French male and female Oncorhynchus mykiss broodstocks were divided into two groups 50 and 24 respectively in Research center of genetic and breeding of coldwater fishes, Yasouj, Iran and the genetic structure of them was investigated using 6 microsatellite markers. Then 19 morphometric and 5 meristic of broodstock were measured and compared in two populations. Along with broodstock maturation, fertilization 1:1(female:male) were randomly assigned and occurred in 25 of 12 Iranian and French treatment respectively. Reproductive parameters were recorded for the whole family. Average number of observed alleles in Iranian and French stocks was 6.68 and 6.83, respectively. Average number of effective alleles in Iranian and French stocks was 3.13 and 3.45 respectively. Fixation index Fst was calculated based on allelic frequency between two stocks was 0.058 with significant difference between 2 stocks. Morphometric analysis showed significant difference between two stocks in 8 characteristics. Meristic characters was without significant difference in broodstock groups. Eyed percentage for french broodstock calculated zero and deleted. Fertilization rate (100-0), the eyed percentage (98- 0), The hatch rate (98-0), the average fecundity 4114.708, the average eggs size 4.88 mm, Survival in the first three months 19-73% calculated for Iranian broodstocks. Considering the quality of eggs and larvae at different stages and selection between the different family and the within family remained 10 treatments and are kept as future broodstocks. The relationship between fecundity - egg size, fecundity - weight , fecundity - length, egg size- weight was performed using regression. The results showed that Fecundity was influenced more by weight and productive length. The research is beginning to ID the broodstock in our country.

Women in fisheries in Africa

The diverse and productive fisheries in Africa’s coastal countries depend greatly on the contributions of women, who are today increasingly asserting their right to livelihood and support. The 30,490 km of coastline around the African continent is home to many small-scale traditional fishing communities who depend on these shores for their livelihoods. In addition, the continent hosts vast lakes which provide critical sources of food and livelihoods for many inland communities.

The feasibility of milkfish (Chanos chanos) aquaculture in Solomon Islands

Fish is crucial to food and nutrition security in Solomon Islands, and demand is expected to increase due to a growing population. However, it is projected that current capture fisheries production will not meet this growing demand. Aquaculture has the potential to mitigate the capture fishery shortfall, and the Government of Solomon Islands is prioritizing aquaculture as a solution to meet future food and income needs. Aquaculture in Solomon Islands is still in early development. Mozambique tilapia (Oreochromis mossambicus) is farmed for household consumption, but its prolific reproductive rate and resulting slow growth limit its potential as a commercial aquaculture species. More productive fish species that are not indigenous to Solomon Islands but are successfully farmed overseas could be introduced; however, such a decision needs to take into account the potential ecological or social impacts. For land-based pond aquaculture, the only indigenous species that has been farmed extensively elsewhere is milkfish (Chanos chanos). This report presents a feasibility assessment for milkfish farming in Solomon Islands. It synthesizes the current knowledge about milkfish farming and presents results of a 4-year study on the potential for milkfish aquaculture in Solomon Islands.

The commercial fishery of Lake George, Uganda (East Africa)

A shallow, highly productive, tropical lake is descrihed with a brief history of its commercial fishery. Three separate assessments of the present (1967-1970) yield are compared, with an apparent confirmation of the values derived from Fishery Department statistics over a period of 20 years. The seasonal change in the catch is noted with, an apparent anomaly shown by ohservations of canoe landings. Long-term trends during the period 1950-1969 are considered with a brief discussion of possible future trends in the fishery.

Past and present limnological investigations in Uganda: an overview

The limnological investigations in Uganda freshwaters which were started in the 1920s looked into: the origins, the changing geological and climatic factors which gave rise to the characteristic inland waters; the primary production; the constituent small aquatic organisms and their ecology; and their bordering swamps. Most of them were formed immediately after the formation of the great Western rift valley. Almost all the inland waters in Uganda are typical tropical freshwaters which, because of their relative shallowness, experience rather frequent wind stirrings and therefore nutrient circulation which would make them relatively productive. Many physical, biological and chemical factors come into play to finally determine this. The present investigations continue to bridge the gaps which were left and also to collect the baseline data needed to later manage, monitor and control any possible pollution risks.

Bibliometric analysis of biological invasions research during the period of 1991 to 2007

The objective of this study is to conduct a bibliometric analysis of all biological invasions-related publications in the Science Citation Index (SCI) from 1991 to 2007. The indicator citation per publication (CPP) was used to evaluate the impact of articles, journals, and institutions. In the 3323 articles published in 521 journals, 7261 authors from 1905 institutions of 100 countries participated. As the most productive country of biological invasions research, the US will benefit from more collaboration between institutions, countries, and continents. In addition, analysis of keywords was applied to reveal research trends.

A Review of Nontraditional Biomanipulation

The aim of this review is to identify problems, find general patterns, and extract recommendations for successful management using nontraditional biomanipulation to improve water quality. There are many obstacles that prevent traditional biomanipulation from achieving expectations: expending largely to remove planktivorous fish, reduction of external and internal phosphorus, and macrophyte re-establishment. Grazing pressure from large zooplankton is decoupled in hypereutrophic waters where cyanobacterial blooms flourish. The original idea of biomanipulation (increased zooplankton grazing rate as a tool for controlling nuisance algae) is not the only means of controlling nuisance algae via biotic manipulations. Stocking phytoplanktivorous fish may be considered to be a nontraditional method; however, it can be an effective management tool to control nuisance algal blooms in tropical lakes that are highly productive and unmanageable to reduce nutrient concentrations to low levels. Although small enclosures increase spatial overlap between predators and prey, leading to overestimates of the impact of predation, microcosm and whole-lake experiments have revealed similar community responses to major factors that regulate lake communities, such as nutrients and planktivorous fish. Both enclosure experiments and large-scale observations revealed that the initial phytoplankton community composition greatly impacted the success of biomanipulation. Long-term observations in Lake Donghu and Lake Qiandaohu have documented that silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis) (two filter-feeding planktivorous species commonly used in management) can suppress Microcystis blooms efficiently. The introduction of silver and bighead carp could be an effective management technique in eutrophic systems that lack macrozooplankton. We confirmed that nontraditional biomanipulation is only appropriate if the primary aim is to reduce nuisance blooms of large algal species, which cannot be controlled effectively by large herbivorous zooplankton. Alternatively, this type of biomanipulation did not work efficiently in less eutrophic systems where nanophytoplankton dominated.

Dietary methionine requirement for juvenile rockfish, Sebastes schlegeli

A 65-day growth trial was conducted at 19.5 degrees C to determine the optimal dietary methionine for juvenile rockfish, Sebastes schlegeli. Semipurified diets were formulated to be isonitrogenous and isoenergetic. Fish meal was used as intact protein source and crystal amino acid was used as a part of dietary protein. Six experimental diets were formulated to contain 5.8, 10.8, 15.8, 20.8, 25.8 and 30.8 g kg(-1) dietary methionine. The results showed that dietary methionine significantly affected specific growth rate, weight gain, food conversion ratio, protein productive value (PPV), energy retention efficiency, carcass index and body composition. No significant difference was found in hepatosomatic index. The dietary methionine requirement for maximum growth was 13.7 g kg(-1) dry matter or 28.0 g kg(-1) of dietary protein when cystine content was 1.2 g kg(-1) dry matter.

Effects of the phytoplanktivorous silver carp (Hypophthalmichthys molitrixon) on plankton and the hepatotoxic microcystins in an enclosure experiment in a eutrophic lake, Lake Shichahal in Beijing

The responses of nutrients, water transparency, zooplankton, phytoplankton and microcystins to a gradient of silver carp biomass (0, 18, 55, 110 g/m(3)) were assessed using enclosures in Lake Shichahai (Beijing). Picophytoplankton biomass increased with increasing fish stocking density (r=0.64, p=0.09). Silver carp significantly depressed zooplankton biomass, and thus, zooplankton grazing was too low to control phytoplankton. Intracellular microcystin (MC) content in the enclosures was correlated only to Microcystis biomass in the present study. Microcystis spp. biomass and intracellular microcystins content were much higher in lake water than those of enclosures with and without stocking fish. Stocking of silver carp could be an appropriate in highly productive Lake Shichahai, which naturally lacks of large cladoceran zooplankton. A fish stocking density of 55 g/m(3) was most efficient at controlling Microcystis blooms and increasing water clarity. Mean extracellular MC concentration in the lake water was almost the same with that of the enclosures with fish. (c) 2006 Elsevier B.V. All rights reserved.

Heavy metals in plants and phytoremediation - A state-of-the-art report with special reference to literature published in Chinese journals

Goal, Scope and Background. In some cases, soil, water and food are heavily polluted by heavy metals in China. To use plants to remediate heavy metal pollution would be an effective technique in pollution control. The accumulation of heavy metals in plants and the role of plants in removing pollutants should be understood in order to implement phytoremediation, which makes use of plants to extract, transfer and stabilize heavy metals from soil and water. Methods. The information has been compiled from Chinese publications stemming mostly from the last decade, to show the research results on heavy metals in plants and the role of plants in controlling heavy metal pollution, and to provide a general outlook of phytoremediation in China. Related references from scientific journals and university journals are searched and summarized in sections concerning the accumulation of heavy metals in plants, plants for heavy metal purification and phytoremediation techniques. Results and Discussion. Plants can take up heavy metals by their roots, or even via their stems and leaves, and accumulate them in their organs. Plants take up elements selectively. Accumulation and distribution of heavy metals in the plant depends on the plant species, element species, chemical and bioavailiability, redox, pH, cation exchange capacity, dissolved oxygen, temperature and secretion of roots. Plants are employed in the decontamination of heavy metals from polluted water and have demonstrated high performances in treating mineral tailing water and industrial effluents. The purification capacity of heavy metals by plants are affected by several factors, such as the concentration of the heavy metals, species of elements, plant species, exposure duration, temperature and pH. Conclusions. Phytoremediation, which makes use of vegetation to remove, detoxify, or stabilize persistent pollutants, is a green and environmentally-friendly tool for cleaning polluted soil and water. The advantage of high biomass productive and easy disposal makes plants most useful to remediate heavy metals on site. Recommendations and Outlook. Based on knowledge of the heavy metal accumulation in plants, it is possible to select those species of crops and pasturage herbs, which accumulate fewer heavy metals, for food cultivation and fodder for animals; and to select those hyperaccumulation species for extracting heavy metals from soil and water. Studies on the mechanisms and application of hyperaccumulation are necessary in China for developing phytoremediation.

STUDIES ON MIXED MASS CULTIVATION OF ANABAENA SPP (NITROGEN-FIXING BLUE-GREEN-ALGAE, CYANOBACTERIA) ON A LARGE-SCALE

Studies on mixed mass cultivation of Anabaena spp. on a large scale (5170 m2) were conducted continuously for 3 years. Under the continental monsoon climate in northern subtropics (30-degrees-N, 115-degrees-E), 7-11 g dry weight m-2 day-1 of microalgal biomass on average was harvested in simple plastic greenhouses in the effective growth days during the warmer seasons. The maximum productivity was 22 g m-2 day-1 in the middle of summer. Observations on the productive properties of strains of Anabaena spp. indicated that they were different from and could compensate for each other in their productivities and adaptations to the seasonal changes. With different lining materials (PVC sheets, concrete, sand and soil) in the culture ponds, no significant variation of productivity was found, but bubbling with biogas in the middle of the day and the application of some growth regulating substances (2,4-D, NaHSO3 and extracts of oyster mushroom spawn) was able to improve the production. The cost of microalgal biomass in this way was around 0.75-1.0 US dollar(s) per kilogram.

黄土高原六盘山生态经济圈功能区规划研究

六盘山区位于黄河中上游,是黄土高原西部天然生态屏障和水源涵养区,在中国生态环境建设中具有重要战略地位。本区土地资源丰富,生态环境洁净,旱作农业潜力大,草畜业兴旺。六盘山生态经济圈规划了4个功能区和7大特色农业基地产业,以六盘山国家自然保护区为中心,加大退耕造林种草与管护力度,到2015年基本修复六盘山区受损的森林生态系统和灌丛草原植被;以旱作农业技术体系为支撑,建立高效可持续发展的生态农业系统和绿色农牧产品基地,为经济社会发展和新农村建设提供良好的生态环境和农业基础。

Applications of Heavy Ion Irradiation in Photonic Crystal Research

Photonic crystals (PC) have received extensive attention for the photonic band gap (PBG). The polystyrene (PS) particles bottom-up approach is a productive method for photonic crystal manufacture, this kind of photonic crystals having an unique PBG that depends on the particle's shape, sizes and defects. Heavy ion irradiation is a very useful method to induce defects in PC and change the shapes of the particles to tune the PBG. MeV heavy ion irradiation leads to an anisotropic deformation of the particles from spherical to ellipsoidal, the aspect ratio of which can be precisely controlled by using the ion energy and flux. Sub-micrometer PS particles were deposited on a Cu substrate and were irradiated at 230 K by using heavy ion energy and fluence in the range from 2 to 10 MeV and 1 x 10(14) cm(-2) to 1 x 10(15) cm(-2); respectively.

Applications of Heavy Ion Irradiation in Photonic Crystal Research

Photonic crystals (PC) have received extensive attention for the photonic band gap (PBG). The polystyrene (PS) particles bottom-up approach is a productive method for photonic crystal manufacture, this kind of photonic crystals having an unique PBG that depends on the particle's shape, sizes and defects. Heavy ion irradiation is a very useful method to induce defects in PC and change the shapes of the particles to tune the PBG. MeV heavy ion irradiation leads to an anisotropic deformation of the particles from spherical to ellipsoidal, the aspect ratio of which can be precisely controlled by using the ion energy and flux. Sub-micrometer PS particles were deposited on a Cu substrate and were irradiated at 230 K by using heavy ion energy and fluence in the range from 2 to 10 MeV and 1 x 10(14) cm(-2) to 1 x 10(15) cm(-2); respectively.

青杨(Populus cathayana Rehd)雌雄植株对锈病和干旱胁迫的生理响应及差异蛋白质组比较

雌雄异株植物对环境的不同响应一直是一个有趣而新颖的研究领域，由于雌雄个体不同的繁殖成本及不同的生存策略，使得雌雄植株在生长、存活、生殖格局、空间分布、资源配置等方面已经表现出明显的不同，在生理和分子水平上也表现出明显的性别间差异。干旱是制约农林业发展的环境因子之一，叶锈病是对杨树危害最严重的病害之一，由于长期进化的结果，不同性别的植物必然对生物和非生物胁迫有着不同的响应。本文以雌雄异株的青杨为模式植物，研究雌雄间在生理、生化、亚细胞结构和蛋白质水平上对生物和非生物胁迫的差异响应。主要研究结果如下： （1） 青杨雌雄植株对锈病胁迫的生理生化差异响应 在正常的对照组中，雄株叶片比雌株叶片有着较高的活性氧自由基产生速率、较高的SOD、POD、PPO 和较低的CAT 活性；在锈病感染的早期阶段， SOD、POD、CAT 活性、活性氧自由基产生速率、H2O2 含量、膜脂过氧化程度和细胞膜的电渗率在雌雄株中都增加，而PPO 仅在雄株中增加明显，APX 仅在雌株中增加明显，并且雌株比雄株有着更严重的锈病感染程度、细胞膜的伤害程度和光合系统II 的破坏程度，雌株有更多的净光合速率、气孔导度和叶绿素a 含量的降低，在同工酶变化上，雌雄间对锈病也显示出不同的表达模式。结果显示，雄株比雌株对锈病有着更好的抗性和更有效的ROS 清除系统。 （2） 青杨雌雄植株对干旱胁迫的生理生化及亚细胞结构的差异响应 与较好水分条件相比，干旱下雄株比雌株有着更高的A-Ci 响应参数，如Rubisco 最大羧化速率、光呼吸速率、暗呼吸速率和最大电子传递速率等。干旱显著地增加了膜脂过氧化程度和游离脯氨酸含量，并且雄株比雌株表现出较低的膜脂过氧化程度，较高的总蛋白和游离脯氨酸含量。无论是中度干旱还是极度干旱，除了CAT 外，雄株比雌株表现为较强的抗氧化酶活性，在同工酶谱带上，雌雄间表现出不同的变化模式，并且有些条带是干旱影响应的，而有些条带是性别特异性的，这些性别特异性条带能够作为鉴定性别快速而准确的标记。干旱显著地影响了线粒体、叶绿体和细胞壁的结构，尤其在中度干旱胁迫下，雄株线粒体和叶绿体比雌株呈现出较好的完整性，并且雄株细胞壁要比雌株更厚。因此， 雄株比雌株表现出更强的干旱忍耐性和更高效的抗氧化酶系统。 （3） 青杨雌雄植株对干旱胁迫的蛋白质组差异响应 用双相电泳检测到雌雄间近1000 个蛋白点，通过对比发现对照组雌雄间有54 个差异蛋白点，干旱下雌雄间有108 个差异点，其中102 个被质谱成功鉴定。对照组雌雄间的差异蛋白主要集中在与光合作用相关蛋白、抗氧化酶、胁迫防御蛋白和一些调节基因表达的蛋白；干旱胁迫下雌雄间差异蛋白明显增多，主要有参与信号转导、调节基因表达、蛋白质加工、转录产物的转录翻译后修饰的调节性蛋白蛋白和参与氧化还原平衡、抗胁迫、细胞壁合成、光合作用、能量代谢、氨基酸代谢和脂肪酸代谢等的功能性蛋白。干旱下这些蛋白的表达量在雌雄中有的表现出相同的表达模式，如干旱下雌雄株中Rubisco 激活酶、小热激蛋白等表达都增加，而有的表现出相反的表达模式，如Rubisco 大亚基的降解片段、羰酸酯酶等在雄株中表达量上调而在雌株中却是下调。因此，雌雄间在蛋白质水平上对干旱胁迫响应的差异是显著的，也是复杂的。 It is an interesting and novel topic that dioecious plants possess different responses to environmental stress. As for the different productive cost and different survive strategy, different sexual plants have shown obviously morphological, physiological and molecular differences. Drought is one of the most worldwidely important environmental stress factors that limit plant growth and ecosystem productivity. Rust disease is one of the economically important diseases in many trees. As a result of the long evolutionary process, male and female plants should show different responses to abiotic and biotic stress. In this paper, using a dioeious tree of Populus cathayana Rehd as a model, we study the sexual differences to drought and rust disease stress in physiological, biochemical, sub-cellular and proteomics levels. The main results are follows: (1) The sexual differences in physiology and biochemistry of poplar to rust disease In controls, males showed higher production of superoxide radicals, higher activities of SOD, POD, PPO and lower CAT activity. Under rust disease, the activities of antioxidant, the content of ROS and the degree of cellular member destroyed were increased in both sexes, except for PPO in diseased males and APX in diseased females. However, females showed more seriously disease severity and cellular member and PS II destroyed degrees. Net photosynthesis rate, transpiration rate and chlorophyll a content were decreased more in diseased females than in males. There were also some different changes inantioxidant isozymes under rust disease. The results suggested that male poplar possessed a more effectively antioxidant system and were more resistant to rut disease than females. (2) The sexual differences in physiology and biochemistry of poplar to drought stress Under drought stress, there were higher rates of RuBP-saturated CO2 assimilation, dark respiration, photorespiratory release of oxygen, the max electron transportrate in CO2-saturated and carboxylation efficiency in males than in females. And males showed lower TBARS and higher proline content. Except for CAT, the activities of other antioxidants were higher in males than in females. Meanwhile, there were obviously differences in isozyme changes between teo sexes. Drought stress obviously destroyed the integralities of chloroplasts and mitochondria and the sexual differences in sub-cellular level were obviously under the moderate water stress. Male cell walls were more sensitive to drought stress than did female. The results suggested males were more resistant to drought stress. (3) The sexual differences in proteomics of poplar to drought stress By 2-D and MS analysis, we identified 102 different protein spots between males and females. Under control conditions, the different proteins were mainly in photosynthesis related proteins, antioxidants, stress response proteins and some gene expression related proteins. Under drought stress, the different proteins were focused on (i) regulated proteins such as signaling conduction, kinase, HSP, gene expressional regulation and protein modification, (ii) functional proteins such as photosynthesis, energy metabolism, antioxidant, redox, stress response, lipid metabolism and amino acid metabolism. Some protein showed the same expressional pattern, while some showed contrary expressional pattern. Thus, the results suggested that sexual differences in proteomics were significant and complex.