Harvest of Channel Catfish with an Electrically Enhanced Seine     

C. Douglas  Minchew  Kenneth K.  McDill Rachel V.  Beecham S. D. Filip To   《Journal of the World Aquaculture Society》2004,35(4):543-545

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The Characterization of Heavy Metals in the Grapevine (Vitis vinifera) Cultivar Rkatsiteli and Wild Blackberry (Rubus fruticosus) from East Serbia by ICP-OES and BAFs     

Slađana Č. Alagić  Snežana B. Tošić  Mile D. Dimitrijević  Jelena V. Petrović  Dragana V. Medić 《Communications in Soil Science and Plant Analysis》2016,47(17):2034-2045

Inductively coupled plasma optical emission spectroscopy, in combination with calculation of various biological factors, was used in this study not only for a simple illustration of the present status of some essential and non-essential metals such as copper (Cu), zinc (Zn), nickel (Ni), lead (Pb), arsenic (As), and cadmium (Cd) in the grapevine cultivar Rkatsiteli and wild blackberry from East Serbia but also for the estimation of plant bioaccumulation potentials. Great majority of detected metal concentrations were in normal ranges except in few cases: Zn concentrations were at the level of deficiency in almost all plant parts, and some Cu and As concentrations were at the levels that could be considered phytotoxic. Biological accumulation factors provided very informative data on metal accumulation and translocation in both plants and pointed to low accumulation rates of metals except in the case of Cu, Zn, and As in some wild blackberry tissues.  相似文献   

Nitrous Oxide and Carbon Dioxide Emissions from Vietnamese Soil Amended with Different Compost Types at High Temperature     

Van Ngoc Tuong Hoang 《Communications in Soil Science and Plant Analysis》2018,49(7):848-861

This study aims to determine the effects of compost additions and high temperature on N₂O and CO₂ emissions from a Vietnamese agricultural soil. Soil samples amended with two compost types (commercial compost, SH and chicken compost, CC) at three rates of 1%, 2% and 4% w/w were aerobically incubated at 25°C, 30°C and 35°C for 28 days in the laboratory. N₂O and CO₂ emissions were determined on days 1, 3, 5, 7, 14, 21 and 28. Our results showed that N₂O and CO₂ emissions were significantly affected by temperature, compost additions, and their interactions. Greater N₂O and CO₂ emissions were seen in CC treatments than SH treatments. Higher application rates of CC led to greater N₂O and CO₂ emissions. In SH treatments, higher temperature lowered N₂O emissions but did not affect CO₂ emissions. N₂O and CO₂ emissions were enhanced with CC addition while they showed different responses to increasing temperature.  相似文献   

Assessing freeze-tolerance in St. Augustinegrass: temperature response and evaluation methods     

Jennifer A. Kimball  Tan D. Tuong  Consuelo Arellano  David P. Livingston III  Susana R. Milla-Lewis 《Euphytica》2017,213(5):110

Winter hardiness is a major-limiting factor for St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] grown in the transitional climatic region of the United States. Lab-based freeze tests that mimic the range of field winter survivability in St. Augustinegrass can contribute to the selection of cold hardy genotypes. This study used a whole container method, four freezing temperatures, and two data collection systems to evaluate the freezing response of nine St. Augustinegrass genotypes ranging in their winter hardiness. Results indicated ?3 and ?4 °C with average regrowth ratings of 33.6 and 17.8% respectively, were more suitable temperatures for evaluating freeze survival in St. Augustinegrass than ?5 and ?6 °C with average regrowth ratings of 0.4 and 0%, respectively. Visual ratings of surviving green tissue and regrowth were generally well correlated when evaluated over a six week period post-freeze with Pearson correlation coefficients ranging of 0.17–0.62  for ?3 °C freeze tests and 0.79–0.93 for ?4 °C freeze tests. Additionally, measurement of percent green cover using digital imaging techniques commonly utilized in turfgrass field studies were significantly correlated (0.66) with visual ratings averaged across weekly post-freeze evaluation measurements for both ?3 and ?4 °C freezing temperatures. These results provide evidence that digital imaging analyses are useful in estimating surviving green tissue and regrowth in lab-based freeze tests. This study provides additional information regarding freezing temperatures, genotype responses, and data collection methods in St. Augustinegrass, which should aid breeders in the improvement of freeze tolerance in the species.  相似文献   

Long‐term field insecticide susceptibility data and laboratory experiments reveal evidence for cross resistance to other neonicotinoids in the imidacloprid‐resistant brown planthopper Nilaparvata lugens     

Tomohisa Fujii  Sachiyo Sanada‐Morimura  Takaho Oe  Manami Ide  Dinh Van Thanh  Ho Van Chien  Phan Van Tuong  Phung Minh Loc  Le Quoc Cuong  Ze‐Wen Liu  Zeng‐Rong Zhu  Jian‐Hong Li  Gang Wu  Shou‐Horng Huang  Gerardo F Estoy  Shoji Sonoda  Masaya Matsumura 《Pest management science》2020,76(2):480-486

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Should only females of giant freshwater prawn Macrobrachium rosenbergii be selected in genetic improvement programmes?     

Nguyen Thanh Vu  Tran Huu Phuc  Nguyen Trung Ky  Nguyen Thi Kieu Nga  Nguyen Hong Nguyen 《Aquaculture Research》2020,51(4):1381-1387

Sexual dimorphism is widely observed in almost all farmed aquatic animal species but giant freshwater pawn (GFP) is unique, with males characterized by three main morphotypes (blue claw, orange claw and small males) and females by different reproduction status (ovary, berried egg and already‐spawned females). There has been reported evidence that the effect of male morphotype may have masked genetic variation in growth‐related traits, as a result the heritability for male body weight was lower than that estimated in female. A pending question has arisen whether selection should be made in female only. To answer this question, we used an 8‐year data set from a long‐term selection programme (2008–2015) for high growth in this species comprising 106,756 individuals that were offspring of 515 sires and 810 dams. The body weight data of female and male GFP or of each morphotype was treated as a separate trait and a multi‐trait approach was used to estimate genetic correlations for homologous traits between sexes and between morphotypes. Our analysis showed that there were little differences in the heritability estimates between female and male. In female, mature ovary individual displayed higher heritability than berried egg and already‐spawned females. For male, the heritability for blue claw, orange claw and small males were 0.11, 0.06 and 0.00 respectively. Between‐sex genetic correlation was moderate (0.55 ± 0.11) for body weight, suggesting that the trait expressions in female and male may be genetically different. In female, the genetic correlations for body weight among three female types were close to one (0.91–0.94). In contrast, the genetic correlations for body weight between male morphotypes especially between blue claw or orange claw and small males were low (0.15–0.25). Furthermore, we estimated genetic gain as the difference in least square means (LSM) or estimated breeding values (EBV) between the selection line and control group. The genetic gain in body weight was smaller in females than in males. It is concluded that there is no need to run separate breeding programme for female and male GFP. A combined selection using both female and male data can achieve selection response for body weight as demonstrated in the present study.  相似文献   

Genital Disorders,Linear and Testicular Characteristics in Menz Rams     

Hibret A  Toé F  Mukasa-Mugerwa E  Kassa T  Markos T 《Tropical animal health and production》2001,33(3):219-227

Clinical examination, bodily condition score (BCS), heart girth (HG), body length (BL), wither height (WH), and scrotal circumference (SC) were assessed on 486 mature Ethiopian Menz rams, on small farms, in local markets, and at the main abattoir in Addis Ababa from December 1994 to April 1995. Almost 27% of the rams were found to be unfit for breeding. Poor general condition, mainly in the form of respiratory disorders, was seen in 1.2% of the rams. Balanoposthitis, epididymitis and orchitis were the most common pathological conditions, affecting the external reproductive organs in 14.6%, 4.5% and 4.1% of the rams, respectively. Testicular calcification, cysts and testicular haemorrhagic lesions were detected in 4, 6 and 8, respectively, of the 60 rams examined at necropsy. The BCS, HG, BL and WH averaged 2.1±0.5, 67.7±5.0 cm, 60.1±4.5 cm and 60.1±4.3 cm, respectively. The mean SC was 25.5±3.9 cm and did not vary significantly with age (p>0.05). Among the linear body measurements, the highest correlation was between BL and WH (r = 0.66). SC was found to be most closely correlated to HG (r = 0.46). More investigations into the relationship between the present findings and actual fertility, and on their practical application in the selection of rams for breeding is recommended.  相似文献   

Roles of stolbur phytoplasma and <Emphasis Type="Italic">Reptalus panzeri</Emphasis> (Cixiinae,Auchenorrhyncha) in the epidemiology of Maize redness in Serbia     

J. Jović  T. Cvrković  M. Mitrović  S. Krnjajić  Margaret G. Redinbaugh  R. C. Pratt  R. E. Gingery  S. A. Hogenhout  I. Toševski 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(1):85-89

Maize redness (MR), a disease causing midrib, leaf and stalk reddening and abnormal ear development in maize, has been reported from Serbia, Romania and Bulgaria for 50 years. Recent epiphytotics reduced yields by 40%–90% in southern Banat, Serbia. MR was recently associated with the presence of the stolbur phytoplasma, although the epidemiology of the disease remained unknown. Diseased fields in southern Banat were surveyed for potential vectors of the phytoplasma during 2005 and 2006, and high populations of Reptalus panzeri were found. In affected fields, 20% of the R. panzeri individuals and 85% of symptomatic maize plants carried the stolbur phytoplasma. When stolbur phytoplasma-infected R. panzeri were introduced into insect-free mesh cages containing healthy maize plants, midrib and leaf reddening developed on 48% of plants and stolbur phytoplasma was detected in 90% of the symptomatic plants. No symptoms or phytoplasma-positive plants were found in cages without insects. These data indicate that MR symptoms are associated with the stolbur phytoplasma. Reptalus panzeri is both abundant in affected fields and can transmit the stolbur phytoplasma, indicating the insect is likely to be a major vector of MR.  相似文献   

七个突破性经营策略     

Steve Tobak 《中国禽业导刊》2012,(17):30-30

每天，我们的收件箱和垃圾箱中充满了许诺重大效果的电子邮件，诸如“提高搜索引擎中的排名”以及“揭秘你的秘密销售力量”，更不必说那些“想要建立联系”或希望“只占用你15分钟”的名流了。而这只是上周收到的一小部分!  相似文献   

In vitro interaction of some drug combinations to inhibit rapidly growing mycobacteria isolates from cats and dogs and these isolates' susceptibility to cefovecin and clofazimine          下载免费PDF全文

CJM Bennie  JLK To  PA Martin  M Govendir 《Australian veterinary journal》2015,93(1-2):40-45

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