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71.
绿色杷夫藻用于罗氏沼虾人工生态系育苗 总被引:3,自引:0,他引:3
本文通过培养试验探讨了绿色杷夫藻(Pavlovaviridis)的生长特性,认为该藻具有指数生长期较长、藻群绝对密度较高且维持高峰时间较长等优良特性。该藻具有较广泛的生态适应性,能适应光强500~10000lx、温度6~30℃、海水比重1.002~1.016,特别能在低盐度(比重为1.002)、低光照(400~500lx)条件下良好生长,生态上符合罗氏沼虾人工育苗的客观要求。在育苗水体中保持一定数量饵料性微藻并投饲其他生物饵料构成人工生态育苗体系进行工厂化育苗,以角毛藻(Chaetocerossp.)、小球藻(Chlorellasp.)为对照,比较3种微藻培育罗氏沼虾状幼体的效果,发现绿色杷夫藻与角毛藻效果相当而明显好于小球藻。本文作者认为绿色杷夫藻是罗氏沼虾人工生态系育苗的理想用藻。 相似文献
72.
The glucosinolate make‐up of the edible parts of some Brassica oleracea L. crops has been investigated previously, but the leafy‐green collard (B. oleracea var. viridis) remains relatively unstudied on this topic. Due to this lack of information, a collection of US landraces was examined for glucosinolate content of leaves. The specific objectives of this examination were to compare levels of certain glucosinolates among the conserved collard landraces, identify any individuals with a distinct glucosinolate profile and determine the potential of collard as a target for chemoprotective‐based plant breeding. During winter 2010/2011, 81 collard landraces, four other viridis and four collard cultivars were evaluated in the field and harvested leaves were assayed for glucosinolates. In a subsequent study, 19 selected landraces plus the cultivars were included in a repeat trial in 2012/2013. Eighteen collard landraces contained relatively high levels of glucoraphanin in leaves in both years, and three (designated G 32575, G 32580, G 32586 in the US National Plant Germplasm System) were found to contain glucoraphanin in excess of 9.5 μmol/g DM. The examined landraces are rich sources of important aliphatic glucosinolates, previously thought to be most abundant in other B. oleracea vegetables. 相似文献
73.
Molecular evidence of biased inheritance of trifluralin herbicide resistance in foxtail millet 总被引:2,自引:0,他引:2
Inheritance of trifluralin herbicide resistance was investigated for phenotype and genotype (molecular identification) in 12 segregating populations derived from crosses between resistant green foxtail (Setaria viridis) and foxtail millet cultivars (S. italica). Combining a herbicide bioassay and a bidirectional allele‐specific polymerase chain reaction (PCR) assay, the trifluralin resistance in foxtail millet was proved to be conferred by a recessive α2‐tubulin gene mutation at Ile‐239, the allele transferred by green foxtail. However, a distorted segregation ratio in F2 populations was confirmed, with 16.9% resistant plants on average instead of the 25% expected for a single gene recessive mutation. This was not due to non‐germinating seed and the distortion was also observed in the next generations, indicating a heritable phenomenon. After further crosses and self‐fertilization, however, more advanced generations did not show the same pattern of skewed inheritance as in the early generations. These results suggest the possibility of linkage between the α2‐tubulin gene and a modifier gene to explain the distorted segregation, which might be broken by crossing over. 相似文献
74.
75.
Andrea C. Alfaro Brent R. Copp David R. Appleton Shane Kelly Andrew G. Jeffs 《Aquaculture International》2006,14(4):405-412
The large (70,000 tonnes) mussel aquaculture industry for the endemic New Zealand green-lipped mussel, Perna canaliculus Gmelin, currently relies almost entirely (80%) on wild caught seed that is often harvested attached to great quantities of floating algae. Natural vagaries in catches of wild mussel seed frequently result in shortages of mussel seed that, at times, have severely affected commercial aquaculture production. Both field and laboratory experiments were used to establish that chemical cues derived from algae significantly increase settlement of mussel larvae on artificial substrates. This is the first time an algal chemical cue has been implicated in the settlement behavior of P. canaliculus larvae. These results have potential commercial implications for improving mussel seed supply through inducing higher or more reliable levels of mussel settlement for aquaculture seed collection. 相似文献
76.
[目的]提取翡翠贻贝多糖和牡蛎多糖并评价其生物活性,为这两种贝类多糖的开发利用提供科学依据.[方法]采用酶解法提取翡翠贻贝多糖和牡蛎多糖,并采用苯酚—硫酸比色法测定其多糖中的总糖含量;通过纸片扩散法、清除羟基自由基(·OH)试验和MTT法分别评价两种多糖的体外抑菌活性、抗氧化活性及抗猪蓝耳病毒(PRRSV)活性.[结果]翡翠贻贝多糖和牡蛎多糖提取率分别为0.21%和0.14%,其多糖中的总糖含量分别为90.2%和90.1%.翡翠贻贝多糖和牡蛎多糖对·OH均有一定的清除作用,且随多糖质量浓度的增加而逐渐增强;对金黄色葡萄球菌和大肠杆菌均无明显的抑制作用;对PRRSV均无明显的阻断、抑制及直接杀灭作用.[结论]翡翠贻贝多糖和牡蛎多糖均具有一定的抗氧化活性,但不显示有意义的体外抑菌和抗PRRSV活性,可将其作为抗氧化剂资源予以研究. 相似文献
77.
The effect of temperature on the development, growth, survival and settlement of Perna viridis was studied under controlled conditions to provide information needed for the development of commercial hatchery technology for green mussel P. viridis. Total mortality of the larvae occurred after 24 h at temperatures of 33°C and 35°C. At 24°C, larvae took longer to settle than at temperatures of 27°C, 29°C and 31°C. For optimum larval development (8–13 h), growth (17.2±0.84 μm day–1) and survival (55.2±0.84%), a hatchery rearing temperature of 31°C is required. For settlement no significant difference was seen between the percentage settlement at 29°C (49.3±3.34%) and 31°C (45.8±1.76%). However, the process of settlement began and ended earlier at 29°C (from 15 to 18 days) than at 31°C (from 18 to 20 days). Thus for larval settlement a temperature of 29°C is recommended. 相似文献
78.
Osteoarthritis (OA) typically generates pain, reduced mobility and reduced quality of life. Most conventional treatments for osteoarthritis, such as non-steroidal anti-inflammatory drugs (NSAIDs) and simple analgesics, have side effects. PCSO-524™, a non polar lipid extract from the New Zealand Green Lipped Mussel, is rich in omega-3 fatty acids and has been shown to reduce inflammation in both animal studies and patient trials. This OA trial examined pain relief changes in relation to quality of life and safety of use for OA patients who took PCSO-524™ compared with patients who took fish oil (containing an industry standard EPA-18% and DHA-12% blend). PCSO-524™ patients showed a statistically significant improvement compared with patients who took fish oil. There was an 89% decrease in their pain symptoms and 91% reported an improved quality of life. Patients treated with fish oil showed significantly less improvement and a greater level of physical discomfort during the study. These results suggest that PCSO-524™ might offer a potential alternative complementary therapy with no side effects for OA patients. 相似文献
79.
80.
新疆天山野生草莓与绿色草莓(Fragaria viridis Duch.) 同一性的鉴定 总被引:7,自引:0,他引:7
通过植物学性状观察和RAPD 技术鉴定证明新疆天山野生草莓为绿色草莓(Fragaria viridis Duch. ) , 表明中国自然分布的草莓野生种达到9 个。绿色草莓在分类学上的典型特征为匍匐茎上从第二节开始每节均形成幼苗; 花序直立、高于叶面, 花瓣显露时呈黄绿色,雄蕊花丝细长, 高于雌蕊; 果实圆形或扁圆形, 淡绿色, 阳面略红, 果硬, 成熟时萼片紧贴,脱萼难。 相似文献