纵条纹炭角菌的研究进展

纵条纹炭角菌具有镇静、催眠等药用价值,已实现工厂化、规模化栽培。为探究纵条纹炭角菌的研究进展,对其分类学地位、生物学特性、人工培养、化学成分和生理活性等方面的文献进行综述,并提出未来研究的方向和应用前景。     

Inducing synchronous ovarian maturation in the crayfish,Procambarus clarkii,via eyestalk interventional injection as compared with eyestalk ablation and combined injection of serotonin and domperidone

We examined the feasibility of inducing synchronous ovarian maturation in the crayfish, Procambarus clarkii, via eyestalk interventional injection (EI) using a Bletilla striata polysaccharide (BSP) gelatin containing tranexamic acid (TRA), domperidone (DOM) or serotonin (5‐HT). In total, 360 females were randomly assigned to seven experimental groups and a control group. The average survival rate (SR%) and average synchronous ovarian maturation rate (SMR%) in survivors in the EI groups, EI‐TRA, EI‐DOM, EI‐5HT were compared with bilateral eyestalk ablation (BEA), unilateral eyestalk ablation (UEA), abdominal injection (AI) of DOM (0.5 mg crayfish^?1) alone (AI‐DOM) or combined with 5‐HT (0.5 mg crayfish^?1) (AI‐DOM+5‐HT). The experiment covered a prolonged period of 32 days until two ovigerous females were observed in BEA. EI‐DOM achieved a SMR (66.67 ± 9.62%) higher than the control (22.05 ± 3.06%) (P < 0.05), but lower than BEA (88.89 ± 11.11%), UEA (63.33 ± 18.56) and AI‐DOM+5‐HT (59.26 ± 10.14%) (P > 0.05). EI‐DOM also achieved a higher SR (53.33 ± 3.85%) than BEA (15.56 ± 2.22), UEA (24.44 ± 5.88) (P < 0.05) and AI‐DOM+5HT (51.11 ± 4.44) (P > 0.05). However, EI‐TRA (SR = 28.89 ± 4.44, SMR = 37.78 ± 2.22) and EI‐5‐HT (SR = 15.56 ±4.44, SMR = 22.22 ± 11.11) failed to induce significantly higher SMR than the control. These findings suggest that EI methods, such as EI‐DOM, may have positive characteristics for the development of inexpensive and less labour‐intensive techniques for induction of ovarian maturation in decapods.     

白及组织培养技术研究现状

该文对关于白及组织培养技术的研究报道进行了梳理与总结,对白及组织培养外植体,愈伤组织诱导增殖分化,生根培养及移栽,生长调节剂的作用及外界环境影响进行了阐述,为进一步深入研究提供理论支持.     

生态环境因子对白芨生长发育的影响

研究不同栽培基质、根外追肥、光照条件对白芨(Bletilla striata (Thunb.) Reichb. f.)生长发育的影响,确定适宜的栽培基质配比、根外追肥施用方案以及光照条件,为其科学的栽培方式提供理论依据。选用三年生白芨作为试验材料,通过引种驯化、基质配比、根外追肥、光照条件等处理下白芨各农艺性状和叶绿素含量进行测定及比较分析,开展白芨引种和规范化栽培技术研究。结果表明,白芨在基质配比为农田原土：白沙=2:2的条件下栽植,其生长状况仅次于营养土,但成本低,有利于适应大田栽培；叶面喷施KH2PO4溶液可促进白芨的生长发育,尤以浓度为2‰时效果最显著；适当的遮阴度有利于白芨的生长发育,但当遮阴度达到70%以上时,白芨群体花期、单株开花量明显低于其他处理,抑制了白芨繁殖器官的发育。     

锰胁迫下鸡眼草的富集特征及生理响应

为探明植物对锰胁迫的耐受性机制,以采自重金属污染区与非污染区的鸡眼草为试验材料,在不同锰浓度胁迫下［0 （对照）、1000、5000、10000、15000、20000 μmol·L^-1］ 开展盆栽试验,比较研究锰胁迫对两种来源鸡眼草表型、生理生化特性及锰积累特征的影响。结果表明：随着锰浓度的升高,1） 两种来源鸡眼草的根干重、芽干重、根冠比均呈降低的趋势;当锰浓度达5000~20000 μmol·L^-1时,与对照相比,污染区、非污染区鸡眼草的芽干重分别下降4.34%~27.71%与16.33%~49.77%,根干重分别下降19.00%~66.06%与27.90%~77.54%,污染区下降幅度均较非污染区的小;2） 两种来源鸡眼草的叶绿素、可溶性糖、脯氨酸含量及超氧化物歧化酶（SOD）、过氧化物酶（POD）活性均呈先升后降的趋势,可溶性蛋白含量逐渐下降,丙二醛（MDA）含量则逐渐升高;3） 两种来源鸡眼草根、茎、叶的锰含量均增加;锰浓度为20000 μmol·L^-1时,污染区和非污染区鸡眼草的叶锰含量分别为对照的16.53和13.41倍。因此,污染区鸡眼草锰耐受能力及富集能力均较非污染区鸡眼草高,较高的抗氧化酶活性是其耐受高锰胁迫的重要生理机制。     

Effects of dietary docosahexaenoic acid (22:6n‐3) and arachidonic acid (20:4n‐6) on the growth,survival, stress resistance and fatty acid composition in black sea bass Centropristis striata (Linnaeus 1758) larvae

The objectives of this study were to determine the effects of the dietary docosahexaenoic acid (DHA) to arachidonic acid (ARA) ratio on the survival, growth, hypersaline stress resistance and tissue composition of black sea bass larvae raised from first feeding to metamorphic stages. Larvae were fed enriched rotifers Brachionus rotundiformis and Artemia nauplii containing two levels of DHA (0% and 10% total fatty acids=TFA) in conjunction with three levels of ARA (0%, 3% and 6% TFA). On d24ph, larvae fed the 10:6 (DHA:ARA) treatment showed significantly (P<0.05) higher survival (62.3%) than larvae fed 0:0 (DHA:ARA) (27.4%). Notochord length and dry weight were also significantly (P<0.05) greater in the 10:6 (DHA:ARA) treatment (8.65 mm, 2.14 mg) than in the 0:0 (DHA:ARA) (7.7 mm, 1.65 mg) treatment. During hypersaline (65 g L⁻¹) challenge, no significant differences (P>0.05) were observed in the median survival time (ST50) between larvae fed 10% DHA (ST50=25.6 min) and larvae fed 0% DHA (ST50=18.2 min). The results suggested that black sea bass larvae fed prey containing 10% DHA with increasing ARA within the range of 0–6% showed improved growth and survival from first feeding through metamorphic stages.     

The effects of temperature on sex differentiation and growth of black sea bass (Centropristis striata L.)

To examine the effects of temperature on sex differentiation in the black sea bass ( Centropristis striata L.), a protogynous hermaphrodite, juveniles (∼0.5 g) were cultured in recirculating systems at 17, 21 or 25 °C. Growth was assessed at 155, 182, 241 and 275 days post hatch and sex differentiation was determined histologically. No differences were found in the sex ratios of fish reared at different temperatures, but only 55–64% developed as females. Growth was significantly greater in males across all temperature treatments. These results suggest that black sea bass exhibit sexually dimorphic growth patterns and that female-specific sex determination can be disrupted in culture.     

Dispersal of black sea bass (Centropristis striata) larvae on the southeast U.S. continental shelf: results of a coupled vertical larval behavior – 3D circulation model

In the marine environment, pelagic dispersal is important for determining the distribution and abundance of populations, as well as providing connections among populations. Estimates of larval dispersal from spawning grounds are important to determining temporal and spatial patterns in recruitment that may have significant influences on the dynamics of the population. We present a case study of the dispersal of Centropristis striata (black sea bass) larvae on the southeast U.S. continental shelf. We use a coupled larval behavior – 3D circulation model to compare the effects of the timing and location of spawning against that of larval vertical migration on larval dispersal. Using the results of field data on larval vertical distributions, we compare the dispersal of virtual 'larvae' which have ontogenetic changes in vertical behavior with that of particles fixed near the surface and near the bottom. Larvae were released at potential spawning sites four times throughout the spawning season (February through May) for 3 yr (2002–04) and tracked for the assumed larval duration (from 27 to 37 days including the egg stage). Results indicate that adult behavior, in the form of spawning time and location, may be more important than larval vertical behavior in determining larval dispersal on the inner- and mid- continental shelves of this region.     

美洲黑石斑鱼的品种优势和养殖前景

美洲黑石斑鱼属于鮨科Serranidae,石斑鱼亚科Serraninae,俗名有翡翠斑、珍珠斑等美称,是美国近年成功开发的一个新养殖鱼种。它的养殖和市场潜力巨大,活鱼和加工产品极受美国和加拿大消费者的欢迎。我国从2003年引进,试养效果良好;2006年大规模生产苗种达100余万尾,为在我国推广养殖奠定了基础。本文重点介绍了该品种的生物学特性、养殖潜力、商业价值和在我国推广养殖的可行性,认为该品种很适合我国东部和东南沿海温带和亚热带水域开展深水网箱、工厂、池塘等模式的养殖,预测产品不仅可以内销而且有望远销欧美各国。