基于12SrRNA和ND3基因序列分析巨[鱼丕]遗传多样性及系统进化

为从分子水平研究巨[鱼丕](Bagarius yarrelli Sykes)的遗传多样性和系统进化关系,本实验对采集于怒江、澜沧江、元江3河流5种群中的60个个体进行12S rRNA和ND3基因序列的PCR扩增,同时与红河河口群体12个个体的12S rRNA和ND3基因序列进行比对分析,采用Mega5.02软件对碱基组成、Kimura-2 parameter遗传距离、可变位点等进行分析。应用DnaSP软件进行遗传多样性相关参数的计算。结果显示:12S rRNA和ND3基因序列长度分别为954 bp和346 bp(349 bp),分别定义了51个单倍型和42个单倍型,12S rRNA和ND3序列中的碱基平均含量分别为:T为20.8%、C为25.7%、A为32.1%、G为21.4%和T为29.5%、C为28.2%、A为28.1%、G为14.1%,表现出明显的A+T偏倚性;6个群体的群体内和群体间的遗传距离分别为0.003~0.284(12S rRNA),0.009~0.059(ND3)和0.004~1.062(12S rRNA),0.008~0.143(ND3);12S rRNA基因的51个单倍型和ND3基因的42个单倍型序列总的单倍型多样性(Hd)、核苷酸多样性(Pi)及核苷酸平均差异数(K)分别为0.972和0.937、0.035和0.079、31.414和27.176,均显示出丰富的遗传多样性。结合从GenBank中下载的12S rRNA和ND3基因同源序列的[鱼丕]科9属10种鱼类进行系统发育树的构建,结果表明巨[鱼丕]独自汇聚成一大单系群,怒江潞江坝群体、怒江三江口群体及澜沧江临沧群体间关系较近,澜沧江景洪群体可单独构成一个单系种群,红河河口群体、红河曼耗群体与其它巨[鱼丕]构成一单系种群后再同澜沧江景洪群体汇聚成一支。     

鱼类特有的Ring型E3泛素连接酶MARCH5A基因在刺激隐核虫感染下的表达分析

为探究大黄鱼MARCH5A的免疫作用,实验采用反转录PCR确认了该基因的c DNA序列。该序列全长1045 bp,包含1个长度为867 bp的开放阅读框,编码288个氨基酸;序列分析显示该蛋白含1个RINGv和4个跨膜结构域。进化树分析表明大黄鱼有11个MARCH家族蛋白(与哺乳动物相同),但鱼类存在多个亚型,MARCH5A为鱼类特有蛋白,其蛋白理化性质和三维结构均与MARCH5B存在一定的差异。荧光定量PCR分析显示,MARCH5A在健康大黄鱼的多个组织中均有表达,在血液和心脏中表达量最高,其次为鳃和脑,而在肾脏和皮肤中表达量最少。刺激隐核虫感染大黄鱼后,MARCH5A在皮肤中早期表达量显著上调,第2天为对照组的9.65倍,后期下调。在鳃、脾脏和头肾中的前期表达量也有所增加,后期下降。结果表明大黄鱼MARCH5A在抗刺激隐核虫免疫应答过程中可能发挥重要作用。     

The pigmenting effect of different carotenoids on fancy carp (Cyprinus carpio)

The optimal concentration of a panel of individual and combined carotenoid sources on skin pigmentation in fancy carp was investigated by nine experimental diets that were formulated and supplemented with astaxanthin at 25 mg kg^?1, lutein at 25 and 50 mg kg^?1, β‐carotene at 25, 50 and 75 mg kg^?1, and lutein combined with β‐carotene at 25 : 25 and 50 : 50 mg kg^?1, while a diet without supplemented carotenoid served as a control. The results showed that serum TC of fish fed diets containing supplemented with lutein plus β‐carotene at 25 : 25; 50 : 50 mg kg^?1 and lutein 50 mg kg^?1 diet were higher than the other treatments (P ≤ 0.05). Serum TC of the respective treatments was 6.2 ± 2.0, 7.8 ± 3.3 and 7.3 ± 1.9 μg mL^?1 serum, respectively. Fish fed diets combined with lutein and β‐carotene at 25 : 25, 50 : 50 mg kg^?1 and lutein 50 mg kg^?1 diet had serum astaxanthin concentrations similar to fish fed the diet with astaxanthin alone at 25 mg kg^?1. Serum astaxanthin concentrations was 0.7 ± 0.01, 0.9 ± 0.01, 0.4 ± 0.02 and 1.7 ± 0.18 μg mL^?1 serum, respectively. The chromaticity of fish body skin of red and white position was assessed by colourimetry using the CIE L*a*b (CIELAB) system. Pigmentation response of skin redness of fancy carp fed with diets combined with lutein and β‐carotene at 25 : 25, 50 : 50 mg kg^?1 and lutein 50 mg kg^?1 were higher than other treatments (P ≤ 0.05) but they were similar to fish fed with 25 mg kg^?1 astaxanthin diet. The redness (a* values) of fish fed diets with diets combined with lutein and β‐carotene at 25 : 25, 50 : 50 mg kg^?1 and lutein 50 mg kg^?1 were 28.3 ± 0.53, 29.9 ± 1.38, 28.8 ± 3.95 and 28.5 ± 2.49, respectively. After 3 weeks of feeding the experimental diets, the fish fed on a diet without carotenoid supplement for one week demonstrated that the same three groups still retained their redness and had an overall tendency to improve skin colouring. Finally, concentrations 50 mg kg^?1 of lutein, or the combination of lutein and β‐carotene at 25 : 25 mg kg^?1 showed the highest efficiency for improving skin pigmentation and redness of skin.     

Rapid seedlings regeneration from seeds and vegetative propagation with sucker and rhizome of Eremospatha macrocarpa (Mann & Wendl.) Wendl and Laccosperma secundiflorum (P. Beauv.) Kuntze

To develop efficient seedling production methods for Laccosperma secundiflorum and Eremospatha macrocarpa, a study was conducted to examine regeneration using offsets combined with several physical and chemical treatments of seeds. Offsets categorized into small, medium and large diameters, were planted in three conditions: shaded and open nursery, and greenhouse. We tested sucker from E. macrocarpa, and sucker and rhizome from L. secundiflorum. For both species, high viability percentage (ranging from 55% to 100%) were observed for small and medium suckers planted in shaded nursery and greenhouse, against less than 49% for sucker planted in open nursery. The mean seedling emergence times were estimated to 84, 77 and 75 days after planting (DAP) for small, medium and large sucker of L. secundiflorum, respectively under open nursery condition, and 76, 75, 95 DAP for small, medium and large suckers of the same species, respectively in shaded condition. Greenhouse has a significant positive effect on E. macrocarpa seedlings emergence time. For this species, the mean seedling emergence times were estimated to 43 DAP for small sucker and 76, 93 DAP for medium and large suckers. No seedling was obtained from rhizome planted in all the growing conditions tested. Concerning seed dormancy breaking, germination percentages and rates were determined for 13 treatments. The best treatments were pre-soaking unscarified seeds for 4 days in 1.01 g l⁻¹ and 0.10 g l⁻¹ KNO₃, with 79% and 68% of germination, respectively and in 3.46 × 10⁻³ g l⁻¹ GA₃ for 68% of germination. These methods are suggested to improve germination of L. secundiflorum seeds. Successful and recommended methods for E. macrocarpa are pre-soaking scarified seeds in 3.46 × 10⁻³ g l⁻¹ and 3.46 × 10⁻⁴ g l⁻¹ GA₃, 96% and 94% of germination, respectively. Dormancy, probably a combination of mechanical and chemical dormancy, is present in the two species.     

Regeneration of adventitious shoots from mature stored cotyledons of Japanese plum (Prunus salicina Lind1)

Adventitious shoot regeneration from mature stored cotyledons of Japanese plum (Prunus salicina Lind1) was achieved in vitro. The influences of the presence and absence of the light, different concentrations of thidiazuron (TDZ) and benzyladenine (BA) in the culture media, TDZ pretreatments and different basal salts on shoot regeneration were evaluated. TDZ was more effective in inducing shoot regeneration from mature stored cotyledons than BA. Dark incubation significantly increased the regeneration frequencies. Quoirin/Lepoivre (QL) basal salts stimulated shoot regeneration more than woody plant (WPM) or B5 salts did. The frequency of adventitious shoot formation varied among the varieties and the regeneration ability appeared to be genotype depended. The frequency of regeneration under the optimum tested conditions for ‘Bruce’, ‘Shiro’, ‘Redheart’, ‘Gladstone’ and ‘Early Golden’ cotyledons were 66.7%, 46.7%, 43.3%, 26.7% and 6.7%, respectively.     

Does root-sourced ABA play a role for regulation of stomata under drought in quinoa (Chenopodium quinoa Willd.)

The Andean seed crop quinoa (Chenopodium quinoa Willd.) is traditionally grown under drought and other adverse conditions that constrain crop production in the Andes, and it is regarded as having considerable tolerance to soil drying. The objective of this research was to study how chemical and hydraulic signalling from the root system controlled gas exchange in a drying soil in quinoa. It was observed that during soil drying, relative g_s and photosynthesis A_max (drought stressed/fully watered plants) equalled 1, until the fraction of transpirable soil water (FTSW) decreased to 0.82 ± 0.152 and 0.33 ± 0.061, respectively, at bud formation, indicating that photosynthesis was maintained after stomata closure. The relationship between relative g_s and relative A_max at bud formation was represented by a logarithmic function (r² = 0.79), which resulted in a photosynthetic water use efficiency WUE_Amax_/gs$\text{WU}{\text{E}}_{A_{\text{max}}/g_{\text{s}}}$ of 1 when FTSW > 0.8, and increased by 50% with soil drying to FTSW 0.7–0.4. Mild soil drying slightly increased ABA in the xylem. It is concluded that during soil drying, quinoa plants have a sensitive stomatal closure, by which the plants are able to maintain leaf water potential (ψ_l) and A_max, resulting in an increase of WUE. Root originated ABA plays a role in stomata performance during soil drying. ABA regulation seems to be one of the mechanisms utilised by quinoa when facing drought inducing decrease of turgor of stomata guard cells.     

Use of differently enriched rotifers,Brachionus plicatilis,during larviculture of haddock,Melanogrammus aeglefinus: effects on early growth,survival and body lipid composition

We evaluated the effects of enriched rotifers on growth, survival and on the lipid composition of haddock larvae. The treatments tested were (1) AlgaMac 2000^®, (2) AquaGrow^® Advantage and (3) Pavlova sp. paste and AlgaMac 2000^®. The treatments did not influence larval growth rate throughout the experimental period (P = 0.70). Larvae from all treatments grew approximately 8% of their dry weight per day between 1 and 29 days post hatch (dph). Treatment 3 resulted in the best survival, estimated to be 3 on a scale from 0 to 5, whereas for the two other groups the survival estimates were 0 and 2. Rotifers from treatment 1 had low sterol concentrations, high eicosapentaenoic acid/arachidonic acid ratio and their feeding resulted in high larval mortality. Rotifers enriched with Pavlova sp. had the lowest proportions of the sum of saturated fatty acids, docosahexaenoic acid and sum of ω3 and the highest proportions of the sum of monounsaturated fatty acids (ΣMUFA). This was partially reflected in larvae from treatment 3 in that they had the highest proportions of ΣMUFA and the lowest proportions of Σω3 (P < 0.0001 for both analyses). In addition, these larvae had the highest and lowest ΣC₂₀ and ΣC₂₂ polyunsaturated fatty acids (PUFA) respectively (P < 0.0001 for both analyses). We suggest that more research with ω3 and ω6 PUFA can lead to improvements in the rearing of haddock larvae produced in hatcheries.     

香蕉果实的1个14-3-3蛋白同源基因的克隆及序列分析(简报)

根据在香蕉果实抑制缩减文库中获得的1个14-3-3蛋白基因片段,采用PCR和RACE相结合的方法从香蕉(Musa acuminate L.AAA group cv.Brazilian)cDNA文库中筛选到其全长cDNA序列.序列测定和Blastx比对分析结果表明,该cDNA全长1 037 bp,含有1个完整的阅读框,其编码区编码261个氨基酸残基,具有植物14-3-3蛋白基因的保守结构域,并与其他植物来源的14-3-3蛋白具有很高的同源性,将其命名为Ma-14-3-36(Musa acuminate 14-3-3).采用遗传进化系统发育树的分析结果表明,Ma-14-3-36与来源于单子叶植物的多数14-3-3蛋白基因序列在同一个进化枝上.采用RT-PCR对其在香蕉果实发育不同时期的表达进行分析结果表明,在香蕉果实发育的不同时期差异表达,推测其可能在果实的发育中起作用.     

优良食味新品种苏香粳3号栽培特性和成香机理研究

[目的]了解苏香粳3号的栽培特性和成香机理.[方法]研究了苏香粳3号的栽培特性,利用特异引物检测了其香味的基因型,并利用全二维时间质谱(GC×GC-TOFMS)分析了致香物组分.[结果]苏香粳3号播种量为90.0 kg/hm2、施氮量为225.0 kg/hm2时采取直播栽培产量最高;苏香粳3号的抗、耐高温逆境的能力较好,并且较适宜网室栽培.香味基因检测结果表明苏香粳3号受fgr基因控制,第2外显子存在7 bp的碱基缺失.利用全二维时间质谱分析获得了香稻特征化合物2-乙酰基吡咯啉含量为0.021 5 mg/kg和初步的致香物组分.[结论]为苏香粳3号的推广应用提供了参考.     

基于轮廓投影的盆栽水稻三维重建方法研究

近几年,基于图像的高通量水稻表型研究取得了极大进展,但从三维层面进行研究的工作则相对较少。一般而言,相对于二维图像,从三维模型中能提取更为全面的性状参数。三维模型重建是作物三维表型研究的基础,提出一种适用于盆栽水稻三维点云的重建方法。该方法在相机固定、样本旋转的拍摄模式下获取水稻多视角图像,根据相机标定参数以及水稻轮廓二值图,通过轮廓投影方法重建水稻三维可视外壳点云模型,并通过反投影方法进行点云着色。结果表明,该方法对于不同时期及不同品种的水稻样本均能取得较好重建效果。