裙带菜3n、4n孢子体的人工育苗和海区栽培

使用室内保存培养的裙带菜2n♀♂配子体自交及与正常n♀♂配子体杂交，培育出裙带菜2n♀×n♂、n♀×2n♂两个组合3n幼孢子体和2n♀×2n♂组合的4n幼孢子体。经过40 d海区暂养后测定，3n幼孢子体两个组合平均长度分别为1.2 cm和1.1 cm，大于对照组合2n幼孢子体的0.9 cm和4n幼孢子体组合的0.7 cm。使用从短滨螺中提取的粗酶和R10纤维素酶的混合酶液将2n、3n幼孢子体酶解为原生质团，经Giemsa染色后观察到的染色体数分别为2n＝60，3n＝90。分苗后的海区栽培期间，在藻体的长度和重量方面，2n♀×n♂、n♀×2n♂两个3n孢子体组合间差异不显著(P>0.05)，与对照组合2n孢子体之间的差异极显著(P<0.01)。在裙带菜进入繁殖期的5月上中旬，3n孢子体仍保持较快的生长速度，在5月20日测定两个组合的藻体长度和重量分别达到4.2 m、2.3 kg和4.0 m、2.2 kg，而对照组合2n孢子体仅达到2.3 m和1.3 kg。4n孢子体生长明显地慢于对照的2n孢子体(P<0.01)，藻体生长最大值的时间为3月中旬，最大藻体长度和重量仅为1.6 m和1.1 kg。 试验结果表明，3n孢子体不发育，在繁殖期内无孢子叶形成，表现出不育的特性；4n孢子体形成孢子叶，但孢子叶很薄，孢子囊形成的数量少，发育水平也很低，经阴干刺激仅有极少量的孢子放出，显示出低育的特性。图2表1参15     

裙带菜孤雌生殖幼孢子体体细胞诱导2n♀配子体

以实验室内保存培养的裙带菜(Undaria pinnatifida)2n♀配子体为实验材料,经切碎培养,促进2n♀配子体成熟,排出卵进行孤雌生殖,形成幼抱子体.将0.5～1.0 cm的孤雌生殖幼孢子体的假根切除,从其体细胞中诱导出2n♀配子体.实验结果表明,在10～20℃范围内,培养20 d后,在15℃和20℃下的2n♀配子体排出的卵的孤雌生殖率分别为8.4%和7.4%,明显高于10℃下的1%0 20℃下诱导培养15d后就出现了2n♀配子体,培养60 d后,2n♀配子体的诱导率达到100%;15℃下培养30 d后才出现2n♀配子体,60 d后的诱导率为38%;而10℃下诱导培养45d后才开始出现2n♀配子体,60 d后的诱导率仅为12%.将诱导产生的2n♀配子体切碎,在20℃下培养10d后的成熟率为34%,60 d的成熟率达到100%.通过孤雌生殖幼孢子体诱导产生的2n♀配子体与正常♂配子体杂交形成了3n裙带菜幼孢子体.本研究发现了获得大量2n♀配子体的新方法,旨在为裙带菜三倍体幼苗规模化培育奠定基础.     

辽东半岛裙带菜室内常温全人工育苗：双高光控制、温度变化和配子体发育

2010年,作者在辽东半岛成功进行了裙带菜室内常温全人工育苗大规模生产试验,并全程进行了光照强度、温度和配子体发育相关性的研究。研究表明,采用双高光期(≥50μmolphotons/m2·s)调控配子体的生长和发育可达到理想效果。从采苗至度夏前,采用高光照使配子体充分完成营养生长;从度夏结束至幼苗出库前,同样采用高光照,使配子体快速发育形成孢子体并迅速生长。现场观察表明,只要光照强度逾越了诱导发育的阈值,裙带菜配子体在24℃仍然能够正常发育并形成孢子体;幼孢子体能够耐受24～26℃的高温,但是最适生长温度为20～22℃;孢子体越小,耐受高温能力越强。在24～26℃的高温条件下,幼孢子体生长缓慢,较大个体会出现尖端溃烂缺失的现象。在整个育苗过程中,根据温度变化和配子体的显微观察结果因地制宜地对光线进行实时调整。出库前培育的苗帘在幼苗密度、大小和健康方面均达到商业化栽培的要求。     

光照强度对巨藻幼孢子体生长的影响

在巨藻(Macrocystis pyrifera)的生活史中,配子体阶段的时间很短,如条件适宜只在几周内度过,而孢子体阶段是巨藻生命中最长的阶段,可达4～8年。在育苗过程中(2～3个月),幼孢子体的培养,约占育苗期的3/4。要获得个体较大的优质幼苗,掌握巨藻幼孢子体生长的适宜条件是非常重要的。由于巨藻的经济价值较高,国外对巨藻的研究较早,但到60年代才陆续进行培养幼体的研究。1978年巨藻配子体自墨西哥引进我国后,短期内发育为孢子体。     

光照时间与巨藻配子体和幼孢子体生长关系的研究

巨藻 Macrocystis pyrifera 配子体实验是在光强3,000勒下进行,以每日光照时间分为4、8、10、14、18和24小时等6组,孢子体实验以光照强度分为500、2,000、3,000勒3组。水温均为10～12℃。所得结果: 1.在光强3,000勒下,光照时间对巨藻胚孢子萌发和配子体形成的影响不大,每日光照8～14小时是雌配子体生长的适宜光照时间,雄配子体为8～24小时。每日光照8～14小时是巨藻配子体发育的适宜光照时间,每日光照10小时为最佳光照。雄配子体发育的适宜光时为每日光照8～24小时。2.巨藻幼孢子体所需要的光照时间,随光强的减弱而相应地延长。幼孢子体生长在3,000勒下,以每口光照8～12小时为宜,10小时为最适光照。在2,000勒下,每日光照略短于16小时为宜。500勒下,以光照20小时为最适光照。过短的光照限制了幼体的生长,光照过长引起严重白化死亡。3.首次发现巨藻幼孢子体在光强500勒每日光照20小时下,其长宽生长速度大大超过生长在光强3,000勒,每日光照10小时的藻体。据此认为,对巨藻幼孢子体培养的光照强度和光照时间,选用低光强长光照为宜,以500勒每日光照20小时最好。     

4-碘苯氧乙酸在海带夏苗培育中的应用

本文报道了4-碘苯氧乙酸(4-IPOAA)在海带夏苗培育中应用的试验结果。4-IPOAA对海带配子体和幼孢子体的生长发育有着明显的影响，高剂量的4-IPOAA(500mg／L)对配子体的发育有明显的抑制作用；解除4-IPOAA对配子体的抑制，配子体在短期内即能正常排卵、排精并受精形成孢子体；低浓度的4-IPOAA（25mg／L以下)能促进幼孢子体的生长。这项试验结果表明，有可能利用4-IPOAA对配子体的抑制特性，来改进目前所采用的低温、自然光条件下培育海带夏苗的工艺。作者建议把海带夏苗培育工艺改为以下步骤：(1)在常温下采苗；(2)在18℃以下水温条件下培育配子体；(3)在配子体成熟前用4-IPOAA处理，使其停止发育，在较高水温(20℃左右)条件下静水培养被抑制的配子体；(4)在计划夏苗出库前40—50天，解除4-IPOAA对配子体的抑制，恢复最适条件下流水培育；(5)肉眼见苗后及时下海暂养。     

关于海带染色体的数目

海带是一种具有明显世代交替的两年生褐藻，它的生活史有无性世代的孢子体和有性世代的配子体两个阶段。孢子体世代的核相是2n，配子体世代的核相是n。在孢子体和配子体的世代交替过程中，伴随着发生核相的交替。     

海带配子体克隆二次附苗技术

本研究主要从生产应用角度出发,在配子体克隆一次附苗的基础上进行二次附苗实验,系统探讨了海带配子体克隆二次附苗、育苗各环节的关键技术,结果显示1.25g/帘为最佳附苗密度;当幼孢子体普遍达到0.3~0.5mm时为最适宜起始洗刷时间,0.05MPa的压力为最佳起始洗刷压力;沉降式附苗法为最适宜附苗法;细胞最优过滤孔径为38μm。配子体克隆二次附苗幼苗发育速度快于孢子体附苗和克隆一次附苗,从而可大大节约生产成本。     

孔石莼的同形世代交替

通过实验室培养和显微观察,描述了孔石莼同形世代交替各个阶段的发育情况。雌雄异体的配子体成熟后,放散两鞭毛的配子,雌雄配子接合成合子进而发育成孢子体,孢子体成熟后放散四鞭毛的游孢子,游孢子固着后,可直接发育成配子体。其同形世代交替是单倍体的配子体与二倍体的孢子体相互交替。     

温度与裙带菜育苗的关系

本文就育苗期的裙带菜各阶段对温度的要求进行了较详细的论述。配子体的形成、生长、发育,孢子体的形成、生长等各阶段对温度的反应不一。配子体形成的最适温度为15～24℃,发育的最适范围为20～24℃。孢子体形成的最适温度为15～21℃,生长的最适温度为14～18℃。     

Physiological differences between gametophytes and sporophytes of five cultivar strains of Saccharina japonica

The demand for high‐yield cultivars of Saccharina japonica in farming areas calls for a practical and simple method to select desired parental plants for seed breeding. In this study, we evaluated PSII photosynthetic performance by measuring chlorophyll fluorescence and the nutrient uptake rate in both the micro‐gametophyte and macro‐young‐sporophyte in five native strains (S1, S2, S3, S4 and S5) of S. japonica with different morphological characteristics. We found significant differences in PSII photosynthetic parameters and nitrate uptake rates between the strains studied in both gametophytes and young sporophytes. Female gametophytes of all strains presented larger cell sizes than males (P < 0.05). Among all tested strains, S2 presented the largest cell sizes and highest levels of PSII photosynthetic parameters and nutrient uptake rates in female gametophytes and young sporophytes. In open sea cultivation, S2 presented the greatest width and largest fresh weight values but the lowest thickness among all strains studied. Correlation analysis further indicated that the algal fresh weight showed strong positive relationships with cell size (R² > 0.747), the PSII photosynthetic parameters of female gametophytes (R² > 0.689) and the nitrate uptake rate of young sporophytes (R² = 0.640). These findings are considered promising for the future seed breeding of renewable, high‐yield strains.     

GeO2对海带幼孢子体培育过程中硅藻污染的抑制效应

采用叶绿素荧光技术,以光系统Ⅱ最大荧光产量(Fv/Fm)为指标,结合形态显微观察,研究了GeO2在海带幼孢子体培育过程中菱形藻污染的抑制效应。结果表明,1)对于菱形藻,当GeO2浓度在5mg/L以上时,对其Fv/Fm值有显著影响,达到或超过15mg/L时菱形藻趋于死亡。2)对于海带幼孢子体,GeO2浓度在20mg/L以上时,对其Fv/Fm值有显著影响,达到或超过30mg/L时其趋于死亡。3)对于受到菱形藻污染的海带幼孢子体,GeO2浓度在15mg/L以上时对其Fv/Fm值有显著影响,达到或超过20mg/L时其趋于死亡。综合来看,当GeO2浓度为5～15mg/L时,菱形藻光合作用受到较强的抑制,而对海带幼孢子体影响不大。     

Morphological Traits of Wild and Selected Strains of Cultured Undaria pinnatifida from Galicia (NW Spain)

Wakame, Undaria pinnatifida, is one of the most popular seaweeds used for human consumption in the world. Wakame quality is mainly valued on the basis of its morphological features. Continual inbreeding and directional selection have traditionally been used with economic seaweeds to obtain elite strains with high‐quality forms. In this study, we compared the morphological traits of cultured sporophytes originating from wild and selected strains of U. pinnatifida in Galicia (NW Spain). Seedlings (young sporophytes) of the two strains were cultured at a sheltered site in a coastal bay of Galicia under the same environmental conditions. Sixteen different morphological measurements were taken on cultured sporophytes. We found that the sporophytes of both wild and selected strains were significantly similar in all studied morphological characters. These results suggest that the morphology of cultured strains of U. pinnatifida from Galicia is due to environmental conditions and that specific morphological traits are dependent on the cultivation environment. Consequently, the morphological traits of Galician U. pinnatifida populations are not an important factor in selective breeding for enhanced wakame quality, and hence, for the establishment of a germplasm bank (e.g., gametophyte stocks).     

Cu2+对鼠尾藻幼孢子体生长的影响

以鼠尾藻Sargassumthunbergii幼孢子体为材料,研究了Cu2+对不同生长时期的鼠尾藻幼孢子体生长的影响。不同生长时期的鼠尾藻幼孢子体对微量Cu2+都是敏感的。对于早期的鼠尾藻幼孢子体,5μg/L以上浓度的Cu2+对其正常生长不利;当Cu2+浓度达到或超过250μg/L时,该时期幼孢子体基本停止生长。对于后期的鼠尾藻幼孢子体,10μg/L以上浓度的Cu2+对其正常生长不利;1μg/L浓度的Cu2+对其生长有促进作用;当Cu2+浓度达到或超过50μg/L时,该时期幼孢子体增长缓慢或基本停止生长。鼠尾藻幼孢子体的假根由于结构和功能特性,对Cu2+的敏感程度不大,Cu2+处理初期依然表现出快速增长。     

铁盐对海带雌配子体生长发育的影响

为探明铁盐对不同品种(系)以及相同品种(系)在不同生长条件下海带雌配子体的影响,通过添加不同质量浓度的Fe3+,对培养在低温弱光[(10.0±1.0)℃、2μmol/(m2·s),L]和高温强光[(15.0±1.0)℃、80μmol/(m2·s),H]条件下的"901"、韩国海带和"连杂1号"3个品种(系)海带雌配子体...     

Dietary value of gametophytes and juvenile sporophytes of the brown macroalga <Emphasis Type="Italic">Eisenia bicyclis</Emphasis> for juvenile abalone <Emphasis Type="Italic">Haliotis diversicolor</Emphasis>

The dietary value of juvenile stages (gametophyte and juvenile sporophyte) of the brown macroalga Eisenia bicyclis for post-larval and juvenile abalone Haliotis diversicolor of 2.0–6.5 mm in shell length (SL) was examined and compared with that of a benthic diatom, Nitzschia sp., in laboratory experiments. Most abalone actively fed on these diets, but there were large variations in the growth rate among the diets and among the growth stages of abalone. Growth rates of abalone fed on Nitzschia sp. were highly variable within each growth stage, but showed no clear differences among growth stages. In contrast, in abalone fed gametophytes or juvenile sporophytes, growth rates linearly increased as abalone grew. Growth rates of >60 μm SL/day were observed in juveniles of >3 mm SL fed gametophytes, and juveniles of >5 mm SL fed juvenile sporophytes. These results indicate that the dietary value of the juvenile stages of E. bicyclis for the abalone changes as they grow, and with growth juvenile abalone begin to efficiently utilize gametophytes and juvenile sporophytes in that order.     

Variation in morphology and PSII photosynthetic characteristics of Macrocystis pyrifera during development from gametophyte to juvenile sporophyte

Currently, there is increasing demand for brown kelp, especially Macrocystis spp., to support the development of the abalone industry and for use as raw material for the production of alginate. Thus, there is a need to supplement the naturally available kelp biomass with the development of mariculture techniques. In this study, we investigated whether it was possible to cultivate Macrocystis pyrifera sporophytes in the laboratory using gametophyte clones. We propagated gametophytes by periodic fragmentation and then mixed aseptically an equal number of male and female gametophytes to induce fertilization. Approximately 60 days after fertilization, numerous embryonic sporophytes emerged on the seed fibre. By using chlorophyll fluorescence technology, we investigated variation in the photosystem II (PSII) characteristics of M. pyrifera during development from the gametophyte to juvenile sporophyte stage. During this growth period, both the optimal (F_v/F_m) and effective (YII) PSII quantum yields increased significantly from the haploid gametophyte to diploid sporophyte stages. In addition, by comparing female gametophytes with male gametophytes, we found that female gametophytes were not only larger and more pigmented than the males, but also recorded higher values of F_v/F_m and YII. Our results supplemented information on the life cycle and PSII photosynthetic performance during the early development and confirmed the possibility of artificial seeding technology, both of which may contribute to mariculture of M. pyrifera in China in the near future.     

海带染色体的DAPI染色及核型初步分析

鉴于海带染色体比较小且数目存在分歧等原因,利用0.2%秋水仙素对海带配子体及孢子体处理10 h左右,经过卡诺试剂固定、多种酶组合处理及30 cm的高位滴片,可以获得质量比较高的海带染色体;使用灵敏度高、特异性强的DNA荧光染料DAPI进行染色,结果显示,海带雌、雄配子体的染色体各为31条,孢子体染色体为62条,大多为短杆状或者点状;雌配子体染色体的大小为0.78～2.61μm,稍大于雄配子体(大小为0.57～2.17μm)。根据染色体的大小,对海带配子体的染色体核型进行了初步分析。这些结果为分子标记的染色体定位等细胞学研究奠定了技术基础。     

不同光质及胁迫处理对鼠尾藻及附生藻类光合生理的影响

利用鼠尾藻(Sargassun thumbergii)、菱形藻(Nitzschia)、石莼(Ulue pertusa)和绢丝藻(Callithamnion corymbosum)作为研究对象,通过白光、蓝光、红光照射,1%硝酸铵、1%柠檬酸、3%硫酸铵处理不同时间,淡水浸泡不同时间3种杂藻清除方法,系统研究光质、药物和淡水处理对鼠尾藻及杂藻光合生理的影响。结果显示,对于相对生长速率(RGR)、表观光合速率(Pn)及表观光合速率与呼吸耗氧速率(R)的比(Pn/R),鼠尾藻幼孢子体在蓝光下均明显大于在白光和红光下,而菱形藻则在红光下较大,且鼠尾藻幼孢子体与菱形藻在蓝光下的Pn比明显大于其在白光和红光下的Pn比。结果显示,鼠尾藻幼孢子体若与菱形藻进行竞争,在蓝光下相对于在白光和红光下更有优势。硝酸铵、硫酸铵、柠檬酸药物处理对鼠尾藻幼孢子体的生理状态有一定的影响,且这种伤害具有不可逆性;对鼠尾藻嫩芽的伤害较小,且可恢复正常;对石莼的清除效果不明显,对绢丝藻有伤害。淡水处理对鼠尾藻幼孢子体有伤害,对鼠尾藻嫩芽伤害较小,对石莼影响不大,对绢丝藻有伤害。研究表明,在鼠尾藻幼苗早期培育过程中,可增大蓝光的照射或减少红光的照射,在一定程度上能促进鼠尾藻的生长且抑制菱形藻的生长;在鼠尾藻早期幼苗的杂藻清除中,应避免使用1%硝酸铵、1%柠檬酸和3%硫酸铵处理,会对鼠尾藻幼孢子体产生伤害;鼠尾藻育苗早期不宜使用淡水浸泡除去杂藻,鼠尾藻嫩芽每次淡水浸泡30 min,可清除杂藻,且对藻体无伤害。