岷江眉山段四川华鳊年龄与生长

为了解我国长江上游特有鱼类四川华鳊Sinibrama taeniatus种群资源现状,于2013年3月至2014年1月在长江一级支流岷江眉山段采集了580尾四川华鳊样本,以鳞片作为鉴定材料,对其年龄和生长特征进行了研究。结果显示:四川华鳊鳞片年轮特征明显,表现为普通疏密型,为一年一个周期。研究样品的年龄由0~+~3~+(1~4龄)4个年龄组组成,其中以1~+~2~+龄(2~3龄)为主,占样品总量的96.07%。体长(L,m)和鳞径(R,mm)具有显著相关性雌、雄鱼差异无统计学意义(P0.05)表达式为L=25.45R+65.73。体质量(W,g)与体长呈幂函数相关,雌、雄鱼差异无统计学意义(P0.05),属等速增长,表达式为W=2.4×10~(-5)L~(2.94)(R~2=0.25)。Von Bertalanffy生长方程分别为:L_t=139.57×[1-e~(-0.15(t+3.16))],W_t=47.97×[1-e~(-0.15(t+3.16))]~(2.94),生长系数为0.15,拐点年龄为4.09龄,对应的体长和体质量分别为L_i=92.06mm,W_i=14.13g。岷江眉山段四川华鳊属于生长相对较快型鱼类。建议依法取缔非法捕捞工具,减少水电工程建设,这些措施对于保护四川华鳊种质资源有重要作用。     

我国华鳊属鱼类形态差异及其物种有效性的研究

为探讨华鳊属鱼类种间和种内居群间的形态差异及其物种有效性,采用多变量形态度量,结合传统分类方法,获得该属鱼类不同地理居群共224尾标本的32个测量性状和7个可数性状数据,并做主成分分析。在可数性状上,海南华鳊各居群间无差异,但明显不同于其他种类;四川华鳊与大眼华鳊差别明显,与伍氏华鳊之间也存在较大程度的差异;大眼华鳊的乌江和珠江居群之间存在显著差异,而伍氏华鳊各地理居群差异不明显。在可量性状上,四川华鳊和大眼华鳊的乌江居群都明显区别于其他种或居群,而大眼华鳊的珠江居群与伍氏华鳊之间以及海南华鳊各居群之间没有明显差异。对上述结果分析认为：四川华鳊和海南华鳊为两个有效的物种;大眼华鳊的乌江标本是一个未被描述的物种,而珠江居群和伍氏华鳊各居群应属同一个种。     

大眼华鳊和伍氏华鳊的形态差异及其物种有效性

分别对大眼华鳊和伍氏华鳊 137尾标本 7个可数性状和 18个可量性状进行主成分分析 ,以探讨这两个种之间的形态差异及其物种有效性。研究结果显示 :无论是在可数性状上还是可量性状上 ,大眼华鳊和伍氏华鳊之间的形态差异并不显著 ,而且大眼华鳊大陆的标本和台湾的标本无明显的不同。此表明 ,大眼华鳊和伍氏华鳊应该为同一个种。根据国际动物命名法规 ,伍氏华鳊应是大眼华鳊的次定同物异名。     

青菱湖中长春鳊生物学的研究

1983-1985年对通长江的青菱湖中长春鳊的年龄与生长、食性、繁殖及其鱼群江湖交流等生态习性进行了调查。发现相当部分标本的鳞片上有明显的幼轮标志;性成熟后,雌鱼的生长较雄鱼迅速;摄取的食物种类与湖中各种水生植物的季节性盛衰相适应,但有一定的选择性;亲鱼能在湖中成熟产卵,但鱼卵因受自然条件限制,不能发育成活。湖中鱼群的补充仍依靠数量不定的1龄幼鱼由长江干流逆水或顺水伺机窜入湖内。江湖之间闸门的启闭主要根据农田水利的需要,因此,长春鳊鱼群规律性的江湖交流仍然受到阻碍。       

长江下游鳊种群生长及繁殖特性

为了解长江下游鳊种群生长特征和繁殖特性,于2017-2018年连续4个季度在长江下游铜陵、芜湖、当涂、镇江、靖江、南通江段共采集鳊样本1040尾.采样群体体长为84.79～305.00 mm,体质量为8.50～673.39 g,雌雄比例为1 ∶ 0.97.样本年龄为1～6龄,其中2～3龄为优势年龄组,占比为87.79％...     

七子花的繁殖生物学研究

对国家2级保护植物七子花（Heptacodium miconioides)的开花、传粉与结实等繁殖特性进行了研究。结果显示：七子花的花无梗,由多轮紧缩呈头状的聚伞花序组成顶生圆锥花序,多数花序开两轮花（基轮和中轮）,少数只开基轮花。自花传粉的比例高,花后4h的柱头花粉多超过60粒,8h的柱头可多达142粒,其中近1／3的花粉萌发,少数能到达子房。每个子房仅1枚胚珠可育,其平均结实率为40．6％,上轮花的开花会影响下轮花的结实率,降低幅度可达34．8％,早开花的结实也会影响迟开花的结实。表明七子花的结实率很低,资源限制是影响结实的主要因素。     

赤眼鳟的繁殖生物学

对赤眼鳟(Squaliobarbus curriculus)的性腺发育、性征、繁殖力、性比、繁殖习性、胚胎发育和胚后发育进行了研究。赤眼鳟初次性成熟年龄为2冬龄。繁殖季节为4月下旬至8月上旬,以5~7月为盛产期。网箱饲养已达性成熟年龄的赤眼鳟性腺成熟系数大于池养及江河野生的。其相对繁殖力为252.8粒/g,高于池养者31.05%,高于野生鱼28.0%。雄鱼体形比雌鱼长,成熟雄鱼在繁殖季节胸鳍具有颗粒状珠星,非繁殖季节珠星消失。雌雄比接近1∶1。赤眼鳟属敞水性产卵类型,为不分批产卵鱼类。广西江河的赤眼鳟天然产卵场有11处,主要分布于郁江,左江和右江各有1处。在水温28~28.5℃的情况下,自受精到孵化所需时间为16 h 10 min,积温453℃.h。鱼苗经17 d发育,鳞片完全,体形、习性与成鱼相似。     

黄鳝繁殖生物学的观察

根据黄鳝Monopterus albus的解剖及调查资料,就繁殖生物学方面作了阐述。     

岷江百合组织培养和快速繁殖(简报)

以岷江百合新鳞茎为材料,MS NAA 0.05mg/L(单位下同) 6-BA 2.0为不定芽诱导培养基,MS NAA 0.5 6-BA 2.0 GA 2.0为增殖培养基进行培养,30d为一个继代周期,繁殖系数4～5。在1/2MS IBA 0.5 活性炭1g/L培养基上进行生根培养。移栽到腐叶土:木屑:泥塘土为1:1:1混合基质中,成活率达85%。     

沱江宽体华鳅繁殖特性

对2010年4~11月采集于沱江资中段的573尾宽体华鳅（Sinibotia reevesae）进行了繁殖特性研究。结果表明：宽体华鳅性腺发育分为6期,5月卵巢发育到Ⅳ期,精巢发育到Ⅴ期。繁殖期在5~8月,盛期为6~7月,可通过胸鳍和生殖孔差异辨别性别。繁殖群体雌雄性比为1︰1.15,2~3龄性成熟,性成熟最小年龄两性均为2龄,为补充群体占优势的繁殖群体。雄性（Ⅴ期）最小性成熟个体体长71 mm,体重5.43 g,成熟系数4.76%,雌性（Ⅲ期）最小性成熟个体体长76 mm,体重7.80 g,成熟系数1.46%。成熟卵巢中卵子大小基本一致,卵径分布为单峰型,属于单次产卵类型;繁殖群体体长76~120 mm,体重7.80~41.60 g;卵小,沉性,野生条件下胚胎发育需要流速较快的流水环境。     

The reproductive biology of the genusBaldellia (Alismataceae)

The reproductive biology of the genusBaldellia was studied under cultivation and in nature.B. ranunculoides subsp.repens is self-incompatible whereasB. ranunculoides subsp.ranunculoides andB. alpestris are self-compatible. Bud-pollination occurs in theB. alpestris. Self-incompatibility correlates with the production of fewer, larger, more showy flowers, higher pollen production (but reduced pollen grain size), fewer carpels and smaller seeds. Resource allocation to sexual reproduction is inversely correlated with the degree of vegetative growth.B. ranunculoides subsp.repens produces more ramets than subsp.ranunculoides, which reproduces mainly by seeds.B. alpestris is intermediate between the two since it is self-compatible, produces fewer, larger seed than subsp.ranunculoides and is also able to propagate by vegetative means.     

Features of reproductive biology in females of bitterlings (Cyprinidae: Acheilognathinae) from the Amur River basin

Data on morphological and functional characteristics of the ovipositor, conical organ, and ovaries in four species of bitterlings (Russian bitterling Acanthorodeus asmussii, Khanka spiny bitterling A. chankaensis, bitterling Rhodeus sericeus, and Amur bitterling R. amurensis) from the Amur River basin are obtained and reviewed for the first time. In all studied fish species, several generations of sex cells develop at the same time, which leads to releasing of oocytes in batches. The specificity of Amur bitterling, bitterling, and Russian bitterling to selection of mollusks for egg deposition is determined.     

Structure and biology of nectaries in Tabebuia serratifolia Nichols (Bignoniaceae)

THOMAS, V. & DAVE, Y., 1992. Structure and biology of nectaries in Tabebuia serratifolia Nichols (Bignoniaceae) . Tabebuia has both floral and extrafloral nectaries, situated on the petiole, bract, calyx, around the ovary and on the pericarp. The floral nectary present around the ovary base is differentiated into epidermis, secretory zone and sub-secretory zone. It is supplied by phloem strands up to the secretory zone. A mature extrafloral nectary consists of a single large basal cell and a head comprising a layer of vertically arranged elongated cells. Starch, protein and lipid are present in the floral nectary. The major insect visitors to both types of nectaries are honey bees, houseflies and ants.     

The reproductive biology of Plagioscion squamosissimus (Heckel, 1840) in the Pará River estuary (Amazon Estuary)

This study describes the reproductive biology of the South American silver croaker Plagioscion squamosissimus (Heckel, 1840) in the Pará River estuary. Data were collected bimonthly from June 2007 to May 2008. In all, 334 specimens were examined. The gonads were processed with histological techniques, and the ovaries were subjected to morphometric analysis. The length at first maturity (L₅₀) values were 16.14 and 21.43 cm total length for females and males, respectively. The sex ratio based on the total number of individuals favoured the females (1.11 females: one male). Macroscopically, the gonads were classified as immature (A), maturing (B), mature (C) and spent (D). Microscopically, four germ cell types were distinguished based on the development of the ovaries. Chromatin nucleolus (I), perinucleolar (II), cortical alveoli (III) and full‐vitellogenic (IV) oocytes were observed in all ovarian stages, except that of the mature individuals which showed the largest number of full‐vitellogenic oocytes (IV), with a mean diameter of 565.4 μm (±147.4). Substantial percentages of individual P. squamosissimus were found to be in a reproductive condition. Reproductive activity was recorded throughout the year in the Pará River estuary, primarily in February/March and August/September.     

The reproductive biology of four African catfishes (Osteichthyes: Clariidae) in Anambra River basin,Nigeria

The reproductive biology of Clarias ebriensis, C. agboyiensis, C. macromystax and C. buthupogon was investigated over a period of 32 months in Anambra River basin, Nigeria. Immature (stage I) C. ebriensis and C. agboyiensis were recruited into the fishery in October, and in September in C. macromystax and C. buthupogon. The occurrence of mature (stage III) fish all the year round indicated the potential of the Clarias species to breed at any time of the year. C. ebriensis bred from April–September while breeding occurred from May–September in the other species. The clariids matured between their first and second year of life. C. ebriensis females matured earlier than males but the reserve was the case in C. agboyiensis, C. macromystax and C. buthupogon. Ovary weight was a better indicator of egg number than either total length or body weight in all species. Communal spawning is reported for the first time in Clarias species and its significance to survival discussed.     

Assessing reproductive biology of Macrobrachium lamarrei in the Ganges River (NW Bangladesh) in relation to environmental parameters

Macrobrachium lamarrei (H. Milne-Edwards, 1837) is a well-known freshwater prawn species of Bangladesh. The aim of the research is to explore various reproductive aspects (size at sexual maturity, reproductive period and fecundity) of M. lamarrei in the Ganges River, Bangladesh through October 2012 to September 2013. We also study the environmental parameters and their impact on reproduction of M. lamarrei. A total 391 (ovigerous = 141, non-ovigerous = 250) female specimens were collected using Drag net. The TL₅₀ (the TL at which 50% of individuals become mature) was calculated by a logistic equation as 5.20 cm. Based on the availability of ovigerous females the spawning season was February-November with the peak June-July. Further, 50% and 90% ovigerous females were observed when Fulton’s condition factor (K_F) was 0.85 and 1.03, respectively. The total fecundity (F_T) was ranged from 65 to 370 where TL was 4.20–6.40 cm and BW was 0.84–2.50 g. Fecundity was found to be highly correlated with TL (r² ≥ 0.96, r_s = 0.96, p < 0.0001) and BW (r² ≥ 0.88, r_s = 0.93, p < 0.0001). Temperature (r_p = 0.82, p = 0.009), dissolved oxygen (DO) (r_p = −0.83, p = 0.0007), pH (r_p = 0.80, p = 0.0014) and total alkalinity (r_p = −0.87, p = 0.0002), were highly correlated with ovigerous females. The average temperature on peak spawning season was 32 °C. Also, the spawning period connected with the peak rainfall and showed a notable relation between rainfall and ovigerous females. In addition, exploration of long data series pointed that yearly average air temperature is rising by 0.029 °C yr⁻¹, whereas yearly average rainfall is falling by 2.96 mm yr⁻¹. Therefore, the result will be helpful for the sustainable management and conservation of M. lamarrei through fixed permissible mesh size and establishment of a ban period in the Ganges River, Bangladesh and adjoining ecosystems.     

The reproductive biology of the two-banded sea bream (Diplodus vulgaris) from the southwest coast of Portugal

The study of the reproduction of Diplodus vulgaris (Geoff.) as part of a base‐line study of the fishery resources of the south‐west coast of Portugal, was based on the analysis of the spawning season, gonad maturation, size at maturity, fecundity and hermaphroditism. The spawning season is relatively long, from December to March, with peaks in January and February. No significant differences were found either in the sex ratio (M : F = 1.01) over the year or by size. The size at first maturity (L₅₀) for all sexes and undetermined individuals combined was 18.33 cm total length (TL), with no significant differences between males and females. The estimated L₅₀ is considerably greater than the minimum legal size in Portugal of 15.0 cm. Mean absolute fecundity (F_a) was 131 127 oocytes, ranging from 31 523 to 250 608. The relationship between absolute fecundity and total length (TL) (F_a = 25 398 TL – 484 426) and somatic weight (SW) (F_a = 878.8SW – 71 416) was of the linear type. The mean number of oocytes per gram of somatic weight was 526, ranging from 194 to 887. The reproductive strategy of this species is characterized by a rudimentary hermaphroditism with possible protandry, as evidenced by the existence of individuals in sexual transition.     

The reproductive biology of Common frog (Rana temporaria) populations from different altitudes in northern England

The study investigated the ecophysiological differences between populations of the Common frog( Rana temporaria L.) from different altitudes in northern England. Frog embryos in upland northern ponds experience very low temperatures during the period of embryonic development. These embryos were found to have a lower lethal limit for 50% normal development of2–8 °C, compared with3–8 °C for lowland embryos. These values are below most of the lower limiting temperature estimates previously obtained for R. temporaria . Embryos from upland ponds developed faster at low temperatures than embryos from lowland ponds. This may be an adaptation to the shorter growing season and lower temperatures at higher altitudes. Upland female frogs were found to be shorter and produced fewer eggs than lowland females. The differences found between lowland and upland frogs are discussed in terms of their potential adaptive significance.     

The reproductive biology of Parazoanthus parasiticus (Hexacorallia: Zoanthidea) in Bermuda

The zooxanthellate macrocnemic zoanthid Parazoanthus parasiticus lives at densities of 3–10 cm⁻² in the chimney sponge Callyspongia vaginalis in Bermuda. It is gonochoric and oviparous. Small oocytes appear in the mesenteries in February–March, grow slowly at first, then increase volume rapidly as seawater temperature passes 27 °C in July. In 1993, oocytes were found to have been shed over 2–3 days around the full moon on 1 September, with inferred small spawnings over the preceding and following full moons. Reproduction had finished by November. In 1999, spawning of azooxanthellate eggs ∼ 250 μm diameter took place on 28 August, two nights after full moon. Spawnings therefore precede those known for four oviparous scleractinians and one gorgonian in Bermudian waters by about a week. The eggs are not shed in bundles and lack zooxanthellae. The unknown embryonic development and larval type in macrocnemic zoanthids is discussed and remains to be resolved by further study with P. parasiticus. Contribution number 1662 from the Bermuda Biological Station for Research.