皱纹盘鲍的遗传育种与养殖技术研究

IOCAS-IR > 海洋环流与波动重点实验室

	皱纹盘鲍的遗传育种与养殖技术研究
其他题名	Studies on genetic breeding and cultivation techniques of Pacific abalone, Haliotis discus hannai Ino
	吴富村
学位类型	博士
	2008-06-16
学位授予单位	中国科学院海洋研究所
学位授予地点	海洋研究所
关键词	皱纹盘鲍遗传育种贝壳颜色食物贝壳形态生长存活遗传参数选育系杂交杂种优势配合力基因型环境互作养殖中间培育密度规格分选
摘要	优良的种质是产业发展的重要保证，品种更新和养殖技术的发展已经给世界农业带来了令人瞩目的成就，然而我国水产生物的育种工作刚处于起步阶段，而育种技术的研究则更是滞后。借鉴陆生生物中发展起来的相对成熟的研究方法，可以帮助加快海洋生物遗传育种相关研究的进度。本研究以我国北方海区重要的海洋经济动物－皱纹盘鲍为研究对象，从表型遗传、数量性状遗传等2个方面开展了皱纹盘鲍的遗传育种研究，同时从幼鲍培育密度与分选效应等方面研究了皱纹盘鲍的中间培育技术。主要结果如下： 1. 皱纹盘鲍的贝壳颜色遗传、食物对贝壳颜色表现型的影响，贝壳颜色与生长速度间的关系将贝壳颜色为橘红色（O表型）的突变型皱纹盘鲍与贝壳颜色为绿色（G表型）的野生型皱纹盘鲍进行了连续2代的交配实验。结果表明：皱纹盘鲍橘红色的贝壳颜色相对于绿色的贝壳颜色为隐性性状，皱纹盘鲍的贝壳颜色表型受单位点、2个等位基因遗传控制，其中基因型为oo的个体，贝壳颜色的表现型为橘红色（O表型），而基因型为GG或Go的个体，贝壳颜色的表现型为野生型（G表型）。为探讨食物类型对不同基因型皱纹盘鲍贝壳颜色表现型的影响，对不同贝壳颜色表型的个体投喂不同种类的食物，结果表明，除遗传因素外，皱纹盘鲍的贝壳颜色表现型显著地受食物类型的调控。其中oo基因型的个体，在摄食底栖硅藻（Navicula sp.）和红藻时，贝壳颜色的表型为橘红色；而在摄食褐藻、绿藻和以海带粉为唯一海藻源的人工配合饵料时，贝壳颜色的表型为黄色。GG和Go基因型的个体，在摄食底栖硅藻、红藻时，贝壳颜色的表型为褐红色；在摄食褐藻、绿藻和以海带粉为唯一海藻源的人工配合饵料时，贝壳颜色的表型为绿色。该结果表明，相同基因型的皱纹盘鲍在摄食不同类型的食物时，贝壳表现型不同，即不同类型的食物可以导致2种基因型皱纹盘鲍的贝壳颜色表现型在一定范围内发生转换：oo基因型的个体，贝壳的颜色可以表现为橘红色或者黄色，不会出现野生型皱纹盘鲍的褐红色或绿色；而GG与Go基因型的个体，相应的贝壳颜色表型只能是褐红色或者绿色，不会出现oo基因型可能表现的橘红色或黄色。特定基因型的皱纹盘鲍，在摄食特定类型的食物时贝壳的相应部位可表现出特定的颜色。皱纹盘鲍的这种“食物－贝壳颜色”的相关性可作为一种形态标记，用于标识皱纹盘鲍的个体和群体，该标记技术可用于皱纹盘鲍的养殖技术和遗传学研究。此外，选用了贝壳颜色遗传学实验中建立的贝壳颜色发生分离的家系为实验材料，以壳长为指标，分析比较了来自相同家系的O表型与G表型个体之间的生长速度。结果表明，在幼鲍发育至412天止的3-5个统计时段内，没有在同一家系来源的2种贝壳颜色表型个体之间检验到生长速度的显著差异。 2. 皱纹盘鲍不同选育群体及杂交群体的贝壳形态参数分析在皱纹盘鲍的7个群体中（包括已经对生长速度为指标进行了多代人工选育的群体4个、野生群体之间直接杂交繁育的杂交F1群体3个），测量了4-6龄成体样本的壳长（L）、壳宽（W）、壳高（H）和壳重（Sw），并计算了L/（L+W+H）、W/（L+W+H）、H/（L+W+H）和Sw/（L×W×H）等4个壳形态学参数。用方差分析方法（MANOVA、ANOVA）统计并比较了这些壳形态参数在皱纹盘鲍群体间的遗传变异。结果表明，4个壳形态参数在不同群体间变异系数分别为0.34、0.74、2.62和6.54，其中，H/（L+W+H）与Sw/（L×W×H）在各供试群体间均具有较高的多态性且差异达显著水平，表明这2个参数在不同群体间存在较高的遗传变异。由于在活体情况下无法测量壳重（Sw）性状，建议以参数H/（L+W+H）为指标对皱纹盘鲍贝壳形态（如壳型）等进行人工选择。 3. 皱纹盘鲍成体阶段生长性状的遗传参数估计采用巢式设计，分析了成体阶段不同发育期皱纹盘鲍的壳长与生长速率的遗传力、不同发育期的壳长性状之间的遗传相关、以及不同发育期的生长速率之间的遗传相关，结果表明：（1）壳长遗传力在受精后第70 、130、320、320、380、490与550天的雄性组分估计值分别为0.161 ± 0.075、0.312 ± 0.131、0.326 ± 0.331、0.135 ± 0.228、0.153 ± 0.185和0.180 ± 0.106；雌亲组分估计分别为0.312 ± 0.172、0.699 ± 0.168、0.695 ± 0.168、0.977 ± 0.407、0.427 ± 0.195和0.449 ± 0.027。（2）生长速率遗传力在受精后第320~380天、490 ~ 550天，雄、雌组分估计值分别为0.080 ± 0.120（雄）、 0.210 ± 0.191（雌）以及0.299 ± 0.146（雄）、0.306± 0.148（雌）。雌亲组分的壳长遗传力和生长速率遗传力估计值较大且均达显著水平，表明皱纹盘鲍在成体阶段依然受母性效应的影响。成体阶段生长性状遗传力水平的估计对制定科学的皱纹盘鲍育种方案有指导意义。（3）雄亲组分估计的不同发育期（第390 ~ 550天）壳长间遗传相关为0.597 ~ 1.000，雌亲组分估计为0.589 ~ 1.177。由雄亲、雌亲组分估计，受精后第320~380天与第490 ~ 550天两个发育阶段生长速率间遗传相关均接近于0。雌亲组分估计不同发育期壳长间遗传相关均达显著水平（t0.05, d.f.=13 = 4.33 ~ 11.69，P<0.01），表明壳长性状早期选择有效，即在皱纹盘鲍早期阶段依据壳长性状对个体进行择优或去劣可在后期阶段获得壳长较大的个体。由于使用的雄亲数目少（8个父系半同胞），实验中以雄亲组分估计的遗传参数误差较大。 4. 皱纹盘鲍选育系间的群体杂交进行了皱纹盘鲍4个人工选育系之间的完全双列杂交实验，以群体交配的方式共建立了16个组合；此外，以大连“98”选群与汕头“S”选群为亲本，以群体交配的方式建立了4个交配组合。对不同方向的杂交组合进行了中亲杂种优势、超亲杂种优势以及配合力等方面的评价。（1）测量了4个选育群体（R、97、S和J）及其各杂交组合在受精后第9、20和30天时的壳长，统计分析了不同选育系间壳长性状的差异、评价了不同方向杂交组合的中亲与超亲杂种优势、以及配合力。结果如下：选育系群体内交配繁育的4个组合，在受精后第9、20和30天的壳长均有显著差异，其中，97  97组合在早期发育各阶段均为最小，分别为0.462 ± 0.023mm、0.698 ± 0.057mm和1.476 ± 0.234mm；S  S组合的3次测量值均为最大，分别为0.522 ± 0.023mm、0.824 ± 0.084mm和1.798 ± 0.229mm。两个方向杂交组合与选育系亲本群体内交配组合的平均值和高亲值比较，得到如下结果：（A）受精后第9天壳长表现正向中亲杂种优势的组合有6个、表现负向中亲杂种优势的组合6个，其中J  97组合的中亲优势率最高，为9.05%；R  S组合最低，为-6.61%。正向高亲杂种优势组合有4个、负向高亲杂种优势组合有8个，其中S  J组合的高亲优势率最高，为5.77%；R  S组合最低，为-7.96%。（B）受精后第20天壳长表现正向中亲杂种优势的组合有7个、表现负向中亲杂种优势的组合5个，其中J  97组合的中亲优势率最高，为12.60%；J  R组合最低，为-8.72%。正向高亲杂种优势组合有3个、负向高亲杂种优势组合有11个，其中J  97组合的高亲优势率最高，为12.20%；J  R组合最低，为-12.67%。（C）受精后第30天壳长表现正向中亲杂种优势的组合有7个、负向中亲杂种优势的组合5个，其中97  S组合的中亲优势率最高，为24.08%；S  97组合最低，为-12.69%。正向高亲杂种优势组合有6个、负向高亲杂种优势组合有6个，其中97  S组合的高亲优势率最高，为15.95%；S  J组合最低，为-19.44%。上述结果表明，皱纹盘鲍不同选育系之间的交配组合，杂种优势率差异很大，因此，通过组配实验，将杂种优势率高的交配组合选择出来应用于生产，可望显著提高目标性状的产量。对早期发育阶段各生长期壳长性状，亲本一般配合力（GCA）、各杂交组合间特殊配合力（SCA）以及正反交（REC）效应值进行方差分析，结果表明：各亲本GCA差异显著，说明各选育群体存在显著的遗传差异，其中汕头选群“S”在测量的各个生长期均为正值且显著大于其它各亲本；特殊配合力（SCA）以及正反交（REC）效应值较大在各杂交组合间存在显著差异，说明在早期生长发育阶段非加性遗传效应（显性和上位效应）占主导地位。综合各个生长期亲本GCA和杂交组特殊配合力（SCA）以及正反交（REC）效应值，杂交组合97×S在早期生长阶段不仅有较高SCA值而且两个亲本也具有较大的GCA值，表明选育系97和S较适宜作为杂交亲本使用。（2）大连“98”选群与汕头“S”选群进行2×2因子设计的群体杂交实验，比较了各交配组合早期存活相关性状如受精率、孵化率、变态率以及壳长性状，评价了两个方向杂交组合平均以及不同方向杂交组合的中亲杂种优势率。结果表明早期发育阶段各组合间的受精率无显著差异，而孵化率、变态率等两个杂交方向平均的中亲杂种优势率为5.49%与12.53%，高于壳长性状的优势率（0.936-1.534%）。方差分析结果表明不同方向的杂交组合在早期发育阶段存活相关性状以及壳长性状存在显著差异。孵化率、变态率性状，S×98的中亲杂种优势率分别为13.21%与21.10%，均高于98×S的-3.84%与3.85%；而第10和25d壳长性状，S×98的中亲杂种优势率为1.14%与-2.52%，低于98×S的1.93%与4.41%。为进一步评价“98”选群与“S”选群不同交配组合在不同温度条件下的生长，进行了基因型与环境的互作研究。从“98”选群与“S”选群的4个交配组合中分别取5月龄幼鲍100头，各组合随机分成3组，每组1个重复，分别于12°C、16°C和 22°C温度条件下进行培育，比较各交配组合基因型与温度对幼鲍生长的影响。不同温度条件下，各组合壳长生长的方差分析结果表明，基因型和温度都能够对幼鲍生长以及最终壳长产生极显著的影响（P < 0. 01），它们的交互作用也达到显著水平（P < 0.05）。杂交子代的幼鲍壳长在12°C、16°C和 22°C温度条件下均表现出杂种优势，双向杂交的中亲杂种优势率分别为5.32%、5.55%和0.03%，表明低温条件（12°C），比高温条件（22°C）下有更强的杂种优势。汕头“S”选群的早期孵化率、变态率、生长性状以及低温条件下幼鲍生长性状的单亲杂种优势率分别为16.64%、42.49%、3.42~5.79%和5.73~9.15%，单亲杂种优势率较大，表明可通过杂交手段，显著地改良汕头“S”选群在早期发育阶段的生长速度、存活率以及幼鲍期的生长性状。本研究的结果支持了Lerner（1954）杂种优势的基因与环境互作学说。 5. 皱纹盘鲍幼鲍的中间培育技术研究（1）对南方越冬方式的评价目前，每年的11月前后，将6-7月龄幼鲍运往南方的闽东、闽中、闽南沿海越冬，翌年4月至6月再运回到北方（大连、山东半岛）的养殖模式已经普遍应用于皱纹盘鲍的实际生产，为评价南方越冬的幼鲍培育方式，本研究分别以不同幼鲍材料在闽东三都海湾进行了越冬培育实验。选择生产上壳长分别为18.37 ± 1.28 mm、15.89 ± 1.10 mm、14.55 ± 1.10 mm与10.59 ± 0.84 mm的幼鲍进行了为期6.5个月的越冬培育，实验结束时，存活率分别为95.56 ± 2.21%、90.55 ± 1.96%、83.97 ± 1.63%与63.30 ± 2.79%。回归分析表明，供试幼鲍在实验起始时的壳长与越冬阶段的存活率成正相关（P = 0.018 < 0.05）。该结果表明，提高幼鲍的规格可显著提高皱纹盘鲍的越冬成活率，因此对于实际生产而言，采取适当措施提高皱纹盘鲍越冬苗种的规格将大幅增加生产的收益，而采用生长速率快的品种、品系或提早采苗均可实现该目标。综合各规格组幼鲍，幼鲍在南方开放性水域进行越冬培育的平均存活率较高，可达到91.38±0.01%，从幼鲍南方越冬的存活曲线可以看出，幼鲍的死亡主要集中在从大连运至福建某地后的15天内，出现死亡高峰的原因可能是由于运输过程的胁迫。此外，2月及4月中下旬水温出现显著降低或回升时也有较明显的死亡出现。该部分结果，对皱纹盘鲍幼鲍的养成管理有指导意义，可以通过合理安排越冬时间、避开死亡的敏感期等措施减少苗种越冬阶段的死亡量。以中国大连野生群体繁育的子一代为亲本（10♀，10♂），以群体交配的方式繁育F2代个体为实验材料，分别于南方海区以及北方室内升温水方式下进行生长、存活比较，结果表明南方越冬培育方式下，幼鲍壳长的日增长率为81.37-108.89 µm•day-1，与北方室内升温培育条件相比，壳长生长提高了1.08 ~ 1.68倍；而存活率无显著差异。皱纹盘鲍幼鲍南方越冬方式的优势主要体现在鲍鱼幼鲍的生长速度加快，同时节约养殖场的能耗（2）幼鲍培育过程中的养殖密度与分选效应评价以3种规格皱纹盘鲍幼鲍为材料比较幼鲍在4个培育密度以及分选或混养条件下壳长的平均日生长及特定生长率。在南方越冬培育方式下实验进行106天，多因素方差分析结果表明实验初始幼鲍的壳长以及培育密度对壳长的生长有显著影响，而且密度效应在不同幼鲍起始规格组中有不同表现；分选没有能够提高不同规格组的生长。本研究的结果对皱纹盘鲍幼鲍的越冬培育有一定的指导作用。
其他摘要	Implementations of genetic improved varieties are fundamentals to agriculture. Looking back to the development of agriculture, genetic breeding together with cultivation techniques have brought great prosperities worldwide. However, the genetic breeding programs of aquatic organisms initiated recently, while researches on breeding techniques in aquaculture field are lacking in China. Establishment of genetic breeding system of marine animals should be based on the biological characteristics of objective animals and quantitative genetic models constructed in agricultural organisms. Pacific abalone, Haliotis discus hannai Ino is one of the most important mariculture species in northern China. Researches on gentic control of shell color, quantitative genetics relating to genetic improvement of Pacific abalone, and cultivation techniques on combined effects of sizes, stocking density and sorting on juvenile growths were reported in this study. The main results are listed as follows: 1. Phenogenetics of mutant red-shelled Pacific abalone had been analyzed by controlled mating experiments between the orange-shelled abalone and the wild-type (green-shelled) ones. Varying diets feeding were conducted to orange shell colored Pacific abalones and the wild type ones to detect the diet impacts on Pacific abalone shell coloration. Besides, growth comparison between the two types in F2 families was also carried out. Controlled mating experiments were designed to observe the segregation of the F2 generation between the orange type (O-type) and the wild type (G-type). Results show that the O-type and G-type of shell coloration is controlled by a recessive (o) and a dominant allele (G) at a single locus in the Pacific abalone genome. To detect diet impacts on Pacific abalone shell coloration, varying diets feeding were conducted to O- and G-type individuals of Pacific abalone. Results show that although the orange and green genotypes are controlled at genetic level, diets may still cause some limited variations in shell colorations within individual phenotypic lines. O- or G-type abalones always had orange or dark-brown colors when supplied with diatoms or red algae, or turned into yellow or green when fed with brown or green algae, or an artificial diets purchased commercially. On the other hand, color shifting between types O and G would never occur, which permitted us to safely assign orange and yellow as the O phenotype and dark-brown and green as the G phenotype in the study. These observations further support the notion that the shell coloration in Pacific abalones is genetically controlled, but with unique patterns in response to the diet changes. The association of ‘diet – shell coloration’ can be a morphological marker, which can be applied in the research of cultivation technique and genetic breeding in Pacific abalone, such as tagging individual or lines. All family lines occurring shell color segregation in F2 were selected and measured the shell lengths for 3-5 times for the juvenile abalones aged at 2-14 months. Among them, there were no significant differences in all groups of abalones between O and G-type juvenile abalones. It suggests that the O-type mutation has no effect on the growth of abalones. 2. Shell morphological indices analysis on selective and crossing stocks was conducted in Pacific abalone. Seven 4~6 year aged stocks, including four artificial selective stocks on growth rate and three hybrid stocks between wild geographic populations in Pacific abalone were used as materials. Shell length (L), shell width (W), shell height (H) and shell weight (Sw) were measured on 60 ~100 samples in each stock. L/(L+W+H)、W/(L+W+H)、H/(L+W+H) and Sw/(L×W×H) were calculated as shell morphological indices. Statistical methods of MANOVA and ANOVA were used to detect the significant differences in the shell morphological indices among the tested stocks. Results show that the CV (%) of the shell morphological indices are 0.34, 0.74, 2.62 and 6.54. Indices of H/(L+W+H) and Sw/(L×W×H) demonstrate high polymorphism and showed significant differences among the tested stocks, which indicated the high genetic variations. Owing to the unavailability of Sw/(L×W×H) in the practice, genetic improvement on shell shape can be selected on the index of H/(L+W+H)。 3.Genetic parameter estimates during adult stages of Pacific abalone It is necessary to estimate the genetic parameter estimates during adult stages of Pacific abalone to establish a scientific breeding system. Eight half-sib families and 21 full-sib families were obtained by a nested design. Heritabilitis of shell length at ages of 70-550d was 0.161 ~ 0.326 by sire component, and 0.312 ~ 0.977 by dam component. While, heritabilities of growth rate were 0.080 ~ 0.210 and 0.299-0.306 during 320-380 days and 490-550 days, respectively. The larger dam component estimation indicated the maternal effects still existed in the adult stages. The estimated genetic correlations between shell length at contiguous ages were consistently high, ranging from 0.597 ~ 1.000 to 0.589 ~ 1.177 by sire and dam components, respectively. Whereas, the estimated genetic correlation between growth rates at 2 phases was near 0. Because of the few sire parents in the experiment, standard errors to the genetic parameter estimated by sire component were large, however, the dam component estimation were all significantly greater than zero. The genetic correlation level between shell lengths at contiguous ages indicated the feasibility of early selection to the trait. 4. Crossing evaluation between artificial selective groups in Pacific abalone 16 crossing combinations by diallele cross between 4 artificial selective groups in pacific abalone, were established to compare the differences between the selective groups, investigate the magnitude of heterosis (mid-parent) and heterobeltiosis (better parent), and combination abilities at early stages. Additionally, a 2 × 2 factorial cross between Dalian “98” and Shantou “S” selective groups produced 4 groups to test heterosis in fertilization rate, hatching success, metamorphosis and growth at early stages. Juveniles of shell length >1.2cm from the 4 groups were treated at 3 temperatures to investigate the magnitude of heterosis on varying environments. (1) Significant differences in shell lengths at 9, 20 and 30d after fertilization between purebreds of the selective groups were detected. 97  97 performed worst in shell lengths at each stage (0.462 ± 0.023mm, 0.698 ± 0.057mm, 1.476 ± 0.234mm), while S  S performed best in shell lengths at each stage (0.522 ± 0.023mm, 0.824 ± 0.084mm, 1.798 ± 0.229mm). Heterosis and heterobeltiosis varied among shell length traits at stages of 9, 20 and 30d after fertilization. Out of the 12 crosses, six crosses showed significantly positive heterosis and three crosses exhibited significant positive heterobeltiosis in shell length at stage of 9d, with highest value of 9.05% in J  97, and 5.77% in S  J; seven crosses showed significantly positive heterosis and five crosses exhibited significant positive heterobeltiosis in shell length at stage of 9d, with highest value of 12.60% in J  97, and 12.20% in J  97; six crosses showed significantly positive heterosis and three crosses exhibited significant positive heterobeltiosis in shell length at stage of 9d, with highest value of 24.08% and 15.95% both in 97  S. “S” group had the significant and largest GCA value, and 97×S had the positive, significant and largest SCA value. These indicated the possible application of 97×S as the super crossing combination. Reciprocal effects during the early stages also demonstrated. (2) Reciprocal crosses between two selective groups “98” and “S” were carried out, and mid-parent heterosis for fertilization rate, hatching rate, metamorphosis rate and growth were studied. Furthermore, juvenile growth of the 4 F1 groups generated was tested in 3 different temperatures. Results showed significant difference in eggs sizes between the selective groups. Heterosis for hatching success, metamorphosis and early growth were 5.49%, 12.53% and 0.936-1.534%, respectively. Heterosis for juvenile growth were obtained in the varying temperatures. Significant interaction between genotype and environment indicated heterosis were larger in the lower temperature environment. Higher single-parent heterosis to “S” group showed that crossbreeding can be an effective way to improve the growth performance of “S ” groups. The present study validated the Lerner’s (1954) theory. 5. Studies on intermediate culture of juvenile Pacific abalone (1) Evaluation of juvenile over-wintering mode in southern China A new juvenile over-wintering mode of Pacific abalone was examined. Juvenile abalones were transferred to the open seas in southern China to over-winter and growth and survival were compared between varying over-wintering modes in northern and southern China. Results show: a. growth and survival of juvenile abalones were significantly affected by initial body sizes in both cultivation modes. The survival rates were in a significant linear correlation with the initial sizes ranged from SL=10.59 to 18.37mm in the southern over-wintering mode (P<0.05). That suggested the necessity of early spawning or the application of genetic improved stain to improve the initial body sizes, for the sake of obtain higher survival rate during juvenile over-wintering. b. Juvenile growth and survival rates during over-wintering period in southern China were 81.37-108.89 µm•day-1 and 91.38%, respectively. Growth rate during over-wintering in southern China increased 1.06 to 1.68 times compared to that in northern China, while no significant differences in survival rate were indicated. The superiorities of the southern over-wintering mode were in the growth performance and low-energy consuming. c. In southern over-wintering mode, juvenile mortality occurred in the initial adaptive period and periods of water temperate occurring larger fluctuations. That can indicate a guide to selection of the time of abalone over-wintering. (2) Evaluations of combined effects of initial sizes, stocking density and sorting on juvenile growths during over-wintering stages Initial size, stocking density and sorting are among the first considerations when setting up abalone adult grow-out systems. This study aimed to investigate the effects of these factors on growth of over-wintering juvenile Pacific abalone, Haliotis discus hannai Ino cultured in southern China open waters. Juvenile abalones were reared in multi-tier basket form for over-wintering in the open sea environment of southern China for 106 days. Results indicated that DGRs and SGRs of juvenile abalones were significantly affected by initial body size and stocking density. Effects of density varied with the initial size. Sorting abalones may not be necessary in practice as sorting did alter growth significantly in all densities. Causes of the combined effects on abalone growth such as genetic control and intraspecific competition were discussed. The results of this study can be readily applied in over-wintering of juvenile abalones in southern China waters.
页数	116
语种	中文
文献类型	学位论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/545
专题	海洋环流与波动重点实验室
推荐引用方式 GB/T 7714	吴富村. 皱纹盘鲍的遗传育种与养殖技术研究[D]. 海洋研究所. 中国科学院海洋研究所,2008.

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