Comparative growth and viability of hybrids between two populations of Chinese shrimp (Fennropenaeus chinensis)

Fenneropenaeus chinensis is confined to the Yellow Sea and Bohai Sea in China and the West Coast of the Korean Peninsula. Intra- and intercross populations were produced between Rushany (YP) and Korean (KN) populations. Seven traits were recorded. The heterosis of hybrids was computed and comparison between treatments was performed by ANOVA. At the fourth month after post-larvae, six indexes of growth trait and viability showed a range of heterosis, ranging from 0.514% to 14.950%. At the fifth month after post-larvae, six indexes of growth trait and viability ranged from -9.000% to 19.090%. The negative heterosis was observed in CL, HST and viability. The heterosis of KN female xYP male tended generally to increase as the age of the Chinese shrimp increased while the heterosis of YP female xKN male tended to decrease. The results indicated that the viability of reciprocal hybrids were not significantly different (P > 0.05) from their parents during the experiment. The result of ANOVA indicated that the F1 hybrids were significantly different (P < 0.05) in WST and TW at the fourth month. The multiple comparisons of LSD test indicated that the hybrids of YP female xKN male were significantly different (P < 0.05) from their parents in TW. The hybrids of YP female xKN male were significantly different (P < 0.05) from the other three combinations in WST. At the fifth months, the F1 hybrids had significant difference (P < 0.05) in body weight while other traits showed no significant differences (P > 0.05) from their parents. The multiple comparisons of LSD test indicated that the hybrids of KN female xYP male were significantly different (P < 0.05) from the KN parents in TW. The results indicate that in experimental conditions, the F-1 hybrids created from two populations of Chinese shrimp showed a certain level of heterosis for growth performance and viability. The crossing scheme may improve growth performance and viability in Chinese shrimp, but the improvement may be limited because effective crossbreeding requires the maintenance of pure, preferably inbred, lines and possibly involves specialized sire and dam lines. Therefore, the exploitation of heterosis through single crossbreeding in Chinese shrimp is of limited utility in practical commercial shrimp aquaculture in spite of the potential of significant heterosis. The crossbreeding of different populations can be applied in the establishment of base populations.

Mesozoic-Cenozoic tectonic evolution of the Zhuanghai area, Bohai-Bay Basin, east China: the application of balanced cross-sections

The technique of balancing cross-sections, an important method for studying the tectonic history of sedimentary basins, has many applications. It enables one to compile charts for petroleum exploration and development, and growth sections of ancient structures can be restored so that the structural growth history can be studied. In order to study tectonic evolution in the Zhuanghai area of the Bohai-Bay basin, we selected two seismic profiles and compiled two structural growth sections. Based on the two balanced cross-sections, the evolution can be divided into four phases: the Triassic-Middle Jurassic phase, Late Jurassic - Cretaceous phase, Palaeogene extension phase, and Late Palaeogene-to-present phase. The whole area was uplifted during the Triassic-Middle Jurassic phase because of intense extrusion stress related to the Indo-China movement. During the Late Jurassic and Early Cretaceous, intense extension occurred in east China, and the whole area rifted, leading to the deposition of a thick sedimentary sequence. In the Late Cretaceous, the area suffered uplift and compression associated with the sinistral strike slip of the Tanlu fault. In the Palaeogene, a rifting basin developed in the area. Finally, it became stable and was placed in its present position by dextral strike-slip motion. In addition, some problems associated with compiling balanced cross-sections are discussed.

Analysis on deep crustal structure along the onshore-offshore seismic profile across the Binhai (littoral) fault zone in northeastern South China Sea

The onshore-offshore deep seismic experiment was carried out for the first time and filled the blankness of the seismic surveys in the transition area between South China and northeastern South China Sea. The seismic data were analyzed and processed. The different seismic phases were identified and their travel time arrivals were modeled by ray-tracing to study the P-wave velocity crustal structure of this area. The crustal structure of this area is the continental crust. The crust thickness is gradually decreasing southward along the on-shore-offshore seismic line. The low-velocity layer (5.5 similar to 5.9 km (.) s(-1)) exists generally in the middle crust (about 10.0 similar to 18.0km)with about 2.5 similar to 4.0 km thickness, which is also thinning seaward. No obvious high-velocity layer appears in the lower crust. The Binhai (littoral) fault zone is a low velocity zone, which is located about 35km southeast to the Nan'ao station and corresponding to the gradient belt of gravity & magnetism anomalies. The depth of the fault zone is close to the Moho discontinuity. The littoral fault zone is a boundary between the normal continental crust of South China and the thinned continental crust of the sea area.

The paleoclimatic events and cause in the Okinawa Trough during 50 kaBP

Planktonic foraminiferal delta O-18 record for core DGKS9603 from the Okinawa Trough shows a series of climatic fluctuations and sudden cooling events in short time scale during 50 kaBP, which appear to correlate closely to the Younger Dryas and Heinrich events H1-5 recorded in Chinese loess, the South China Sea, the North Atlantic cores and the Greenland ice cores. Three polarity reversal events, correlating to Gothenburg, Mungo and Laschamp events, approximately correspond to Heinrich events H1, H3 and H5 respectively, which could be a cause of global climate changes. The delta O-18 curve of the Okinawa Trough is well associated with the grain size record of the Lijiayuan loess profile in northwestern China and is somewhat different from the climate fluctuations documented in the Greenland ice cores. These correlation results indicate that regional factors play an important role in controlling the climate changes in the East Asia, and the East Asian Monsoon could be the prominent regional controlling factor.

Source of a floating dust episode over the Qingdao region and dust throughput to the ocean

A floating dust weather happened on March 11-12, 1995 over the Qingdao region. Its sources and throughput to the ocean were studied. The result indicated that the floating dust was caused by the dust storm that starred in northwestern China and developed in northern China. 21 x 10(6)t fine soil particles were carried to the ocean during the episode.

Simulating a typhoon storm surge in the East Sea of China using a coupled model

A coupled numerical model with a 2' x 2' resolution grid has been developed and used to simulate five typical typhoon storm surges (5612, 7413, 7910, 8114, and 9711) in the East Sea of China. Three main driving forces have been considered in this coupled model: wave radiation stress, combined wave-current bottom shear stress and wave-state-dependent surface wind stress. This model has then been compared with in situ measurements of the storm set-up. The effect of different driving force components on the total storm surge has also been investigated. This study has found that the coupled model with high resolution is capable of simulating the five typical typhoons better than the uncoupled models, and that the wave-dependent surface wind stress plays an important role in typhoon storm surge-wave coupling in this area and can increase the storm set-up by 1 m. The study of the five typhoon cases has shown that the general coupling effects could increase storm set-up by 20-32%. Thus, it is suggested that to predict typhoon storm surges in the East Sea of China, a storm surge-wave coupled model be adopted. (C) 2008 National Natural Science Foundation of China and Chinese Academy of Sciences. Published by Elsevier Limited and Science in China Press. All rights reserved.

Metabolism of polychaete Neanthes japonica Izuka: relations to temperature, salinity and body weight

Polychaete Neanthes japonica is a species geographically specific in China and Japan with important scientific implication and commercial value. In this study, the relations of body weight, salinity and temperature to oxygen consumption and ammonia excretion of N. japonica were determined. Three different groups in body weight (large: 2.34 +/- 0.36 g, middle: 1.50 +/- 0.21 g and small: 0.62 +/- 0.12 g) were set for all experiments. Results show that the body weight is negatively related to the rates of oxygen consumption and ammonia excretion; and the relationship is significant. The oxygen consumption and ammonia excretion at 24A degrees C decreased at salinity from 5 to 30 and increased above 30, indicating that both lower and higher salinity are adverse and certain degree of salinity stress is necessary for enhancing the energy demand. At salinity 30, rising temperature from 18A degrees C to 30A degrees C, the oxygen consumption increased before 27A degrees C and then decreased. However, the relation of ammonia excretion and temperature seems more complex. Two-way ANOVA shows that salinity, temperature and body weight all have a significant effect on the oxygen consumption and ammonia excretion of the worm. Moreover, interaction between salinity/temperature and body weight is also significant. O:N (oxygen/nitrogen) ratio varies greatly in this case from 5.97 to 463.22, indicating that N. japonica can regulate the type of metabolic substrate against environment changes.

LABORATORY HYBRIDIZATION BETWEEN CRASSOSTREA ARIAKENSIS AND C. SIKAMEA

TO understand possible reproductive interaction between Crassostrea ariakensis (Fujita, 1913) and C. sikamea (Amemiya, 1928), which coexist ill estuaries of China and Japan, we conducted 2 X 2 factorial crosses between the two species. Asymmetry in fertilization success was observed where C. sikamea eggs can be fertilized be C. ariakensis the receprocal cross resulted in no fertilization. Fertilization Success ill C.sikamea female X C. ariakemvis male (SA) crosses was lower than that in the two intraspecific crosses and produced larvae that had similar growth the rate as their maternal species during the first nine days because of maternal effects. After that, genome incompatibility casted negative effects on the growth and survival of the hybrid larvae. Most hybrid larvae died during metamorphosis. but a small number of spat survived. Genetic analysis revealed that the survived SA spat contained DNA from both species and were the hybried. This study demonstrates that hybridization between C. ariakensis and C. sikamea is possible in one direction.

The possibility analysis of habitats, origin and reappearance of bloom green alga (Enteromorpha prolifera) on inshore of western Yellow Sea

Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008, authors analyze the necessary conditions and possible water area in China producing a large biomass, some reasons for firestorm, and the possibility of the reappearance of marine bloom green alga Enteromorpha prolifera. The change of habitats and the increase of nutritional levels related to the water area could be considered as direct reasons. It was transferred northward by the combination of the flow of rainwater, wind and alongshore marine current. The original region of large biomass produced is possibly located in the southwestern Yellow sea. It will possibly be appearing again in the coming years or in the future. A summary is also given referring to its reproduction, development and distribution worldwide.

Studies on Chinese species of Gelidiella and Pterocladiella (Gelidiales, Rhodophyta)

A detailed study of materials from our herbarium shows the presence of two species of Gelidiella and three species of Pterocladiella, including two new records and a new species. Previously recorded species include G. acerosa and P. capillacea. G. bornetii and P. caerulescens are new records for China and P. yinggehaiensis is believed to be a new species. This new species is characterized by its small thalli, 1.5-2 cm high, that are more densely branched on the middle to upper parts for one half their lengths. These characteristics are so distinctive that they can be used to separate this species readily from other species now reported in this genus.

The unique skeleton of siliceous sponges (Porifera; Hexactinellida and Demospongiae) that evolved first from the Urmetazoa during the Proterozoic: a review

Sponges (phylum Porifera) had been considered as an enigmatic phylum, prior to the analysis of their genetic repertoire/tool kit. Already with the isolation of the first adhesion molecule, galectin, it became clear that the sequences of sponge cell surface receptors and of molecules forming the intracellular signal transduction pathways triggered by them, share high similarity with those identified in other metazoan phyla. These studies demonstrated that all metazoan phyla, including Porifera, originate from one common ancestor, the Urmetazoa. The sponges evolved prior to the Ediacaran-Cambrian boundary (542 million years ago [myr]) during two major "snowball earth events", the Sturtian glaciation (710 to 680 myr) and the Varanger-Marinoan ice ages (605 to 585 myr). During this period the ocean was richer in silica due to the silicate weathering. The oldest sponge fossils (Hexactinellida) have been described from Australia, China and Mongolia and are thought to have existed coeval with the diverse Ediacara fauna. Only little younger are the fossils discovered in the Sansha section in Hunan (Early Cambrian; China). It has been proposed that only the sponges possessed the genetic repertoire to cope with the adverse conditions, e.g. temperature-protection molecules or proteins protecting them against ultraviolet radiation. The skeletal elements of the Hexactinellida (model organisms Monorhaphis chuni and Monorhaphis intermedia or Hyalonema sieboldi) and Demospongiae (models Suberites domuncula and Geodia cydonium), the spicules, are formed enzymatically by the anabolic enzyme silicatein and the catabolic enzyme silicase. Both, the spicules of Hexactinellida and of Demospongiae, comprise a central axial canal and an axial filament which harbors the silicatein. After intracellular formation of the first lamella around the channel and the subsequent extracellular apposition of further lamellae the spicules are completed in a net formed of collagen fibers. The data summarized here substantiate that with the finding of silicatein a new aera in the field of bio/inorganic chemistry started. For the first time strategies could be formulated and experimentally proven that allow the formation/synthesis of inorganic structures by organic molecules. These findings are not only of importance for the further understanding of basic pathways in the body plan formation of sponges but also of eminent importance for applied/commercial processes in a sustainable use of biomolecules for novel bio/inorganic materials.

In vivo antitumor and immunomodulation activities of different molecular weight Lambda-Carrageenans from Chondrus ocellatus

lambda-Carrageenan is a sulfated galactan isolated from some red algae and have been reported to have many kinds of biological activities. lambda-Carrageenan from Chondrus ocellatus, an important economic alga in China and many other parts of the world, was degraded by microwave, and obtained five products that have different molecular weight: 650, 240, 140, 15, 9.3 kDa. Analytical results confirmed that microwave degradation might not change the chemical components and structure of polysaccharides under certain condition. In this study, tumor-inhibiting activities, weight of immune organ, nature killer cells activity, lymphocyte proliferation ratio and pathological slice of spleen and tumor cells from the control group and lambda-carrageenan-treated mice of transplanted S 180 and H22 tumor were investigated. The results indicated that the five lambda-carrageenan samples all showed antitumor and immunomodulation activities in different degree. Molecular weight of polysaccharides had notable effect on the activities. In addition, their antitumor and immunomodulation have some relevance and the five lambda-carrageenans probably inhibited tumor by means of activating the immunocompetence of the body. Among all the experiment results, samples with the highest activities are PC4 and PC5 whose molecular weight are 15 and 9.3 kDa. (C) 2003 Elsevier Ltd. All rights reserved.

Experimental evaluation of heterobeltiosis and heterosis between two populations of Pacific abalone Haliotis discus hannai Ino

A2 x 2 factorial cross between two populations of Pacific abalone Haliotis discus hannai Ino, collected separately from Dalian (D) in China and Miyagi (M) in Japan, was conducted to compare performances in fertilization rate, hatching rate, metamorphosis rate and growth at days 20, 43, 160 and 330 between purebreds (DD and MM) and crossbreds (DM and MD) and investigate the magnitude of heterobeltiosis (better parent) and heterosis (mid-parent). Heterobeltiosis and heterosis for all the traits analyzed were evidently different between crossbreds DM and MD. Heterobeltiosis in the crossbred DM varied among traits, with values of 2.5% for the fertilization rate, 2.2% for the hatching rate, -1.9% for the metamorphosis rate and 7.4% for the growth at the (lay 330. The crossbred DM displayed positive heterotic values for fertilization rate (5.4%), hatching rate (7.4%), metamorphosis rate (7.6%) and growth (12.0%) at the day 330. However, both heterobeltiosis and heterosis for all the traits in the crossbred MD were negative except those for the growth at days 20 and 43. The results indicate the importance of selecting superior hybrid varieties if the exploitation of hybrid vigor is considered in the Pacific abalone breeding program.

Genetic improvement on Chinese shrimp (Fenneropenaeus chinensis): growth and viability performance in F1 hybrids of different populations

Fenneropenaeus chinensis distributed in the Yellow Sea and Bohai Sea of China and the west coast of the Korean Peninsula. Different geographical populations represent potentially different genetic resources. To learn further the characteristics of different geographical population, crosses among two wild and three farmed populations were produced. The two wild populations were from the Yellow Sea and Bohai Sea (WYP), and the west coast of the Korean Peninsula and coast (WKN). The three farmed populations included the offspring of first generation of wild shrimp from coast in Korea (FKN), the Huang Hai (the Yellow Sea in Chinese) No.1 (HH1), and JK98. The phenotypes growth and survival rates of these populations were compared to confirm the feasibility for crossbreeding. The body length (BL), carapace length (CL), carapace width (CW), height of the second and third abdominal segment (HST), width of the second and third abdominal segment (WST), length of the first abdominal segment (LF), length of the last abdominal segment (LL), live body weight (BW), and survival rate were measured. Different combinations were statistically performed with ANOVA and Duncan's Multiple Range Test. The results show that the survival rate of JK98(a (TM) Euro)xWKN(a (TM),) was the highest, followed by WYP(a (TM) Euro)xWKN(a (TM),), FKN(a (TM) Euro)xWYP(a (TM),), FKN(a (TM) Euro)xHH1(a (TM),) and WYP(a (TM) Euro)xFKN(a (TM),); the body weight of FKN(a (TM) Euro)sxHH1(a (TM),) was the highest, followed by FKN(a (TM) Euro)xWYP(a (TM),), WYP(a (TM) Euro)xWKN(a (TM),), WYP(a (TM) Euro)xFKN(a (TM),) and JK98(a (TM) Euro)xWKN(a (TM),); the total length had the same ranking as the body weight. All growth traits in hybrids JK98(a (TM) Euro)xWKN(a (TM),) were the lowest among all combinations. F1 hybrids had significant difference (P < 0.05) in BL, CL, HST, LL, and BW; and insignificant difference (P > 0.05) in other growth traits and survival rate. The results of Duncan's Multiple Range Test are that BL and CL of JK98(a (TM) Euro)xWKN(a (TM),) were significantly different from the other combinations; HST different from the combination of FKN(a (TM) Euro)xWYP(a (TM),), FKN(a (TM) Euro)xHH1(a (TM),) and WYP(a (TM) Euro)xWKN(a (TM),); and BW different from FKN(a (TM) Euro)xWYP(a (TM),) and FKN(a (TM) Euro)xHH1(a (TM),). As a whole, the results indicate that the FKN(a (TM) Euro)xHH1(a (TM),) was the best combination in all growth traits. Therefore, hybridization can introduce the variation to base populations. The systematic selection program based on additive genetic performance may be more effective than crossbreeding.

Comparison of the total amount of eggshell pigments in Dongxiang brown-shelled eggs and Dongxiang blue-shelled eggs

Based on the knowledge of the heme biosynthetic and metabolic pathway and the structures of biliverdin and protoporphyrin, experiments were carried out to compare the difference between the total quality of eggshell pigments in blue-shelled eggs and brown-shelled eggs from the same population (Dongxiang, China) and to analyze the correlation between the quantity of protoporphyrin and biliverdin in the 2 kinds of eggshells. It was found that there was no significant difference between the total quantity of eggshell pigments in Dongxiang blue-shelled eggs and Dongxiang brown-shelled eggs (P = 0.9006), and a highly significant positive correlation between the quantity of protoporphyrin and biliverdin in blue eggshells (P < 0.01) and a significant positive correlation between the quantity of protoporphyrin and biliverdin in brown eggshells (P < 0.05). These results suggested that eggshell protoporphyrin and eggshell biliverdin probably derived from common precursor material.