Effects of Microbial Fermented Feed on Growth and Development of Farmed Crayfish

Microbial fermented feed possesses a natural fermentation flavor and exhibits good palatability.It is not only easily digestible and absorbable by livestock but also non-toxic.Additionally,it has the capacity to inhibit the proliferation of pathogenic bacteria,facilitate the growth and development of animals,and enhance their immune response,disease resistance,and overall production performance.This paper summarizes the selection of common feed materials and microbial strains used in fermented feed,as well as their effects on the growth performance,muscle quality,antioxidant capacity,and immune function of crayfish.The aim of this study is to provide a reference for the further popularization and application ofmicrobialfermented feed in crayfishaquaculture.

Effects of Water-retaining Agents on Growth, Development, Yield and Quality of Soybean under Drought Stress

[Objectives]The paper was to explore the effects of different doses of water-retaining agent on the growth and development indicators,yield and quality of soybean plants subjected to drought stress.[Methods]The effects of drought stress(MDS)and drought stress with low(MDS-L),medium(MDS-M)and high doses(MDS-H)of the water-retaining agent on the growth and development indicators,root activity,MDA content,antioxidant enzyme activity,yield and quality of soybean were studied by field plot test,with the normal water supply serving as the control(CK).[Results]In response to drought stress,the plant height,stem diameter,and yield of soybean exhibited a notable decline.Additionally,the contents of protein,fat,linoleic acid,and linolenic acid in seeds demonstrated a significant reduction.Conversely,the root activity and antioxidant enzyme activity exhibited a noticeable decline,while the MDA content exhibited an increase.The application of varying doses of the water-retaining agent was found to significantly enhance soybean growth,stimulate root activity,and elevate antioxidant enzyme activity,while concurrently reducing MDA content.The observed effects were found to be dose-dependent,with the greatest effects observed at the highest dose.In comparison to MDS,the yields of soybean in the MDS-L,MDS-M,and MDS-H treatments exhibited a 18.38%,25.58%,and 46.26%increase,respectively.Additionally,the content of protein,fat,linoleic acid,and linolenic acid in seeds demonstrated a notable enhancement.[Conclusions]The application of the water-retaining agent has been demonstrated to significantly promote the growth of soybean plants under conditions of drought stress,resulting in an improvement in both the yield and the quality of the soybean crop.The recommended dosage of the water-retaining agent is 3.3 kg/667 m 2.

Effects of different forms of yeast Saccharomyces cerevisiae on growth performance,intestinal development,and systemic immunity in early-weaned piglets

The present study was conducted to determine effects of different forms of yeast （Saccharomyces cerevisiae, strain Y200007） on the growth performance, intestinal development, and systemic immunity in early-weaned piglets. A total of 96 piglets （14-d old, initial average body weight of 4.5 kg） were assigned to 4 dietary treatments： （1） basa diet without yeast （Control）; （2） basal diet supplemented with 3.00 g/kg live yeast （LY）; （3） basal diet supplemented with 2.66 g/kg heat-killed whole yeast （HKY）; and （4） basal diet supplemented with 3.00 g/kg superfine yeast powders （SFY）. Diets and water were provided ad libitum to the piglets during 3-week experiment. Growth performance of piglets was measured weekly. Samples of blood and small intestine were collected at days 7 and 21 of experiment. Dietary supplementation with LY and SFY improved G：F of piglets at days ]-21 of the experiment （P 〈 0.05） compared to Control group. Serum concentrations of growth hormone （GH）, triiodothyronine （T3）, tetraiodothyronine （T4）, and insulin growth factor 1 （iGF-1） in piglets at day 21 of the experiment were higher when fed diets supplemented with LY and SFY than those in Control group （P 〈 0.05）. Compared to Control group, contents of serum urea nitrogen of piglets were reduced by the 3 yeast-supplemented diets （P 〈 0.05）. Diets supplemented with LY increased villus height and villus-to-crypt ratio in duodenum and jejunum of piglets （P 〈 0.05） compared to other two groups at day 7 of the experiment. Feeding diets supplemented with LY and SFY increased （P 〈 0.05） serum concentrations of IgA, IL-2, and IL-6 levels in piglets compared to Control. The CD4＋/CD8＋ ratio and proliferation of T-lymphocytes in piglets fed diets supplemented with LY were increased compared to that of Control group at day 7 of the experiment （P 〈 0.05）. In conclusion, dietary supplementation with both LY and SFY enhanced feed conversion, small intestinal development, and systemic immunity in early-weaned piglets, with better improvement in feed conversion by dietary supplementation with LY, while dietary supplementation with SFY was more effective in increasing systemic immune functions in early-weaned piglets.

Effect of early nutrition on intestine development of intrauterine growth retardation in rats and its correlation to leptin

AIM：To investigate the intestine and body development of intrauterine growth retardation（IUGR）rats under early different protein diet and to analyze the correlation between leptin and intestine and body development．METHODS：An IUGR rat model was established by food restriction of pregnant female rats．Fifty-six neonatal IUGR rats and 24 neonatal normal rats were randomly divided into normal control group（Cgroup），IUGR model group （scgroup），low protein diet IUGR group（SL group），and high protein diet IUGR group（SH group）．Eight rats were killed per group at wk 0，4，and 12．Serum leptin，body weight（BW），body length（BL），intestinal weight（IW），intestinal length（IL），andintestinal disaccharidase（including lactase，maltase，and saccharase） were detected．RESULTS：BW（4．50±0．41g），BL（5．96±0．40cm），IW（0．05±0．01g），and IL（15.9±2．8cm）in neonatal IUGR rats were much lower than those in Cgroup（6．01±0．55g，6．26±0．44cm，0．10±0．02g，21.8±2．7cm，P〈0．05），while intestinal lactase and maltase activities were higher than those in Cgroup．SH group showed the fastest catch up growth and their BW，BL，IW，and IL reached the Cgroup level at wk 4．SC group showed relatively slower catch up growth than SH group，and their BW，BL，IW did not reach the Cgroup level at wk 4．SL group did not show intestine and body catch up growth．Intestinal maltase [344±33μmol／（min·q）]and saccharase activities[138±32μmol／（min·g）]in SL group were both markedly lower than nose in C group [751±102，258±271μmol／（min·g），P〈0．05]．There were no significant difierences in lactase activities at wk 4 and disaccharidase activities at wk 12 among all groups（P〈0．05）．The leptin level in SL group（0．58±0．12ng／mL） was the highest in all groups，and much lower in SH group（0．21±0．03ng／mL） than that in any other IUGR groups at wk 4（P〈0．05）．Leptin was negatively related to BW （r=-0．556，P=0．001），IW（r=-0．692，P=0．001） and IL（r=-0．738，P=0．000）at wk 4，while no correlation was found at wk 12．CONCLUSION：High protein diet is a reasonable early nutritional mode to IUGR rats in promoting intestine and body catch up growth．

11β-hydroxysteroid dehydrogenase types 1 and 2. in postnatal development of rat testis： gene express,on, localization and regulation by luteinizing hormone and androgens

11β-hydroxysteroid dehydrogenase type 1 （11β-HSD1） and type 2 （11β-HSD2） are expressed in rat testis, where they regulate the local concentrations of glucocorticoids. Here, we investigated the expression and localization of 11β-HSD in rat testis during postnatal development, and the regulation of these genes by luteinizing hormone （LH） and androgens, mRNA and protein levels were analyzed by quantitative real-time-polymerase chain reaction and western blotting, respectively, in testes collected from rats at postnatal day （PND） 7, 14, 21, 35, and 90, and from rats treated with LH, 7α.methyl-19-nortestosterone （MENT） and testosterone at PND 21 and PND 90. Immunohistochemical staining was used to identify the localization of the 11β-HSD in rat testis at PND 7, 14, and 90. We found that 11β-HSD1 expression was restricted to the interstitial areas, and that its levels increased during rat testis development. In contrast, whereas 11β-HSD2 was expressed in both the interstitial areas and seminiferous tubules at PND 7, it was present only in the interstitial areas at PND 90, and its levels declined during testicular development. Moreover, 11β-HSD1 mRNA was induced by LH in both the PND 21 and 90 testes and by MENT at PND 21, whereas 11β-HSD2 mRNA was induced by testosterone and MENT in the PND 21 testis and by LH in the PND 90 testis. In conclusion, our study indicates that the 11β-HSD1 and 11β-HSD2 genes have distinct patterns of spatiotemporal expression and hormonal regulation during postnatal development of the rat testis.

EXPRESSION AND LOCALIZATION OF SMAD4 PROTEIN IN RAT TESTIS DURING THE POSTNATAL DEVELOPMENT

Objective.To study expression and localiza tion of Smad4protein,the common-mediator Smad,which is one of intracellular signaling molecules of transforming growth factor-afamily,in rat t estis during postnatal development.Methods.In this study,whole testes were co llected from S.D rats aged3days,7days,14days and28days,and adult respe ctively.We examined the cellular localization and developmental change of Smad 4in rat testis by immunohistochemical ABC method with glucose oxidase-DAB-nic kel enhancement technique;the quantitative analysis of the immunostaining by t he image analysis system;the Smads pro-teins coexistence in the adult rat test is by the double immune staining for CD14-Smad4and Smad2-Smad4;the prote in expression of Smad during rat testicular development by means of Western blo ts.Results.The protein of Smad4was present in rats from3days of age to adul thood,and the im-munolocalization was exclusively localized to the cytoplasm o f Leydig cells with negative nuclei in the in-terstitial tissue at any time po int.No expression was detected in germ cells.The result of image and sta-tis tical analysis showed that generally,there was a tendency that the expression o f Smad4in the testes increased gradually with the rats developing maturation.C onclusion.Our data provide direct evidence for the molecular mechanism of TGF-aaction in rat testes during postnatal development and spermatogenesis of ra ts.

Testis Development and Ultrastructural Features During Spermatogenesis in Cultured Small Yellow Croaker,Larimichthys polyactis

The small yellow croaker Larimichthys polyactis is an economically important marine fish in Northeast Asia.Currently,its natural resources are threatened by overfishing and environmental pollution.Therefore,research on the reproductive system of the fish is crucial.Here,we studied the testis development and ultrastructural features of spermatogenesis in cultured L.polyactis using anatomical,histological,and ultrastructural techniques.A pair of testes,consisting of a central sperm duct and radial seminiferous lobules,were observed.The reproduction cycle of testes can be divided into stages I–VI.March to May was confirmed as the breeding season for male L.polyactis,while April is the ideal period for artificial breeding.The male L.polyactis can attain sexual maturity within 1 year.The spermatogenesis of L.polyactis comprised spermatogonium,spermatocyte,spermatid,and mature spermatozoon.The morphology of spermatogenic cells changed obviously during spermiogenesis,including nuclear shaping,midpiece and flagellum formation.The mature sperms consist of an ellipsoidal head,a short midpiece,and a long flagellum.The anterior of the head with a kidney-shaped nucleus can be distinguished.The midpiece is located posterior to the head and includes four to six spherical mitochondria.The flagellum has irregular lateral fins.The testis of L.polyactis is an unrestricted lobular type,with cystic spermatogenesis,type II spermiogenesis,and type II spermatozoa.These features are highly similar to those of other Sciaenid species.Our findings provide useful insights into the mechanism underlying testis development and spermatogenesis of L.polyactis,which can facilitate the artificial breeding of this species.

Comparison of Growth and Development Traits among Crossbreds of Dorset and Local Sheep Varieties in Gansu Province

In order to improve the meat production performance of local sheep varieties in Gansu Province, Dorset was introduced to crossbreed with the local sheep varieties, including Tan sheep, Small Tail Han sheep and Mongolia sheep. The offspring of different crossbreeding combinations were sampled randomly at different growth stages, and their growth and development traits were measured so as to screen out the best crossbreeding mode. The results showed that under the same crossbreeding mode, the growth rate of F3 was higher than that of F2, and of F2 was higher than that of F1. Among the F3 population, the growth rates of Dorset ×Han and Dorset × Mongolia hybrids were higher. Compared with those of Dorset ×Tan F3 hybrids, the body weights of male and female Dorset × Han and Dorset ×Mongolia F3 hybrids were increased by 5.59%, 4.40%, 5.93% and 3.76%, respectively. Among the F2 population, the growth rates of Dorset × Han and Dorset ×Mongolia hybrids were also higher. The body weights of male and female Dorset ×Han and Dorset × Mongolia F2 hybrids were higher than those of Dorset × Tan ×Han F2 hybrids by 5.99%, 3.67%, 9.80% and 5.00%, respectively. In the F1 population, the growth rates of Dorset × Han and Dorset × Mongolia hybrids were higher.Compared with those of Tan × Han F1 hybrids, the body weights of male and female Dorset × Han and Dorset × Mongolia F1 hybrids were increased by 11.32%,5.22%, 7.60% and 7.20%, respectively. Therefore, in the feeding area of Small Tai Han sheep, Mongolia sheep and Tan sheep, Dorset was the best sire for producing hybrid lambs. The economic benefit of crossbred offspring was obvious.

Dynamic Characteristics of Growth and Development of Xiangsha Taro in Jingjiang

The growth and development of Jingjiang Taro [Colocasia esculenta（L.） Schott] were observed, laying foundation for highly-yielding cultivation technology system of Xiangsha taro. The results indicate that germination of the second taro happened from 46 d after sprouting （7-8 leaves）; the first taro began to expand, from 125 d after sprouting （12 leaves） when the the second taro was been formed; the third taro began to form from 141 to 150 d after sprouting （15-16 leaves）. The fresh weight of the second and third taros quickly increased from the time of 15 leaves to harvest. Early September is a transformation term of Xiangsha taro from vegetative body dominant to corm growth dominant.

Effects of Nitrogen Application Amount on Growth Characteristics,Boll Development and Lint Yield of High Quality Cotton

[Objective] This study aimed to explore an optimum application amount of nitrogen for cotton cultivation. [Method] In this study, a field experiment was conducted to investigate the effects of nitrogen application amount on the growth characteristics, boll development and lint yield of high quality cotton line FZ-1. [Result] Compared with the nitrogen level of 225 kg/hm2, the lint yield had increased by 28.46% and 18.73%, respectively, with the nitrogen application amount of 300 and 375 kg/hm2. When the nitrogen application amount had increased from 225 to 300 kg/hm2, boll number per plant, boll weight and lint yield had significantly increased. At the nitrogen level of 375 kg/hm2, however, the effects of increasing lint yield were significantly less than that at the nitrogen level of 300 kg/hm2. Compared with the nitrogen levels of 225 and 375, 300 kg/hm2 of nitrogen was the optimum application amount to improve the plant height, daily increment of plant height, number of fruit branches, number ratio of nodes to fruit branches, boll volume and seed cotton weight per boll. [Conclusion] The rational management of nitrogen is the most effective way to promote the growth and development of cotton plants, ensure high yielding ability and minimize the environmental pollution caused by the overuse of nitrogen. This study had provided a sound nitrogen application strategy for the cultivation of this high-quality cotton line in the field plantation.

Effects of Light Intensity on Growth, Development and Formation on Fagopyrum cymosum

Effects of light intensity on growth, development and formation on Fagopy- rum cymosum were explored with natural light intensities at 100%（A）, 85.2%（B）, 75.8%（C） and 59.7%（D）. The results showed that the decline of light intensity re- duced nutrient growth period, so that plant growth stage entered in advance and extended, which indicated that the decline of light intensity would lower leaf number and area, the number of twigs from the stem, as well as photosynthate. Further- more, the reduction degree increased upon light intensity decrease degree, and the proper shading improved stem height and leaf area enhanced before growth term.

Study on Growth and Development Rules and Growth Curve Fitting of Minghua Black Minks

Growth curves of Minghua black minks at 0-180 days old were fitted and analyzed by using two growth models Logistic and Gompertz. The results showed that the growth curves of Minghua black minks could be fitted very well by Logistic model and Gompertz model （the degree of fitting FF≥0.99）, but Gompertz model was better at fitting and predicting their weight.

The Impact of Lead Stress on Growth and Development of Two Varieties of Wheat

[Objective] This study was to explore the impact of lead stress on growth of wheat.[Method]Taking two wheat varieties Ningchun No.13 and Ningchun No.4 as experimental materials,the growth and development of wheat under the stress of different concentration of stress was studied using potting method.[Result]With the increase of externally applied Pb,the plant height of two wheat varieties tested assumed a falling trend.When stressed by low concentration of Pb（lower than 200 mg/kg）,the fresh weight and dry weight of both varieties rose with the increase of Pb concentration;however,once exceeded 200 mg/kg,they totally showed a decline trend.Under a same fertilization level,root-stalk ratios of Pb-stressed-plants of two varieties were lower than that normally grown,of two varieties Ningchun No.13 performed better than Ningchun No.4.Higher concentration of Pb（200-800 mg/kg）severely blocked the physiological-chemical activity of both wheat varieties,which hindered the accumulation of N,P and K.[Conclusion]Our results provided theoretical basis for taking reasonable cultivation countermeasures for the Pb-polluted paddy field.

Study on Growth and Development and Dry Matter Production of Greenhouse Tomato in North China

[Objective] This study aimed to investigate the growth and development and dry matter production and allocation of greenhouse tomato in North China. [Method] With tomato cultivar ＇Jinguo No.l＇ as the experimental material, the ex- periments were conducted in a solar greenhouse located in Taigu, Shanxi （37o25＇ N, 112o25＇ E） from March to July, in 2014 and 2015. [Result] The plant height, leaf number, leaf area and dry matter production of greenhouse tomato increased lin- early with the increased days after transplantation, and their growth rates were 2.74 cm/d, 0.32 leaf/d, 70 cm2/d and 9.4 g/（m2.d）, respectively. The fruit dry weight also showed a linear relationship with the plant dry weight. After fruit setting, the fruit dry weight was increased by about 0.69 g when the plant dry weight was increased by 1 g. The allocation proportions of dry matter in tomato roots, stems and leaves de- clined significantly from plant flowering to fruiting, while the proportion of fruit dry weight in plant dry weight increased significantly, exceeding 60%. There was a strong linear relationship between dry matter production of tomato and effective cu- mulative temperature （sum of temperature higher than 10 ^（3） in the solar green- house, and the dry matter production was increased by about 0.73 g/m2 when the effective cumulative temperature was increased by one unit. The dry matter produc- tion of tomato plant also showed a strong linear relationship with photosynthetic ac- tive radiation （PAR） in the greenhouse, and about 3.4 g of dry matter was synthe- sized per unit （M J） of PAR. [Conclusion] Extending the growing period and improv- ing the temperature and light conditions could increase the dry matter production of tomato.

Studies on hybridization effects of different geographic populations of Chlamys farreri Ⅱ.The medium-term growth and development of Chlamys farreri populations from China and Russia and their reciprocal crosses

Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultural population (CC) (?) × Russian population (RW) (?) , Chinese wild population (CW) (?) × Russian population (RW) (?), Russian population (RW) (?) × Chinese wild population (CW) (?) , the study of the medium-term (6, 8, 10, 12 months) growth and development of Chlamys farreri was carried out. The four determined results indicated that there existed different extent heterosis (3% -52%) for the growth in three types of F1 hybrids, and the offspring derived from CC(?) ×R(?) had a stronger heterosis among the crosses at the medium-term; the uptrend among traits are wet weight >shell width>shell length> shell height, Chinese cultural population could be recognized as excellent parent, and seasonal variations influence very much on the daily increment and growth rate of each trait of Chlamys farreri and it is only able to survive and could barely grow in winter (6-8 months), but grows fast in temperate season (10-12 months).

Effects of Salinity on Embryonic Development, Survival, and Growth of Crassostrea hongkongensis

This study examined the effects of salinity on embryonic development, survival, and growth of the Hong Kong oyster Crassostrea hongkongensis. The embryos, larvae, and juveniles of C. hongkongensis were held in artificial seawater at three different salinities(low, 15; medium, 23; and high, 30) to determine the optimum hatchery and nursery conditions for mass production of the seeds. Results showed that the percentage production of straight-hinged larvae from fertilized eggs was significantly lower at the high salinity than at the low- and medium-salinities(P < 0.05). The survival rates of larvae and juveniles differed significantly among the three salinity trials, with the highest survival rate observed at the low salinity(P < 0.05). The shell height of larvae was significantly larger at the low salinity than at the high and medium salinities from days 9 to 15(P < 0.05), whereas that of juveniles was significantly larger at the low salinity than at the high and medium salinities on day 70(P < 0.05). These results indicate that the larvae and juveniles of C. hongkongensis are tolerant to a wide range of salinities(15 to 30), but show better growth and survival at relatively low salinities. Thus, it is recommended to use relatively low salinities in hatchery and nursery systems for improved yields of C. hongkongensis.

Modified halloysite nanotubes reduce the toxic effects of zearalenone in gestating sows on growth and muscle development of their offsprings

Background： Zearalenone （ZEN） is an estrogenic mycotoxin that is primarily produced by Fusarium fungi and has been proven to affect the reproductive capacity of many species to varying degrees. The present experiment was designed to study the maternal persistent effects of zearalenone toxicity in gestating sows on growth and muscle development of their offsprings, and the alleviation of zearalenone toxicity by modified halloysite nanotubes （MHNTs）. Methods： Eighteen sows were fed with one of three dietary treatments that included the following： （1） a control diet, （2） a contaminated grain diet （with 50 % moldy corn, 2.77 mg/kg ZEN）, and （3） a contaminated grain diet （with 50 % moldy corn, 2.76 mg/kg ZEN） ＋ 1% MHNTs. Each sow was exclusively fed its experimental diets from 35 to 70 d of gestation at a total of 2 kg daily. Muscle samples were collected from six piglets per treatment at birth, weaning and finishing. Results： The results showed that feeding the sows with the ZEN-contaminated diets from 35 to 70 d of gestation decreased the ADG, ADFI and G：F of their offsprings （P 〈 0.05）. The muscle fiber numbers in the newborn, weaning and growing-finishing pigs and the muscle fiber diameters at birth and weaning were also decreased by maternal ZEN exposure （P 〈 0.05）. The expressions of IGF-I, IGF-II, Myf-5 and Mstn at birth and IGF-II, Pax7, Myf-5 and MyoD1 at weaning were altered by feeding gestating sows with ZEN-contaminated diets （P 〈 0.05）. The MHNTs reduced most of the ZEN-induced toxic effects： the ADG and ADFI on growth performance, the muscle fiber numbers at weaning and finishing and the muscle fiber diameters at weaning （P 〈 0.05）. The expression levels of IGF-II and Mstn in newborn piglets and IGF-II and Myf-5 in weaning piglets were also prevented by adding 1% MHNTs （P 〈 0.05）. Conclusions： The present study demonstrated that the offsprings of sows fed with ZEN-contaminated diets from 35 to 70 day of gestation exhibited weakening on growth performance, physiological changes in their muscle fibers and alterations of mRNA expression in their muscle tissues, and also indicated that MHNTs prevented most of the ZEN- induced weakening in the muscle tissues.

Sequence Variations in the Bovine IGF-I and IGFBP3 Genes and Their Association with Growth and Development Traits in Chinese Beef Cattle

The objective of this study was to determine the genotype effects of the bovine insulin-like growth factor Ⅰ （IGF-Ⅰ） and its binding protein 3 （IGFBP3） genes on growth and development traits in beef cows, including 130 Chinese Simmental, 42 Nanyang, and 47 Luxi Yellow cattle. Sequence variations in the bovine IGF-Ⅰ and IGFBP3 genes were investigated by single strand conformation polymorphism （SSCP）. SSCPs were detected in 6 fragments, which is the 5＇-flanking region, the 2nd exon, the 5th exon, and the 5th intron of the IGF-1 gene, and the 2nd exon, the 3rd exon of the 1GFBP3 gene. Two polymorphisms, an A-to-G transition in the 2rid exon of the IGF-Ⅰ gene and a T-to-C transition in the 2rid exon of IGFBP3 gene were detected in 3 breeds. The allele frequencies of 2 polymorphisms were 0.0411 （A）, 0.9589 （B）, and 0.7237 （A）, 0.2763 （B）, respectively. These 2 loci were analyzed to associate with body weight, height at withers, body length, heart girth, rump width, and beef production index （BPI） at 0, 6, 12, 24, and 36-month old. The IGFBP3 locus was shown to be associated with rump width, heart girth at 24-month and 36-month. Animals with BB genotype had higher rump width （24.86 ± 0.47） cm at 24-month and （27.50 ± 0.63） em at 36-month. The heart girth was highest for the individuals with BB genotype （171.33 ± 1.84） cm and higher than those with AB genotype （166.68 ± 1.13） cm （P〈 0.05） at 36-month.

STUDY ON EMBRYONIC DEVELOPMENT AND EARLY GROWTH OF TRIPLOID AND GYNOGENETIC DIPLOID LEFT-EYED FLOUNDER, PARALICHTHYS OLIVACEUS (T. et S.)

The early effects of chromosomal manipulation of eggs and sperm on the yields of triploid and gynogenetic diploid larvae of Paralichthys olivaceus were investigated. Triploidy was achieved by cold shocking fertilized eggs at 0-2℃ for 45 minutes duration 5 minutes after fertilization, and the induced triploidy rates were 31.2%-50% and the relative hatching rates were 53.3%-99%. Gynogenetic diploids were obtained when eggs were inseminated with irradiated sperm and cold shocked at 0-2℃ for 45 minutes duration 5 minutes after fertilization. The induced gynogenetic diploid rates and the relative hatching rates were 94%-96% and 48.5%-68.5% respectively. The embryonic development of the triploid experimental group and of the gynogenetic diploid experimental group was delayed at first compared with the control group. But from the gastrula stage, it was not delayed anymore. There were no significant differences in the growth of the triploid experimental group larvae and the control group larvae, and in the growth of the gynogenetic diploid experimental group larvae and the control group larvae according to Student’s t test (α=0.05). The relationship between the early growth of the triploid experimental group larvae and that of gynogenetic diploid experimental group larvae was also studied.

Plant growth and their root development after inoculation of arbuscular mycorrhizal fungi in coal mine subsided areas

Coal mining often cause serious land degradation, soil erosion, and desertification affecting growth of the local vegetation, especially the roots. Arbuscular mycorrhizal fungi （AMF） inoculation is considered a potential biotechnological tool for mined soil remediation because mycorrhizal fungi could improve plant growth environment, especially under adverse conditions due to their good symbiosis. A field experiment was conducted to study the ecological effects of AMF （Funneliformis mosseae, Rhizophagus intraradices） on the growth of Amygdalus pedunculata Pall. and their root development in the regenerated mining subsidence sandy land. The reclamation experiment included four treatments： inoculation of Funneliformis mosseae （F.m）, inoculation of Rhizophagus intraradices （R.i）, combined inoculation of F.m and R.i and non-inoculated treatment. Root mycorrhizal colonization, plant height, crown width, soil moisture, root morphology and certain soil properties were assessed. The results showed that AMF improved the shoot and root growth of Amygdalus pedunculata Pall., and significantly increased root colonization after 1 year of inoculation. Available phosphorus content, activities of phosphatase as well as electrical conductivity in soil rhizosphere of all the three inoculation treatments were higher than that of the non-inoculated treatment. AMF increased the quantity of bacteria and fungi in soil rhizosphere compared with the non-inoculated treatment. Our study indicates that revegetation with AMF inoculum could influence plant growth and root development as well as soil properties, suggesting that AMF inoculation can be effective method for further ecological restoration in coal mine subsided areas.