The macropterous individual of Cixiopsis punctatus Matsumura is recognized based on morphological comparison and the mitochondrial COI gene sequences.The pairwise distances among the specimens examined ranged from 0 t...The macropterous individual of Cixiopsis punctatus Matsumura is recognized based on morphological comparison and the mitochondrial COI gene sequences.The pairwise distances among the specimens examined ranged from 0 to 0.0228.Mean distance between macropterous female（Cixiopsis sp.） and 5 brachypterous specimens of Cixiopsis punctatus is 0.0161,which was close enough to consider the macropterous female and brachypterous specimens to be the same species.The external morphology of macropterous female of Cixiopsis punctatus is firstly illustrated and described.展开更多
The lipids was extracted from the internal organs of Ictalurus punctatus by microwave, and its liposoluble chemical constituents was identified and quantified by gas chromatography （GC）/electron impact （EI） mass s...The lipids was extracted from the internal organs of Ictalurus punctatus by microwave, and its liposoluble chemical constituents was identified and quantified by gas chromatography （GC）/electron impact （EI） mass spectrometry （MS）. Subsequent-ly, the acid catalysis method was used to convert fatty acids to methyl-esters. The total lipids in the pure fat of I. punctatus were found to be about 99%. Twenty-three fatty acids were identified. The major fatty acids found in the oils were normal mo-nounsaturated, polyunsaturated fatty acids and alkane paraffin. Unsaturated fatty acids comprised 72.84% of the total, and the major components of monounsaturated fatty acids were C18：1 （48.52%）, while the polyunsaturated fatty acids were mainly composed of C18：2 （16.54%）. Saturated fatty acids comprised approximately 19.21%of the total. The main components were C16：0 （14.46%） and C18：0 （4.17%）, most of which were medium-long-chain fatty acids. Therefore, catfish oil can be used as an important dietary source of functional fatty acids. The difference between the pro-portion of unsaturated and saturated fatty acids appears to be significant compared to fish of the Cyprinidae family, as catfish skin and muscle have higher protein content and lower fatty content. This study confirms that catfish has excellent nutri-tional quality.展开更多
Based on the data of mean population density of overwintering larvae of Dendrolimus punctatus in Shatang forest farm in Guangxi Province, the spatial pattern of overwintering larva of D. punctatus were analyzed by the...Based on the data of mean population density of overwintering larvae of Dendrolimus punctatus in Shatang forest farm in Guangxi Province, the spatial pattern of overwintering larva of D. punctatus were analyzed by the distribution index and regression model method. The results showed that the spatial pattern of overwintering larvae of D. punctatus assumed the aggregation pattern, the basic component of distribution was individual group. The optimal sampling number of forest survey and the sequential sampling analysis were presented, and the upper and low bound index for controlling D. punctatus were put forward to provide certain theoretical basis for integrated pest management.展开更多
Dendroctonus spp. is one of the most portable pests in imported and ex- ported timber and wooden packages, and it is an important object of the port quarantine. Making rapid and accurate identification of Dendroctonus...Dendroctonus spp. is one of the most portable pests in imported and ex- ported timber and wooden packages, and it is an important object of the port quarantine. Making rapid and accurate identification of Dendroctonus spp. is an im- portant method to reduce the invasion risk of Dendroctonus spp. for China. In this paper, Dendroctonus punctatus, which belongs to the Dendroctonus spp., is intro- duced in detail from the aspects of taxonomic status, biological characteristics, mor- phological characteristics and the invasion risk, providing reference for the identifica- tion of Dendroctonus punctatus in inspection and quarantine.展开更多
To detect distribution and relative frequency of diffuse neuroendocrine system （DNES） cells in the gastrointestinal tract of channel catfish （lctalurus punctatus）, the intestinal tract of channel catfish was divid...To detect distribution and relative frequency of diffuse neuroendocrine system （DNES） cells in the gastrointestinal tract of channel catfish （lctalurus punctatus）, the intestinal tract of channel catfish was divided into seven portions from proximal to distal： the enlarged area after oesophagus, cardia, fundus, pylorus, and anterior, middle, and posterior intestine. Immunohistochemical method using the strept avidin-biotin-complex （SABC） was employed. All antisera between seven portions of the channel catfish were compared statistically using statistical package for the social science （SPSS）. Five types of DNES ceils were determined： neuropeptide Y-immunoreactive （NPY-IR） cells were demonstrated in both anterior and middle intestine; serotonin （5-HT） immunoreactive cells were detected throughout the whole gastrointestinal tract; vasoactive intestinal peptide （VIP） positive cells were at the highest frequency in pylorus; glucagon-immunoreactive （GLU-IR） cells were moderate in number in the fundus and anterior, middle intestine, and no immunoreactivity was determined in the other portions; somatostatin （SOM） positive cells were more abundant in the anterior and middle intestine. The regional distribution and relative frequency of immunoreactive cells in the channel catfish, Ictalurus punctatus, are essentially similar to those of other fish. However, some characteristics are observed in this species, which further proved that the diversity of the physiological function of DNES cells was based on their morphology.展开更多
[Objective] The paper was to establish prediction model for Dendrolimus punctatus Walker in coastal shelterbeh in Zhejiang Province of China. [ Method] Using the principles and methods of SAS software, and according t...[Objective] The paper was to establish prediction model for Dendrolimus punctatus Walker in coastal shelterbeh in Zhejiang Province of China. [ Method] Using the principles and methods of SAS software, and according to the correlation analysis and stepwise regression analysis, we selected the relevant meteorological factors from April 1982 to March 2006 as the variables and the population density of D. punctatus from 1983 to 2006 as the dependent variables, to establish the prediction model between insect population density and meteorological factors for D. punctatas in coastal shelterbelt. [ Result] By fitting test, the his- torical compliance rate of the equation was above 85%. When the related data from 2007 to 2011 were used for prediction test, the occurrence condition had small relative error with prediction results except the years seriously affected by natural disasters. [ Conclusion] The paper provides certain reference for pest control against D. punctatus in coastal shelterbelt.展开更多
In recent years,Konosirus punctatus has accounted for a large portion in catch composition and become important economic species in the South Yellow Sea.However,the distribution of K.punctatus early life stages is sti...In recent years,Konosirus punctatus has accounted for a large portion in catch composition and become important economic species in the South Yellow Sea.However,the distribution of K.punctatus early life stages is still poorly understood.In this study,generalized additive models with Tweedie distribution were used to analyze the relationships between K.punctatus ichthyoplankton and environmental factors(longitude and latitude,sea surface temperature(SST),sea surface salinity(SSS)and depth),and predict distribution K.punctatus spawning ground and nursing ground,based on samplings collected in 6 months during 2014–2017.The results showed that K.punctatus’spawning ground were mainly distributed in central and north study area(from 33.0°N to 37.0°N).By comparison,the nursing ground shifted southward,which were approximately located along central and south coast of study area(from 31.7°N to 35.5°N).The optimal models identified that suitable SST,SSS and depth for eggs were 19–26℃,25–30 and 9–23 m,respectively.The suitable SSS for larvae were 29–31.The K.punctatus spawning habit might have changed in the past decades,which was a response to increasing SST and fishing pressure.That needs to be proved in further study.The study provides references of conservation and exploitation for K.punctatus.展开更多
Phenol, a ubiquitous component of industrial effluents, is a common pollutant of water resources and a serious threat to fish.The present work demonstrates that a significant amount of phenol is retained by various ti...Phenol, a ubiquitous component of industrial effluents, is a common pollutant of water resources and a serious threat to fish.The present work demonstrates that a significant amount of phenol is retained by various tissues of the common carp.Cyprinus carpio.and the snake-headed murrel.Channa punclatus.The rate of [^(14)C] phenol accumulation was higher in the carp than in the murrel.It is suggested that retention of phenol in the brain and ovary may seriously afiect the reproductive potential of the fish. 1990 Academic Press.Inc.展开更多
With regard to brain acetylcholinesterase and acetylcholine and serum triiodothyronine(T_3) and thyroxine(T_4)profiles,a biphasic response pattern was elicited in Channa punctatus chroni- cally exposed to nonlethal do...With regard to brain acetylcholinesterase and acetylcholine and serum triiodothyronine(T_3) and thyroxine(T_4)profiles,a biphasic response pattern was elicited in Channa punctatus chroni- cally exposed to nonlethal doses of locally used pesticides,namely,Metacid-50 and Carbaryl. Data revealed that these xenobiotics caused significant inhibition of brain acetylcholinesterase activity and a decrease in thyroxine level accompanied by a concurrent increase in acetylcholine accumulation and T_3 level.It is surmised that Metacid-50 and Carbaryl influence both neural and hormonal functions.1989 Academic Press.Inc.展开更多
The aim of this study is to assess the adverse effects of lead, a well-documented non-essential element that occurs naturally in the environment, on Channa punctatus, in relation with ROS production and oxidative stre...The aim of this study is to assess the adverse effects of lead, a well-documented non-essential element that occurs naturally in the environment, on Channa punctatus, in relation with ROS production and oxidative stress. Fishes were sampled, acclimatized and kept treated or untreated with lead (9.43 mg/L) under observation for 4 days. At day 4, respiratory burst activity, lipid peroxidation activity and superoxide dismutase level increased significantly in treated group as compared to the control. On the contrary, catalase, glutathione S-transferase, glutathione peroxidase, glutathione reductase and reduced glutathione activity decreased on treatment with lead. These results suggest that heavy metal like lead induces oxidative stress, influences the antioxidant defense system and may lead to physiological disorders rendering the health and survival of exposed fish to a compromised state.展开更多
Objective:To study the incidence of encysted progenetic metacercariae of Clinostomum complanatum(C. complanatum) in Channa punctatus(C. punctatus), associated histopathology and the experimental infection to laborator...Objective:To study the incidence of encysted progenetic metacercariae of Clinostomum complanatum(C. complanatum) in Channa punctatus(C. punctatus), associated histopathology and the experimental infection to laboratory chicken to obtain ovigerous adult worms.Methods:Live C. punctatus were brought from local fish market of Aligarh, India, dissected and examined on a monthly basis for the presence of C. complanatumcysts. For histochemistry, infected tissue sections with attached cysts were processed for haematoxylene and eosin staining. Cysts were aseptically fed to 4 day old leghorn chicken to obtain adult worms. Mechanically excysted metacercaria and the ovigerous adult worms were stained in carmine to prepare permanent slides.Results:One year survey for the infection of encysted progenetic metacercaria of C.complanatuminC. punctatusrevealed the prevalence, intensity and abundance of 24.7%, 2.27and 0.608, respectively. Histopathology showed heavy infiltration of immune cells at the site of cyst attachment and some tissue damage was also evident. Following feeding to experimental chicken, about 41.07% of the encysted metacercariae were able to excyst and migrate back to bucco-pharyngeal region where they tenaciously attached and fed on blood, and transformed into ovigerous adult worms from 62 hours onwards of post infection.Conclusions:The parasite is potentially pathogenic to the host, and the availability of a suitable intermediate host can be a contributing factor for the occurrence of C. complanatummetacercaria either in the excysted or encysted form, indicating loose host specificity and zoonotic potential.展开更多
Insects with their ecological superpower have enormous capacity to transform small pollution damage in forests to full scale calamities. Acid rain resulting from extensive coal burning is the chief pollutant in China....Insects with their ecological superpower have enormous capacity to transform small pollution damage in forests to full scale calamities. Acid rain resulting from extensive coal burning is the chief pollutant in China. Acid rain activates from soil deposits toxic metals, which are transferred to trees and further to insects eating them. We studied the levels of the toxic Cd, its antagonists Zn and Cu, and acid rain indicators Fe and Mn in the forest pest moth Dendrolimus punctatus Walker (Lepidoptera:Lasiocampidae) in variously polluted Pinus massoniana Lamb forests in China.\; The highest density of D. punctatus , as well as the highest Cd levels developed in the moderately polluted forests. Possibly Cd had there broken down the pest resistance of the pines. The paradoxical coexistence of high Cd level and elevated population density of the pest seems to result from the high accumulation of Cd in its ichneumonid parasitoid. In the most heavily polluted forests the Cd level in needles was low, possibly because the strong acid rain had washed away most of the Cd deposit in the soil. It existed there no D.punctatus population. Absence of pest insects from the most heavily polluted areas is a common phenomenon.展开更多
Three ponds with the areas of 800, 1 000 and 1 000 m2 were settled in Yambajan aquaculture base for rearing test of Ictalurus punctatus in plateau zone. The results showed that as 30 000 fries were released, 19 830 fi...Three ponds with the areas of 800, 1 000 and 1 000 m2 were settled in Yambajan aquaculture base for rearing test of Ictalurus punctatus in plateau zone. The results showed that as 30 000 fries were released, 19 830 fingerlings of 1. punctatus were obtained after 270 d rearing, with the average body length of 21.2 cm, the average body weight of 216.5 g, the survival rate of 66.1%, and the fingerling harvest of 4 293.2 kg. Thus, it is effective and feasible to rear I. punctatus with residual heat resources of power plants in cold plateau zone.展开更多
Objective The putative coronatean Punctatus flourished at the beginning of the Cambrian explosion, and is significant in the exploration of the origin and evolution of early life. Liu Yunhuan established a new specie...Objective The putative coronatean Punctatus flourished at the beginning of the Cambrian explosion, and is significant in the exploration of the origin and evolution of early life. Liu Yunhuan established a new species： Punctatus triangulicostalis Liu, 2006. Two questions remain： how was the special body plan of P. triangulicostalis formed？ How does P. triangulicostalis transform from embryo to the long cylindrical mature individual？ Although the study of Steiner et al. in 2004 involved the above questions, they did not explain them clearly due to the lack of fossil materials at that time. This article aims to consider the above questions based on new information from several rare specimens.展开更多
Regulation of gonadal function by gonadotropic hormone (GtH) and gonadotropin-releasing hormone (GnRH) in Channa punctatus was significantly affected by nonlethal levels of Metacid-50 and Carbaryl. Under laboratory co...Regulation of gonadal function by gonadotropic hormone (GtH) and gonadotropin-releasing hormone (GnRH) in Channa punctatus was significantly affected by nonlethal levels of Metacid-50 and Carbaryl. Under laboratory conditions, the time-dependent decrease in serum GtH level was higher in Carbaryl-treated fish than in Metacid-50-treated fish. The situation was reversed in the field, with a higher inhibitory effect of Metacid-50 being recorded. On the other hand, pituitary GtH content and GnRH activity were inhibited to a greater extent by Metacid-50 than by Carbaryl under both field and laboratory conditions. The present findings highlight that even low doses of Metacid-50 and Carbaryl are effective enough to cause reproductive damage, as evidenced by homeostatic unbalance of the reproductive regulatory system. 1990 Academic Press. Inc.展开更多
基金supported by the National Science Foundation of China(30970387,31172126)
文摘The macropterous individual of Cixiopsis punctatus Matsumura is recognized based on morphological comparison and the mitochondrial COI gene sequences.The pairwise distances among the specimens examined ranged from 0 to 0.0228.Mean distance between macropterous female（Cixiopsis sp.） and 5 brachypterous specimens of Cixiopsis punctatus is 0.0161,which was close enough to consider the macropterous female and brachypterous specimens to be the same species.The external morphology of macropterous female of Cixiopsis punctatus is firstly illustrated and described.
基金Supported by a grant from Hunan Provincial Science and Technology Department(2010SK303)a grant from Jishou University(JDSTLY201110)The National Small and Mid-sized Enterprise Technology Innovation Fund(12C26214304972)~~
文摘The lipids was extracted from the internal organs of Ictalurus punctatus by microwave, and its liposoluble chemical constituents was identified and quantified by gas chromatography （GC）/electron impact （EI） mass spectrometry （MS）. Subsequent-ly, the acid catalysis method was used to convert fatty acids to methyl-esters. The total lipids in the pure fat of I. punctatus were found to be about 99%. Twenty-three fatty acids were identified. The major fatty acids found in the oils were normal mo-nounsaturated, polyunsaturated fatty acids and alkane paraffin. Unsaturated fatty acids comprised 72.84% of the total, and the major components of monounsaturated fatty acids were C18：1 （48.52%）, while the polyunsaturated fatty acids were mainly composed of C18：2 （16.54%）. Saturated fatty acids comprised approximately 19.21%of the total. The main components were C16：0 （14.46%） and C18：0 （4.17%）, most of which were medium-long-chain fatty acids. Therefore, catfish oil can be used as an important dietary source of functional fatty acids. The difference between the pro-portion of unsaturated and saturated fatty acids appears to be significant compared to fish of the Cyprinidae family, as catfish skin and muscle have higher protein content and lower fatty content. This study confirms that catfish has excellent nutri-tional quality.
基金Supported by Fund Project in Guangxi Eco-engineering Vocational&Technical College~~
文摘Based on the data of mean population density of overwintering larvae of Dendrolimus punctatus in Shatang forest farm in Guangxi Province, the spatial pattern of overwintering larva of D. punctatus were analyzed by the distribution index and regression model method. The results showed that the spatial pattern of overwintering larvae of D. punctatus assumed the aggregation pattern, the basic component of distribution was individual group. The optimal sampling number of forest survey and the sequential sampling analysis were presented, and the upper and low bound index for controlling D. punctatus were put forward to provide certain theoretical basis for integrated pest management.
基金Supported by Quarantine Industry Research Special Funds for Public Welfare Projects(201310075-2)Research Project of General Administration of Quality Supervision,Inspection and Quarantine(2012IK276)Changzhou Science and Technology Project(CJ20120027,CJ20130036)~~
文摘Dendroctonus spp. is one of the most portable pests in imported and ex- ported timber and wooden packages, and it is an important object of the port quarantine. Making rapid and accurate identification of Dendroctonus spp. is an im- portant method to reduce the invasion risk of Dendroctonus spp. for China. In this paper, Dendroctonus punctatus, which belongs to the Dendroctonus spp., is intro- duced in detail from the aspects of taxonomic status, biological characteristics, mor- phological characteristics and the invasion risk, providing reference for the identifica- tion of Dendroctonus punctatus in inspection and quarantine.
基金supported by the Special Founda-tion for Young Leaders Fellowship in the Sichuan Agri-cultural University, China (45078925-5).
文摘To detect distribution and relative frequency of diffuse neuroendocrine system （DNES） cells in the gastrointestinal tract of channel catfish （lctalurus punctatus）, the intestinal tract of channel catfish was divided into seven portions from proximal to distal： the enlarged area after oesophagus, cardia, fundus, pylorus, and anterior, middle, and posterior intestine. Immunohistochemical method using the strept avidin-biotin-complex （SABC） was employed. All antisera between seven portions of the channel catfish were compared statistically using statistical package for the social science （SPSS）. Five types of DNES ceils were determined： neuropeptide Y-immunoreactive （NPY-IR） cells were demonstrated in both anterior and middle intestine; serotonin （5-HT） immunoreactive cells were detected throughout the whole gastrointestinal tract; vasoactive intestinal peptide （VIP） positive cells were at the highest frequency in pylorus; glucagon-immunoreactive （GLU-IR） cells were moderate in number in the fundus and anterior, middle intestine, and no immunoreactivity was determined in the other portions; somatostatin （SOM） positive cells were more abundant in the anterior and middle intestine. The regional distribution and relative frequency of immunoreactive cells in the channel catfish, Ictalurus punctatus, are essentially similar to those of other fish. However, some characteristics are observed in this species, which further proved that the diversity of the physiological function of DNES cells was based on their morphology.
基金Supported by Key Agriculture Project in Major Scientific and Technological Special of Science and Technology Department of Zhejiang Province(2010C12029)
文摘[Objective] The paper was to establish prediction model for Dendrolimus punctatus Walker in coastal shelterbeh in Zhejiang Province of China. [ Method] Using the principles and methods of SAS software, and according to the correlation analysis and stepwise regression analysis, we selected the relevant meteorological factors from April 1982 to March 2006 as the variables and the population density of D. punctatus from 1983 to 2006 as the dependent variables, to establish the prediction model between insect population density and meteorological factors for D. punctatas in coastal shelterbelt. [ Result] By fitting test, the his- torical compliance rate of the equation was above 85%. When the related data from 2007 to 2011 were used for prediction test, the occurrence condition had small relative error with prediction results except the years seriously affected by natural disasters. [ Conclusion] The paper provides certain reference for pest control against D. punctatus in coastal shelterbelt.
基金The Public Science and Technology Research Funds Projects of Ocean under contract No.201305030the National Natural Science Foundation of China under contract No.41930535。
文摘In recent years,Konosirus punctatus has accounted for a large portion in catch composition and become important economic species in the South Yellow Sea.However,the distribution of K.punctatus early life stages is still poorly understood.In this study,generalized additive models with Tweedie distribution were used to analyze the relationships between K.punctatus ichthyoplankton and environmental factors(longitude and latitude,sea surface temperature(SST),sea surface salinity(SSS)and depth),and predict distribution K.punctatus spawning ground and nursing ground,based on samplings collected in 6 months during 2014–2017.The results showed that K.punctatus’spawning ground were mainly distributed in central and north study area(from 33.0°N to 37.0°N).By comparison,the nursing ground shifted southward,which were approximately located along central and south coast of study area(from 31.7°N to 35.5°N).The optimal models identified that suitable SST,SSS and depth for eggs were 19–26℃,25–30 and 9–23 m,respectively.The suitable SSS for larvae were 29–31.The K.punctatus spawning habit might have changed in the past decades,which was a response to increasing SST and fishing pressure.That needs to be proved in further study.The study provides references of conservation and exploitation for K.punctatus.
文摘Phenol, a ubiquitous component of industrial effluents, is a common pollutant of water resources and a serious threat to fish.The present work demonstrates that a significant amount of phenol is retained by various tissues of the common carp.Cyprinus carpio.and the snake-headed murrel.Channa punclatus.The rate of [^(14)C] phenol accumulation was higher in the carp than in the murrel.It is suggested that retention of phenol in the brain and ovary may seriously afiect the reproductive potential of the fish. 1990 Academic Press.Inc.
文摘With regard to brain acetylcholinesterase and acetylcholine and serum triiodothyronine(T_3) and thyroxine(T_4)profiles,a biphasic response pattern was elicited in Channa punctatus chroni- cally exposed to nonlethal doses of locally used pesticides,namely,Metacid-50 and Carbaryl. Data revealed that these xenobiotics caused significant inhibition of brain acetylcholinesterase activity and a decrease in thyroxine level accompanied by a concurrent increase in acetylcholine accumulation and T_3 level.It is surmised that Metacid-50 and Carbaryl influence both neural and hormonal functions.1989 Academic Press.Inc.
文摘The aim of this study is to assess the adverse effects of lead, a well-documented non-essential element that occurs naturally in the environment, on Channa punctatus, in relation with ROS production and oxidative stress. Fishes were sampled, acclimatized and kept treated or untreated with lead (9.43 mg/L) under observation for 4 days. At day 4, respiratory burst activity, lipid peroxidation activity and superoxide dismutase level increased significantly in treated group as compared to the control. On the contrary, catalase, glutathione S-transferase, glutathione peroxidase, glutathione reductase and reduced glutathione activity decreased on treatment with lead. These results suggest that heavy metal like lead induces oxidative stress, influences the antioxidant defense system and may lead to physiological disorders rendering the health and survival of exposed fish to a compromised state.
基金financially supported by Aligarh Muslim University(grant No.09PHDL128)
文摘Objective:To study the incidence of encysted progenetic metacercariae of Clinostomum complanatum(C. complanatum) in Channa punctatus(C. punctatus), associated histopathology and the experimental infection to laboratory chicken to obtain ovigerous adult worms.Methods:Live C. punctatus were brought from local fish market of Aligarh, India, dissected and examined on a monthly basis for the presence of C. complanatumcysts. For histochemistry, infected tissue sections with attached cysts were processed for haematoxylene and eosin staining. Cysts were aseptically fed to 4 day old leghorn chicken to obtain adult worms. Mechanically excysted metacercaria and the ovigerous adult worms were stained in carmine to prepare permanent slides.Results:One year survey for the infection of encysted progenetic metacercaria of C.complanatuminC. punctatusrevealed the prevalence, intensity and abundance of 24.7%, 2.27and 0.608, respectively. Histopathology showed heavy infiltration of immune cells at the site of cyst attachment and some tissue damage was also evident. Following feeding to experimental chicken, about 41.07% of the encysted metacercariae were able to excyst and migrate back to bucco-pharyngeal region where they tenaciously attached and fed on blood, and transformed into ovigerous adult worms from 62 hours onwards of post infection.Conclusions:The parasite is potentially pathogenic to the host, and the availability of a suitable intermediate host can be a contributing factor for the occurrence of C. complanatummetacercaria either in the excysted or encysted form, indicating loose host specificity and zoonotic potential.
文摘Insects with their ecological superpower have enormous capacity to transform small pollution damage in forests to full scale calamities. Acid rain resulting from extensive coal burning is the chief pollutant in China. Acid rain activates from soil deposits toxic metals, which are transferred to trees and further to insects eating them. We studied the levels of the toxic Cd, its antagonists Zn and Cu, and acid rain indicators Fe and Mn in the forest pest moth Dendrolimus punctatus Walker (Lepidoptera:Lasiocampidae) in variously polluted Pinus massoniana Lamb forests in China.\; The highest density of D. punctatus , as well as the highest Cd levels developed in the moderately polluted forests. Possibly Cd had there broken down the pest resistance of the pines. The paradoxical coexistence of high Cd level and elevated population density of the pest seems to result from the high accumulation of Cd in its ichneumonid parasitoid. In the most heavily polluted forests the Cd level in needles was low, possibly because the strong acid rain had washed away most of the Cd deposit in the soil. It existed there no D.punctatus population. Absence of pest insects from the most heavily polluted areas is a common phenomenon.
文摘Three ponds with the areas of 800, 1 000 and 1 000 m2 were settled in Yambajan aquaculture base for rearing test of Ictalurus punctatus in plateau zone. The results showed that as 30 000 fries were released, 19 830 fingerlings of 1. punctatus were obtained after 270 d rearing, with the average body length of 21.2 cm, the average body weight of 216.5 g, the survival rate of 66.1%, and the fingerling harvest of 4 293.2 kg. Thus, it is effective and feasible to rear I. punctatus with residual heat resources of power plants in cold plateau zone.
基金supported by the National Natural Science Foundation of China (grant No.41572009)the State Key Laboratory of Palaeobiology and Stratigraphy (grant No.173121)the College Students’ Training Program of Chang’an University (201610710047, 201710710062, 201710710063, 201710710240)
文摘Objective The putative coronatean Punctatus flourished at the beginning of the Cambrian explosion, and is significant in the exploration of the origin and evolution of early life. Liu Yunhuan established a new species： Punctatus triangulicostalis Liu, 2006. Two questions remain： how was the special body plan of P. triangulicostalis formed？ How does P. triangulicostalis transform from embryo to the long cylindrical mature individual？ Although the study of Steiner et al. in 2004 involved the above questions, they did not explain them clearly due to the lack of fossil materials at that time. This article aims to consider the above questions based on new information from several rare specimens.
文摘Regulation of gonadal function by gonadotropic hormone (GtH) and gonadotropin-releasing hormone (GnRH) in Channa punctatus was significantly affected by nonlethal levels of Metacid-50 and Carbaryl. Under laboratory conditions, the time-dependent decrease in serum GtH level was higher in Carbaryl-treated fish than in Metacid-50-treated fish. The situation was reversed in the field, with a higher inhibitory effect of Metacid-50 being recorded. On the other hand, pituitary GtH content and GnRH activity were inhibited to a greater extent by Metacid-50 than by Carbaryl under both field and laboratory conditions. The present findings highlight that even low doses of Metacid-50 and Carbaryl are effective enough to cause reproductive damage, as evidenced by homeostatic unbalance of the reproductive regulatory system. 1990 Academic Press. Inc.
