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Tissue distribution of cadmium and its effect on reproduction in Spodoptera exigua
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作者 Honghua Su Menglu Wu +3 位作者 Yong Yang Yan Deng Yizhong Yang Qingming Sun 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期195-204,共10页
Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua... Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua exposed to cadmium and its effects on the growth and development of the parents and the offspring were investigated.Under the stress of different concentrations of cadmium(0.2,3.2,and 51.2 mg kg^(-1)),the cadmium content in each tissue of S.exigua increased in a dose-dependent manner.At the larval stage,the highest cadmium accumulation was found in midgut in all three cadmium treatments,but at the adult stage,the highest cadmium content was found in fat body.In addition,the cadmium content in ovaries was much higher than in testes.When F1S.exigua was stressed by cadmium and the F_(2)generation was not fed a cadmium-containing diet,the larval survival,pupation rate,emergence rate and fecundity of the F_(2)generation were significantly reduced in the 51.2 mg kg^(-1)treatment compared to the corresponding F1generation.Even in the F_(2)generation of the 3.2 mg kg^(-1)treatment,the fecundity was significantly lower than in the parental generation.The fecundity of the only-female stressed treatment was significantly lower than that of the only-male stressed treatment at the 3.2 and 51.2 mg kg^(-1)cadmium exposure levels.When only mothers were stressed at the larval stage,the fecundity of the F_(2)generation was significantly lower than that of the F1generation in the 51.2 mg kg^(-1)treatment,and it was also significantly lower than in the 3.2 and 0.2 mg kg^(-1)treatments.The results of our study can provide useful information for forecasting the population increase trends under different heavy metal stress conditions and for the reliable environmental risk assessment of heavy metal pollution. 展开更多
关键词 heavy metal pollution CADMIUM Spodoptera exigua tissue distribution reproduction
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Sex-specific facilitation and reproduction of the gynodioecious cushion plant Arenaria polytrichoides on the Himalaya-Hengduan mountains,SW China
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作者 Xufang Chen Yazhou Zhang +3 位作者 Lishen Qian Renyu Zhou Hang Sun Jianguo Chen 《Plant Diversity》 SCIE CAS CSCD 2024年第2期247-255,共9页
When benefiting other beneficiaries,cushion plants may reciprocally receive feedback effects.The feedback effects on different sex morphs,however,remains unclear.In this study,taking the gynodioecious Arenaria polytri... When benefiting other beneficiaries,cushion plants may reciprocally receive feedback effects.The feedback effects on different sex morphs,however,remains unclear.In this study,taking the gynodioecious Arenaria polytrichiodes as a model species,we aimed to assess the sex-specific facilitation intensity of cushion plant by measuring the beneficiary cover ratio,and to assess the potential costs in cushion reproductive functions by measuring the flower and fruit cover ratios.The total beneficiary cover ratio was similar between females and hermaphrodites.Females produced much less flowers but more fruits than hermaphrodites.These results suggested that females and hermaphrodites possess similar facilitation intensity,and female cushion A.polytrichoides may allocate more resources saved from pollen production to seed production,while hermaphrodites possibly allocate more resources to pollen production hence reducing seed production.The surface areas covered by beneficiaries produced less flowers and fruits than areas without beneficiaries.In addition,strong negative correlations between beneficiary cover and flower cover were detected for both females and hermaphrodites,but the correlation strength were similar for these two sex morphs.However,the correlation between beneficiary cover and fruit cover was only significantly negative for females,suggesting that beneficiary plants negatively affect fruit reproduction of females while have neutral effects on hermaphrodites.All the results suggest that to facilitate other beneficiaries can induce reproductive costs on cushion A.polytrichoides,with females possibly suffering greater cost than hermaphrodites.Such differentiation in reproductive costs between sex morphs,in long-term perspective,may imply sex imbalance in population dynamics. 展开更多
关键词 Facilitation intensity Feedback effect Sex-specific facilitation Nurse plant Population dynamics Reproductive function
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Scale Breeding and Reproduction Technique of Ficus tikoua Bur.Container Seedlings
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作者 Tinghong TAN Fan GAO +5 位作者 Yang XIAO Mingxing DAI Shunping BAI Shimei LIAO Chaojun FENG Chunfang WU 《Plant Diseases and Pests》 CAS 2023年第5期16-18,23,共4页
Based on the principle of asexual reproduction,a kind of scale breeding and reproduction technique of Ficus tikoua Bur.container seedlings was explored by using the characteristics of strong adaptability to the enviro... Based on the principle of asexual reproduction,a kind of scale breeding and reproduction technique of Ficus tikoua Bur.container seedlings was explored by using the characteristics of strong adaptability to the environment and fast growth and reproduction.Using non-woven bag as a breeding container for seedlings,the scale breeding and reproduction technique of F.tikoua container seedlings was summarized through the important links of seedling bed construction,seedling collection,soil configuration,container selection,cutting cultivation,field management,and disease and pest control.This technique can achieve differential,massive and sustainable efficient breeding and reproduction of F.tikoua seedlings in a short time. 展开更多
关键词 Ficus tikoua Bur Pharmaceutical/food resource Asexual reproduction Container seedling Scale breeding and reproduction
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EcR/USP-1-mediated ecdysteroid signaling regulates wolf spider(Pardosa pseudoannulata) development and reproduction
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作者 Zhi-Ming Yang Yang-Yang Yan +2 位作者 Yong Wu Na Yu Ze-Wen Liu 《Zoological Research》 SCIE CAS CSCD 2023年第1期43-52,共10页
Lycosidae females demonstrate meticulous maternal care of offspring by carrying egg sacs and juvenile spiderlings during the reproductive stage. Nuclear receptors(NRs), especially the ecdysone receptor(EcR) and ultras... Lycosidae females demonstrate meticulous maternal care of offspring by carrying egg sacs and juvenile spiderlings during the reproductive stage. Nuclear receptors(NRs), especially the ecdysone receptor(EcR) and ultraspiracle(USP), have attracted considerable attention in the regulation of arthropod development and reproduction due to their pivotal roles in ecdysteroid signaling cascades. In the present study, 23 NRs, including one EcR and two USPs, were identified in the genome of the predatory wolf spider Pardosa pseudoannulata. RNA interference(RNAi) targeting EcR and USP-1inhibited spiderling development and resulted in nonviable eggs in the egg sacs. EcR and USP-1responded to changes in ecdysteroid levels, and interference in ecdysteroid biosynthesis led to similar phenotypes as ds EcR and ds USP-1 treatments.These findings suggest that EcR/USP-1-mediated ecdysteroid signaling regulates P. pseudoannulata development and reproduction. The P.pseudoannulata females with suppressed ecdysteroid signaling proactively consumed their non-viable egg sacs, resulting in a 7.19 d shorter first reproductive cycle than the controls. Termination of the failed reproductive cycle enabled the spiders to produce a new egg sac more rapidly. This reproductive strategy may partially rescue the reduction in population growth due to non-viable eggs and compensate for the physiological expenditure of wasted maternal care, which would be beneficial for the conservation of P.pseudoannulata populations and their natural control of insect pests. 展开更多
关键词 Pardosa pseudoannulata Ecdysone receptor ULTRASPIRACLE DEVELOPMENT reproduction
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Performance in Survival,Development and Reproduction of Aphis glycines Matsumura Virginoparae at High Temperatures
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作者 Liu Jian Liu Zhe +3 位作者 Wu Ci-rui Liu Dai-lin Huo Dong-bo Sun Wen-peng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2023年第1期20-27,共8页
The soybean aphid,Aphis glycines Matsumura,is an important pest of soybean,which is native to Asia.In this study,A.glycines fed on soybean(AgFS)and A.glycines fed on wild soybean(AgFW)were reared at 25℃,27℃,29℃,31... The soybean aphid,Aphis glycines Matsumura,is an important pest of soybean,which is native to Asia.In this study,A.glycines fed on soybean(AgFS)and A.glycines fed on wild soybean(AgFW)were reared at 25℃,27℃,29℃,31℃,33℃and 35℃,respectively,and some of the life parameters were determined.At temperature ranging from 25℃to 31℃,nymphs of AgFS and AgFW all developed into adults successfully.Only a few nymphs of AgFS and AgFW developed into adults at 33℃and no nymphs could develop into adults at 35℃.Lifespan,fecundity and body size of AgFS and AgFW adults all decreased gradually with temperatures increasing from 25℃to 33℃.At 25℃,the intrinsic rate of increase of AgFS was as big as that at 27℃,which was smaller than that at 29℃,but was bigger than that at 31℃.Intrinsic rate of increase of AgFW decreased gradually with temperatures increasing from 25℃to 31℃.Nymph stage duration of AgFW was longer than or as long as that of AgFS;adult lifespan of AgFW was shorter than or as long as that of AgFS.Adult fecundity,intrinsic rate of increase and adult body size of AgFW were all smaller than or as big as those of AgFS.It showed that AgFS and AgFW both survived and developed well at temperature ranging from 25℃to 31℃,and AgFW was more adaptive to low temperatures.These results were important to study the adaptability of A.glycines to high temperatures and for predicting its dynamics in the temperature keeping rising region. 展开更多
关键词 Aphis glycines Matsumura DEVELOPMENT reproduction high temperature
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Effects of Different Levels of Garlic Powder Incorporated in the Feed Enriched with Stylosanthes guianensis on Reproduction and Pre-Weaning Growth Performances of Cavies (Cavia porcellus)
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作者 Martin Vidal Tatang Emile Miégoué +6 位作者 Margaret Mary Momo Chongsi Wouafo David Fokom Nyah Cédric Kwayep Paulette Ntsafack Tobou France-Gina Djoumessi Mathieu Duclos Fogang Fernand Tendonkeng 《Open Journal of Animal Sciences》 2023年第4期574-589,共16页
In order to increase the productivity of the local cavies as a meat animal, a study was carried out between November 2021 and March 2022 at the Research and Experimental Farm, Animal Nutrition and Production Research ... In order to increase the productivity of the local cavies as a meat animal, a study was carried out between November 2021 and March 2022 at the Research and Experimental Farm, Animal Nutrition and Production Research Unit of the Faculty of Agronomy and Agricultural Sciences (FAAS) and the Microbiology and Anti-Microbial Research Unite of the University of Dschang on 72 cavies aged between 4 and 5 months and weighing an average of 450 ± 50 g produced on the farm, including 60 females and 12 males. The females were distributed according to a completely randomized factorial design in twelve (12) rearing boxes numbered G1 to G12, with 15 females per group distributed in 03 boxes and receiving iso-nitrogenated experimental diet (18% protein) R0 enriched with 20% of Stylosanthes guianensis (0% garlic powder), R0.25 (0.25% garlic powder), R0.50 (0.50% garlic powder) and R0.75 (0.75% garlic powder). Females were identified by numbered ear tags and mated with a sex ratio of 5 females for 1 male. Drinking water enriched with vitamin C (01 tablet of 240 mg in 1.5 liters of water) was served ad libitum and renewed daily. The males were removed after 31 days. A form was established to record the weight of each pregnant female, any abortions during gestation, the date of parturition and the date of birth of each newborn, as well as the number of live-born or stillborn pups. After parturition, the weights of female and newborn cavies were recorded weekly until the 3<sup>rd</sup> week. The number of cavies that died before weaning and the number of live weaned cavies were also recorded. Reproductive performance significantly increased (p 0.05) fertility rate and net fertility rate, litter size, birth viability rate, and pre-weaning viability rate with rations containing garlic powder, compared to the control ration, especially with the R0.50 ration. In addition, birth mortality and pre-weaning mortality were significantly lower (p 0.05) with rations containing the additive, compared to those of the control ration (R0). However, the R0.50 ration showed the lowest rates, followed by the R0.25 ration, and finally the R0.75 ration. Weight development of young cavies increased with all rations but was more marked with the R0.50 ration. Only total weight gain (TG) and average daily weight gain (ADG) in the pre-weaning phase were significantly increased (p < 0.05) with rations R0.25 and R0.50. 展开更多
关键词 Cavy Garlic Powder Pre-Weaning Growth reproduction Stylosanthes guianensis
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Russian Collaborative Development of Reproduction Technologies for the Sustainable Management of Amphibian Biodiversity
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作者 Victor K.UTESHEV Edith N.GAKHOVA +5 位作者 Ludmila I.KRAMAROVA Natalia V.SHISHOVA Svetlana A.KAUROVA Elena A.KIDOVA Artem A.KIDOV Robert K.BROWNE 《Asian Herpetological Research》 SCIE CSCD 2023年第1期103-115,共13页
Reproduction technologies(RTs)can provide for the reliable reproduction of amphibians,as well as perpetuation of species genetic variation with the use of biobanks.In 1982,in anticipation of the biodiversity conservat... Reproduction technologies(RTs)can provide for the reliable reproduction of amphibians,as well as perpetuation of species genetic variation with the use of biobanks.In 1982,in anticipation of the biodiversity conservation crisis,major Russian institutions collaborated in a dynamic program to develop and implement RTs for the sustainable management of amphibian biodiversity.An initial primary focus was the captive breeding of threatened Russian endemic anuran and caudate species,using RTs that varied from environmental manipulation to the use of exogenous gonadotropic hormones to stimulate reproduction.These species were mostly from Palearctic or cool mountain regions,but also included a wide range of species from warm regions.Other early achievements included the successful cryopreservation of anuran spermatozoa and anuran diploid pluripotent cell nuclei,in order to store both the matrilineal and patrilineal genomes in biobanks,with their subsequent development to the blastula stage after implantation into enucleated oocytes.After the turn of the 21st Century,in support of the priorities of the Amphibian Conservation Action Plan(2007),we developed RTs for the refrigerated storage of testicular or urinary spermatozoa for days to weeks at 4℃,the cryopreservation of urinary spermatozoa using anovel cryoprotectant,the in vitro fertilisation of hormonally induced oocytes either fresh or after refrigerated ex situ or in situ storage,and the artificial insemination of salamanders with fresh spermatozoa.In this article,we describe previously unpublished techniques and techniques from obscure Russian sources. 展开更多
关键词 artificial fertilisation assisted reproductive technologies(ART) CRYOPRESERVATION gonadotropic hormones OOCYTES SPERMATOZOA storage urinary spermatozoa
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Anti-Müllerian Hormone and Its Utility in Cattle Reproduction
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作者 Garza Arredondo Aimé Jazmín Moreno Degollado Gustavo +4 位作者 Adolfo-Soto Dominguez Pérez Hernández Raymundo Alejandro Rosales S. Cedillo Zamora-Ávila Diana Castillo-Velázquez Uziel 《Open Journal of Veterinary Medicine》 CAS 2023年第1期1-11,共11页
Reproductive biotechnologies offer us greater possibilities to improve animal genetics. However, the success of these depends on different factors such as the proper selection of the donor female. For this reason, end... Reproductive biotechnologies offer us greater possibilities to improve animal genetics. However, the success of these depends on different factors such as the proper selection of the donor female. For this reason, endocrine markers have been used to evaluate the ovarian reserve, which allow a successful selection of donors. Recent research has shown, among other things, that concentrations greater than 0.130 ng/mL of anti-Mullerian hormone (also known as Muller-inhibiting substance, which is a member of the transforming growth factor beta superfamily of growth and differentiation factors) are related to donors of more than fifteen transferable embryos. Therefore, this review describes studies showing that the measurement of anti-Müllerian hormone concentrations, before superovulation programs, reduces the costs per embryo produced. 展开更多
关键词 AMH Anti-Müllerian Hormone Reproductive Techniques Follicular Population Granulosa Cells SUPEROVULATION
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ON THE BASIC REPRODUCTION NUMBER OF GENERAL BRANCHING PROCESSES 被引量:1
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作者 蓝国烈 马志明 孙苏勇 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期1081-1094,共14页
Under a very general condition (TNC condition) we show that the spectral radius of the kernel of a general branching process is a threshold parameter and hence plays a role as the basic reproduction number in usual ... Under a very general condition (TNC condition) we show that the spectral radius of the kernel of a general branching process is a threshold parameter and hence plays a role as the basic reproduction number in usual CMJ processes. We discuss also some properties of the extinction probability and the generating operator of general branching processes. As an application in epidemics, in the final section we suggest a generalization of SIR model which can describe infectious diseases transmission in an inhomogeneous population. 展开更多
关键词 general branching process extinction probability reproduction kernel spectral radius TNC condition basic reproduction number SIR model
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Impact of the Three Gorges Dam on reproduction of four major Chinese carps species in the middle reaches of the Changjiang River 被引量:19
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作者 黎明政 段中华 +2 位作者 高欣 曹文宣 刘焕章 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第5期885-893,共9页
Silver carp(Hypophthalmichthys molitrix),bighead carp(Aristichthys nobilis),grass carp(Ctenopharyngodon idella),and black carp(Mylopharyngodon piceus) are the four major Chinese carps and are commercially important aq... Silver carp(Hypophthalmichthys molitrix),bighead carp(Aristichthys nobilis),grass carp(Ctenopharyngodon idella),and black carp(Mylopharyngodon piceus) are the four major Chinese carps and are commercially important aquaculture species in China.Reproduction of these carp has declined since the construction of the Three Gorges Dam(TGD) due to an altered water flow and thermal regime in the Changjiang(Yangtze) River.However,details of the changes in reproduction of the four species are not well understood.To assess the impact of the TGD on reproduction of the four carp,we investigated their eggs and larvae at Yidu City,which is 80 km below the TGD,during 2005-2012.We examined differences in larval abundance of the four species in the Jianli section(350 km downstream of the TGD) before(1997-2002)and after(2003-2012) construction of the TGD.Based on these observations,the first spawning date of the four species was delayed a mean of about 25 days after the dam was constructed.Mean egg abundance in the Yidu section of the river was 249 million and mean larval abundance was 464 million,which were significant decreases since the 1980 s.Moreover,larval abundance in the Jianli section after the dam was constructed was significantly lower than that before construction(ANCOVA,P<0.05).The observed larval abundance accounted for only 24.66%of the predicted value in 2003 when the dam was first inundated.The present spawning grounds between the TGD and Yidu section of the river are very similar to those described in the 1980 s,and some spawning grounds exist upstream of the TGD.Large free-flowing stretches upstream of the TGD and the creation of artificially flooded downstream reaches are needed to stimulate spawning and effectively conserve these four major Chinese carps species. 展开更多
关键词 Changjiang(Yangtze) River Three Gorges Dam Chinese carp reproduction eggs and larvae
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The role of dietary fibre in pig production,with a particular emphasis on reproduction 被引量:13
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作者 Selene Jarrett Cheryl J.Ashworth 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第4期783-793,共11页
Fibres from a variety of sources are a common constituent of pig feeds. They provide a means to utilise locallyproduced plant materials which are often a by-product of the food or drink industry. The value of a high f... Fibres from a variety of sources are a common constituent of pig feeds. They provide a means to utilise locallyproduced plant materials which are often a by-product of the food or drink industry. The value of a high fibre diet in terms of producing satiety has long been recognised. However the addition of fibre can reduce feed intake, which is clearly detrimental during stages of the production cycle when nutrient needs are high, for example in growing piglets and during lactation. More recently, fibre has been found to promote novel benefits to pig production systems,particularly given the reduction in antimicrobial use world-wide, concern for the welfare of animals fed a restricted diet and the need to ensure that such systems are more environmentally friendly. For example, inclusion of dietary fibre can alter the gut microbiota in ways that could reduce the need for antibiotics, while controlled addition of certain fibre types may reduce nitrogen losses into the environment and so reduce the environmental cost of pig production.Of particular potential value is the opportunity to use crude fibre concentrates as 'functional' feed additives to improve young pig growth and welfare. Perhaps the greatest opportunity for the use of high fibre diets is to improve the reproductive efficiency of pigs. Increased dietary fibre before mating improves oocyte maturation, prenatal survival and litter size; providing a consumer-acceptable means of increasing the amount of saleable meat produced per sow. The mechanisms responsible for these beneficial effects remain to be elucidated. However, changes in plasma and follicular fluid concentrations of key hormones and metabolites, as well as effects of the hypothalamic satiety centre on gonadotrophin secretion and epigenetic effects are strong candidates. 展开更多
关键词 FIBRE PIG PREGNANCY Production reproduction
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Adult nutrition affects reproduction and flight performance of the invasive fall armyworm,Spodoptera frugiperda in China 被引量:6
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作者 HE Li-mei JIANG Shan +5 位作者 CHEN Yu-chao Kris AGWYCKHUYS GE Shi-shuai HE Wei GAO Xi-wu WU Kong-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第3期715-726,共12页
Floral resources,such as carbohydrate-rich nectar or pollen,can bolster fitness and raise reproductive output of adult lepidopterans.Here,we used laboratory experiments to assess how those plant-derived foods impact a... Floral resources,such as carbohydrate-rich nectar or pollen,can bolster fitness and raise reproductive output of adult lepidopterans.Here,we used laboratory experiments to assess how those plant-derived foods impact adult fecundity,reproductive physiology and flight performance of an invasive strain of the fall armyworm,Spodoptera frugiperda(FAW;Lepidoptera:Noctuidae)in China.More specifically,supplementary feeding on bee pollen and honey enhanced FAW flight duration,testis size,ovarian development,longevity and adult fecundity.FAW adults attained the longest pre-oviposition(10.8 days)and oviposition period(6.8 days)and longevity(19.2 days)on 5%acacia honey.Upon access to 2.5%acacia honey and 2.5‰pine pollen,S.frugiperda attained the highest mating rate(79.7%),fecundity(644.9 eggs/female)and egg hatching rate(82.3%).Feeding on honey further delayed decay of male testes,while ovarian development was enhanced when female moths were allowed access to 2.5%honey and 2.5‰pine pollen.Upon feeding on 5%honey solution,S.frugiperda engaged in flight over the longest duration(9.5 h),distance(29.9 km)and speed(3.1 km h-1).Honey had a comparatively greater effect on the above parameters than pollen.Our findings help decipher FAW invasion patterns and population dynamics,facilitate the development of nutritional attractants,and contribute to integrated pest management of this newly-invasive pest in eastern Asia. 展开更多
关键词 supplementary nutrition FECUNDITY adult reproduction flight parameter invasion biology nutritional physiology
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How cushion communities are maintained in alpine ecosystems: A review and case study on alpine cushion plant reproduction 被引量:5
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作者 Jianguo Chen Yanbo Li +1 位作者 Yang Yang Hang Sun 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第4期221-228,共8页
Cushion species occur in nearly all alpine environments worldwide. In past decades, the adaptive and ecosystem-engineering roles of such highly specialized life forms have been well studied. However, the adaptive stra... Cushion species occur in nearly all alpine environments worldwide. In past decades, the adaptive and ecosystem-engineering roles of such highly specialized life forms have been well studied. However, the adaptive strategies responsible for cushion species reproductive success and maintenance in severe alpine habitats remain largely unclear. In this study, we reviewed the current understanding of reproductive strategies and population persistence in alpine cushion species. We then present a preliminary case study on the sexual reproduction of Arenaria polytrichoides(Caryophyllaceae), a typical cushion species inhabiting high elevations of the Himalaya Hengduan Mountains, which is a hotspot for diversification of cushion species. Finally, we highlight the limitations of our current understanding of alpine cushion species reproduction and propose future directions for study. 展开更多
关键词 Alpine ecosystem Cushion plant Community recruitment Growth rate Life-span reproduction
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The type, position and age effect on the cutting reproduction of Picea crassifolia and its rooting mechanism in the Qilian Mountains 被引量:5
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作者 Jianjun Kang Wenzhi Zhao +3 位作者 Ming Zhao Guangyu Li Jiqiang Zhang Zhisheng Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期993-1002,共10页
Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its r... Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its rooting mechanism, cuttings of P. crassifolia with different cutting types (softwood, hardwood and root), positions (top, upper, middle and bottom) and ages (7, 10, 15, 20, 25 year-old) were cultivated in a field experiment. One- year old softwood and hardwood cuttings were collected from 7-, 10-, 15-, 20-, and 25 year-old healthy ortets to analyze the changes from endogenous hormones and organic nutrients. Results indicate that the softwood cut- tings (0.5-1.0 cm in diameter) from upper branches of 15 year-old ortets shows better growth performance by improving rooting indexes, including a significant increasein rooting rate and a decrease in basal rot rate. Concomi- tantly, increasing rooting quantity and root length also increased. It is noteworthy that the high rooting rate of P. crassifolia cuttings due to its ability to accumulate high concentrations of indole-3-acetic acid (IAA) and total carbon (TC) rather than abscisic acid (ABA) and total nitrogen (TN). The rooting rate was mainly regulated by the IAA/ABA and TC/TN ratio. In summary, our results suggest that the softwood cuttings (0.5-1.0 cm in diameter) from upper branches of 15 year-old P. crassifolia can be considered as an effective strategy to improve cutting rooting rate, and the IAA/ABA and TC/TN ratio was one of the main factors limiting the cutting rooting rate of P. crassifolia. 展开更多
关键词 Picea crassifolia Kom TYPE Positionand age effect Cutting reproduction Rooting rate HORMONES Organic substances
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Growth and Reproduction of Artificially Fed Cnaphalocrocis medinalis 被引量:5
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作者 Xu Jian LI Chuan-ming +5 位作者 YANG Ya-jun QI Jian-hang ZHENG Xu-song Hu Rong-li Lu Zhong-xian LIU Qin 《Rice science》 SCIE 2012年第3期247-251,共5页
The growth and reproduction of rice leaffolder,Cnaphalocrocis medinalis,fed on an artificial diet were studied.The results showed that the larvae were able to grow and pupate on the artificial diet.The durations of la... The growth and reproduction of rice leaffolder,Cnaphalocrocis medinalis,fed on an artificial diet were studied.The results showed that the larvae were able to grow and pupate on the artificial diet.The durations of larvae and pupas of C.medinalis on the artificial diet were 28.1 d and 10.1 d,postponed 4.9 d and 1.7 d respectively,compared with those reared with rice leaves.The number of ovipositions was 41.6 per female,26.2% higher than that fed on rice leaves.Survival rate curve of larvae was a descent function of mortality-age,with no significant differences from the curve of larvae fed on rice leaves.The net reproductive rate (Ro),intrinsic rate of increase (rm) and finite rate of increase (λ) of the population fed on diet were 17.6928,0.0884 and 1.0924,respectively,and the mean generation time (T) and double time (td) were prolonged 4.9 d and 1.3 d in comparison with the treatment of rice leaves.Population trend index (I) was 3.26,indicating a growing number of the population of C.medinalis fed on artificial diet. 展开更多
关键词 Cnaphalocrocis medinalis artificial diet experimental population GROWTH reproduction
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The effects of DDT on the feeding, respiration, survival, and reproduction of Sinocalanus tenellus(Copepoda:Calanoida) 被引量:3
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作者 XU Donghui LIU Guangxing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第9期133-138,共6页
DDT (dichloro-diphenyl-trichloroethane) as a type of organochlorine pesticides, is an important compo nent of pesticides pollution whose impact on the marine ecosystem is urgently to be evaluated. To investi gate th... DDT (dichloro-diphenyl-trichloroethane) as a type of organochlorine pesticides, is an important compo nent of pesticides pollution whose impact on the marine ecosystem is urgently to be evaluated. To investi gate the biological effects of DDT on the marine ecosystem, copepods being the main contributor of sec ondary productivity in the marine ecosystem, were selected as target animals. The influence of DDT on the feeding, respiration, survival, and reproduction of Sinocalanus tenellus (S. tenellus) was analyzed and the antioxidant enzymes activities in the individuals were measured under different exposure concentrations of DDT. The 48 h median lethal concentration (LC50) and 96 h LC50 of DDT to S. tenellus were 5.44 and 2.50 pg/dma, respectively. The filtration rates, grazing rates, and respiration of S. tenellus decreased apparently with increased DDT concentrations. Under lower concentration (〈625 ng/dm3) of DDT, the activities of the antioxidant enzymes, including superoxide dismutase and catalase in the animals increased significantly compared with those in the animals without any exposure to DDT, which suggested that the antioxidant enzymes can protect the animals from oxidative damage. However, the activity of the antioxidant enzyme decreased when the animals were exposed to higher concentration (1250-2 500 ng/dma) of DDT. The sur-vival rate of both females and males was reduced when they were exposed to DDT less than 250 ng/dm3, but females showed higher survival rate than males when they are under the same concentration. The hatching ratio and the egg diameters of S. tenellus decreased significantly when they were exposed to DDT with a concentration of 25 and 250 ng/dm3, however, the cumulative egg production did not show any significant variation when the animals were exposed to the above DDT concentration. These data in the preset study suggested that exposure to DDT can cause the variation of the species composition of copepods, and further affect the marine ecosystem. 展开更多
关键词 DDT Sinocalanus tenellus SURVIVAL reproduction FEEDING RESPIRATION antioxidant enzyme
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Effects of constant and stage-specific-alternating temperature on the survival, development and reproduction of the oriental armyworm, Mythimna separata(Walker)(Lepidoptera: Noctuidae) 被引量:3
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作者 LI Bo-liao XU Xiang-li +1 位作者 JI Jia-yue WU Jun-xiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第7期1545-1555,共11页
Migratory insects make diverse adaptive strategies in response to changes in external environment. Temperature has an impact on the survival, development, reproduction, and migration initiation of insects. Previous re... Migratory insects make diverse adaptive strategies in response to changes in external environment. Temperature has an impact on the survival, development, reproduction, and migration initiation of insects. Previous research has primarily been focused on the effects of constant temperature on populations, but changing temperature has received less attention. Three constant temperature treatments(20, 25 and 30℃) and three pupal-alternating temperature treatments(20–25, 25–20 and 25–30℃) were set up to study the relationship between temperature and population development by age-stage, two-sex life table analysis in the oriental armyworm, Mythimna separata Walker, a notorious migratory pest in grain crops. The 25℃ treatment was considered optimal with 20 and 30℃ as low suitable temperature and high temperatures, respectively. The survival rate was relatively low before third instar larvae at 20℃(63.0%) and 20–25℃(70.1%), and extreme low after pupal stage at 30℃(20.6%). Developmental duration of each stage was negatively correlated with temperature. The adult preoviposition period, when most migratory insects initiate migration, was the shortest at 25℃(2.69d) but was lengthened at both low suitable(7.48d for 20℃, 6.91d for 25–20℃ and 4.57d for 20–25℃) and high temperatures(3.74d for 25–30℃ and 5.00d for 30℃). Both low suitable and high temperature decreased lifetime fecundity, net reproductive rate and the intrinsic rate of increase, with variability observed across developmental duration and stage during non-optimal temperature. The results expand knowledge of the relationship between changing temperature and armyworm population development, and adaptive strategies in complex ambient environment. 展开更多
关键词 Mythimna separata stage-specific-alternating temperature life table SURVIVAL reproduction
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Effect of methanol extract of Ricinus communis seed on reproduction of male rats 被引量:2
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作者 Yinusa Raji Ahmed Kolade Oloyo Ayodele Olufemi Morakinyo 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第1期115-121,共7页
Aim: To investigate the effect of methanol extract of Ricinus communis seed (RCE) on male rats reproductive functions. Methods: Thirty-two male albino rats were divided into four groups. Groups 1, 2 and 3 were gav... Aim: To investigate the effect of methanol extract of Ricinus communis seed (RCE) on male rats reproductive functions. Methods: Thirty-two male albino rats were divided into four groups. Groups 1, 2 and 3 were gavaged with 0.2 mL of 2.5% tween 80 (RCE vehicle; control) or 20 mg/(kg-d) and 40 mg/(kg-d) of RCE, respectively, for 30 days, and group 4 was also gavaged with 40 mg/(kg.d) of RCE, but was allowed a recovery periold of 30 days. Five untreated female rats were cohabited with male rats in each group from day 25 of RCE treatment for 5 days, except group 4, where cohabitation began on day 25 of the recovery period. All male rats were sacrificed 24 h after the experiments. The female rats were laparatomized on day 19 of pregnancy and the number and weight of litters were recorded. Results: There was a significant decrease (P 〈 0.01) in the weight of the reproductive organs, sperm functions and serum levels of testosterone in RCE treated rats. There was disorganization in the cytoarchitecture of the testes, disruption of the seminiferous tubules and erosion of the germinal epithelium. The number and weight of litters of rats in groups 2 and 4 decreased significantly (P 〈 0.05) but no changes were observed in group 3. RCE caused no changes in liver, kidney, heart or body weights in male rats. Conclusion: RCE has a reversible negative impact on male reproductive functions, which appears to be mediated via gonadal disruption in testosterone secretion. (Asian J Androl 2006 Jan; 8: 115-121) 展开更多
关键词 Ricinus communis SPERM FERTILITY TESTOSTERONE reproduction
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Morphological and functional alterations of female reproduction after regular exposure of bamboo shoots of North East India 被引量:2
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作者 Deotima Sarkar Arijit Chakraborty +1 位作者 Dakshayani Mahapatra Amar K Chandra 《Asian pacific Journal of Reproduction》 2017年第4期151-157,共7页
Objective:To evaluate the effect of daily consumption of bamboo shoots (BS) on the morphological features and functional status of the female reproductive system in adult with respect to thyroid.Methods: Adult female ... Objective:To evaluate the effect of daily consumption of bamboo shoots (BS) on the morphological features and functional status of the female reproductive system in adult with respect to thyroid.Methods: Adult female rats were divided into control and experimental groups of six each. Control group was given normal diet while experimental group was fed BS by 1/3rd replacement of 180 g of their foodi.e.60 g of BS containing 35 g of goitrogens of cyanogenic origin such that each rat likely consumed 6 mg/100 g of body weight per day for a period of 45 d. Morphological features like changes in body weight and organ weight were noted. Key steroidogenic enzyme levels viz?53β hydroxysteroid dehydrogenase (HSD) and 17β HSD along with serum estradiol, estriol and progesterone levels were measured. Estrous cyclicity of the animals monitored regularly followed by histological analysis of thyroid, ovary and uterus at the end of experimentation.Results:Increase in body weight, thyroid gland weight and thyroid stimulating hormone, decrease in serum triiodothyronine and thyroxine, a decrease in ovarian as well as uterine weight and the activity of steroidogenic enzymes?53β HSD andβ17β HSD along with diminished serum estradiol, estriol and progesterone levels were noted;while histological plates showed prominent degenerative changes in both the ovary and uterus. Estrous cyclicity of the treated animals were irregular and almost stopped at diestrous stage of the cycle in the latter stage of the treatment as compared to control.Conclusions: Overall results indicates that BS rich in cyanogenic constituents induces biochemical hypothyroidism in the experimental animals that acts in corroboration to cause morphological and functional alteration of reproductive organs indicating its likely impact in fertility on continued use. 展开更多
关键词 BAMBOO SHOOTS Dietary goitrogens Female reproduction ESTROGEN Steroidogenic ENZYMES REPRODUCTIVE disruptor
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Outcome of Assisted Reproduction Treatment in Women with Extremely Low Antimullerian Hormone (AMH) Levels 被引量:5
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作者 Munawar Hussain David J. Cahill +1 位作者 Valentine Akande Uma Gordon 《Open Journal of Obstetrics and Gynecology》 2014年第15期961-966,共6页
Purpose: To evaluate age related ovarian response to controlled ovarian hyperstimulation, clinical pregnancy and ongoing pregnancy rates beyond 20 weeks in women undergoing assisted reproduction treatment (ART) with a... Purpose: To evaluate age related ovarian response to controlled ovarian hyperstimulation, clinical pregnancy and ongoing pregnancy rates beyond 20 weeks in women undergoing assisted reproduction treatment (ART) with antimullerian hormone (AMH) levels of <5 pmol/l. Methods: Retrospective analysis of data from 63 women with AMH of In-vitro?fertilization, IVF and intracytoplasmic sperm injection, ICSI) cycle. Results were analyzed after dividing patients in two groups, group 1 included women of ≤38 years and group 2 > 38 years of age. Non parametric variables were expressed as median (Interquartile range) and compared by Kruskal-Wallis test. Categorical variables were expressed as numbers with proportions (%) and compared by Fisher’s exact test. Results: There was no statistical difference in body max index, level of antimullerian hormone (AMH), follicle stimulating hormone (FSH), dose of gonadotrophins used and cycles cancellation rate in two groups. Although number of oocytes retrieved (median 5), clinical pregnancy (18.4%) and ongoing pregnancy rate beyond 20 weeks (18.4%) was higher in group 1, there was no statistical difference between the two groups. There was one miscarriage in group 2. Conclusion: Women with extremely low-serum AMH levels can still have clinical pregnancy and ongoing pregnancies beyond 20 weeks after ART, though chances will be lower than women with normal ovarian reserve. 展开更多
关键词 EXTREMELY LOW Antimullerian HORMONE Assisted reproduction Treatment Clinical PREGNANCY Ongoing PREGNANCY MISCARRIAGE Rate
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