水稻恶苗病菌在浸种过程中的扩散   总被引：2，自引：2，他引：0  

潘以楼  杨敬辉  朱桂梅 《安徽农业科学》2000,28(5):616-617

研究表明 ,稻恶苗病带菌种子在浸种液中 ,恶苗病菌小型分生孢子的数量与种子带菌率的高低、浸种时间的长短成正相关 ;由于稻种中寄藏的恶苗病菌在水中产生大量分生孢子 ,使得水稻种子带菌率明显提高 ,苗期恶苗病发病率也显著增加  相似文献   

辽东栎的繁殖体及其与种群更新的关系   总被引：3，自引：0，他引：3  

闫兴富 《西北林学院学报》2008,23(5)

就辽东栎的种子雨及其传播动力、种子传播后的命运、种子萌发、幼苗建立、实生更新对动物捕食的适应和萌生特性等方面进行了简要综述,并对未来研究的发展方向进行了展望。辽东栎种子是多种脊椎动物和鸟类的食物资源,种子萌发和幼苗形成期间的捕食压力导致其实生更新困难,但捕食动物对种子的搬运和埋藏对辽东栎种群更新和扩散具有重要意义;光照和水分对辽东栎的种子萌发和幼苗建立都具有重要影响,在森林管理工作中,适当干扰 (例如择伐) 对辽东栎的种子萌发、幼苗生长与存活以及种群更新都是有利的。较强的萌生能力对维持辽东栎的遗传多样性和种群活力具有重要的生态学意义;在强干扰条件下,萌生作为辽东栎通过从种子、幼苗、幼树到成年植株过程中的更新瓶颈的途径,是辽东栎实现种群更新的主要对策。  相似文献   

Ontogenetic movements of juvenile blacktip reef sharks: evidence of dispersal and connectivity between coastal habitats and coral reefs     

A Chin  MR Heupel  CA Simpfendorfer  AJ Tobin 《水产资源保护:海洋与淡水生态系统》2013,23(3):468-474

Swimming responses of larval and juvenile freshwater fishes to nearshore and offshore water sources          下载免费PDF全文

Timothy D. Malinich  Kevin Pangle 《Ecology of Freshwater Fish》2018,27(4):933-939

Dispersal of young fish through wind‐driven currents has a growing research focus in large freshwater lakes; however, the influence of behaviour on such dispersal has not been tested. Fish may orient to different environmental cues and use swimming behaviours to navigate towards or retain their position within important habitats. To examine the ability of larval and juvenile fishes of the Laurentian Great Lakes to perceive and orient to nearshore or offshore habitats, we carried out a series of behavioural trials in a flume in which fish choose between different combinations of nearshore and offshore water, and well water. Water and a natural assemblage of larval and juvenile nearshore fish (Dominant species: white sucker, Catostomus commersonii, and spottail shiners, Notropis hudonius) used in the experiment were collected from northern Lake Michigan near Beaver Island. Results of our study suggest that young fish are capable of distinguishing and responding to different water sources, indicating a potential to orient within their environment, such as through the use of olfactory cues. We did not see a difference in fish response to changing concentrations of water cues, possibly suggesting that the threshold for fish response occurs at lower concentrations than were tested in our experiments. This preliminary study into orientation of Great Lakes fishes demonstrates the capacity of these fish to orient to cues in water sources and indicates the need to consider active movement in future studies of larval dispersal and habitat choice in the large freshwater lakes.  相似文献   

Roads limit of seed dispersal and seedling recruitment of Quercus chenii in an urban hillside forest     

《Urban Forestry & Urban Greening》2018

Paved roads in urban forests cause forest fragmentation and thus reduce animal populations, threaten dispersal and recruitment of animal-dispersed plants. Here, we tracked animal-mediated seed dispersal of Quercus chenii in the urban forest centre and near roadsides to test the effect of paved roads on seed dispersal and recruitment. We conducted experiments in a forest patch in urban areas of Wuhan, China. The forest was dominated by the focal tree species and separated by paved roads. Only two potential seed dispersal animals, one rodent (Niviventer confucianus) and one jay (Garrulus glandarius) were observed in this stand. Seeds were removed farther but not as fast in the forest centre compared to roadsides, while no differences of seed fate, dispersal direction, and seedling establishment were detected between the forest centre and roadsides, indicating the thick vegetation along roadsides provided feeding shelters for small animals. However, when compared with primary forests containing more seed dispersers, seed removal rate in this urban forest fragment was much slower in both forest centre and roadside. Furthermore, due to road barriers, seeds were seldom moved across the paved road and remained in the fragmented stand, reflecting a limited function of seed dispersers. These results suggested paved roads isolated forests into small “islands” and weakened the ecological function of seed dispersers by impeding long distance seed dispersal. Reintroducing dispersers and building wildlife corridors would be impactful ways to restore urban forest patches.  相似文献   

Galápagos land iguana (Conolophus subcristatus) as a seed disperser          下载免费PDF全文

Anna TRAVESET  Manuel NOGALES  Pablo VARGAS  Beatriz RUMEU  Jens M. OLESEN  Patricia JARAMILLO  Ruben HELENO 《Integrative zoology》2016,11(3):207-213

The role of the most common land iguana (Conolophus subcristatus) in the Galápagos Islands as an effective seed disperser is explored in this study. A total of 5705 seeds of 32 plant species were identified from 160 scats, 4545 of which (80%) appeared visually undamaged. Germination trials of 849 seeds from 29 species revealed that at least 10 species remained viable after passing through the iguana's gut, although only a small proportion of those seeds (4%) germinated. In any case, we argue that C. subcristatus exerts an important role on the 7 Galapagos islands where it occurs because of its abundance and capacity to ingest and disperse seeds at long distances. Our results strongly suggest that the Galápagos C. subcristatus plays an important role as a seed disperser of not only of native species but also some introduced plants in the Galápagos Islands.  相似文献   

Telemetry research on elusive wildlife: A synthesis of studies on giant pandas          下载免费PDF全文

Thomas CONNOR  Vanessa HULL  Jianguo LIU 《Integrative zoology》2016,11(4):295-307

Telemetry studies that track animals through space and time can lead to advances in scientific understanding that are vital in conservation efforts. For example, telemetry studies of the giant panda (Ailuropoda melanoleuca) have shed light on many aspects of panda biology, but small sample sizes in each separate study make it difficult to draw broad conclusions. To overcome this problem we conducted the first synthesis of all 5 panda telemetry studies conducted to date. Using these data we investigated patterns in 6 main topics: home range, space–use interactions, core areas, movement patterns, seasonal migration and natal dispersal. We found that panda home range sizes do not vary between 2 main mountain ranges (Qionglai and Qinling), as was previously believed. Our results also suggest that female pandas increase their movement in the mating season: a behavior typically attributed only to males. We found and summarized telemetry and genetic evidence for female natal dispersal in the giant panda. Our synthesis highlights the need for additional research relating panda behavior to human disturbance factors, and can aid future studies on giant pandas as well as other species.  相似文献   

Differentiation in seed hoarding among three sympatric rodent species in a warm temperate forest   总被引：1，自引：0，他引：1  

Jiqi LU  Zhibin ZHANG 《Integrative zoology》2008,3(2):134-142

Although seed hoarding by rodents has been extensively studied, differentiation in seed‐hoarding behaviors among sympatric rodent species has not been well investigated. Using semi‐natural enclosures, we demonstrated that three sympatric rodent species showed clear differentiation in food selection, scatter versus larder hoarding behaviors and eating behaviors when offered seeds of four plant species from a warm temperate forest in northern China. The large field mouse Apodemus peninsulae preferred seeds of wild apricot (Prunus armeniaca) and Liaodong oak (Quercus liaotungensis), whereas the Chinese white‐bellied rat Niviventor confucianus preferred seeds of cultivated walnut and Liaodong oak, and the David's rock squirrel Sciurotamias davidianus preferred seeds of cultivated walnut, wild apricot and Liaodong oak. All three rodents showed larder hoarding of seeds from all four plant species, but the large field mouse showed scatter hoarding of wild apricot, and the David's rock squirrel showed scatter hoarding of Liaodong oak and wild walnut. Acorns of Liaodong oak, which have a soft seed hull, were more often eaten in situ, whereas wild walnuts, which have a hard seed hull and more tannin, were less hoarded by all rodent species. Differentiation in the scatter versus larder hoarding behaviors of sympatric rodent species suggests that sympatric rodents play different roles in the regeneration of different sympatric plant species.  相似文献   

Importance of bird traits for seed dispersal patterns of co‐fruiting trees in a patchy forest     

Ning LI  Zheng WANG  Shuai ZHANG  Chuan YAN  Xinhai LI  Changhu LU 《Integrative zoology》2019,14(5):470-478

Habitat fragmentation is globally one of the most important drivers of change in biodiversity. Seed dispersal by birds is crucial for tree regeneration in remnant patchy forests, yet how bird traits affect seed dispersal pattern is still poorly understood. We studied the extent to which bird traits affect seed‐removal networks and whether these traits affect seed deposition and seedling recruitment for 3 co‐fruiting tree species (Taxus chinensis, Cinnamomum bodinieri and Machilus thunbergii) in a patchy forest. A total of 17, 18 and 10 bird species were recorded foraging for seeds of T. chinensis, M. thunbergii and C. bodinieri, respectively. Frequency of bird visitation increased with tail length, wing length and body length. Furthermore, bird body length, bill length, body weight and wing length were important in the strength of the seed removal network. During foraging, 6 bird species exhibited different patterns of microhabitat utilization and their perching frequency increased with bird weight and tarsus length. As a consequence, frequency of habitat use, bird length and tarsus length were important in determining the number of deposited seeds. For seedling recruitment, seedling number increased with bird tarsus length and weight, but decreased with wing length. Overall, our results showed that various bird traits not only affected seed removal, but also influenced the subsequent processes of seed deposition and seedling distribution in a patchy forest. These results thus highlight the importance of large‐bodied birds for plant recruitment and point out the need to prioritize the protection and conservation of these birds in remnant patchy forests.  相似文献   

The horizontal transfer of Salmonella between the lesser mealworm (Alphitobius diaperinus) and poultry manure          下载免费PDF全文

T. L. Crippen  C. L. Sheffield  R. C. Beier  D. J. Nisbet 《Zoonoses and public health》2018,65(1):e23-e33

There is need to determine the nature of enduring reservoirs of Salmonella contributing to perpetual contamination within poultry flocks. The dispersal of Salmonella between birds, litter and the lesser mealworm has been established, but the extent that these act as critical components in the epidemiology of Salmonella infection during broiler grow‐out and flock rotation has not been delineated; in particular, the level of participation by the lesser mealworm beetles (LMB) as agents of retention and dispersal. This study defines this route of transmission and provides empirical data on bacterial loads that facilitate Salmonella transfer. Results showed differential Salmonella transfer dependent on bacterial concentration. At 10³ cfu/ml, only a small, but not significant, amount of Salmonella was transferred, from the LMB to the manure and back to uninfected LMB; while from 10⁵ to 10⁷ cfu/ml, a significant acquisition and transfer occurred both internally and externally to the LMB over 4 and 24 hr exposures. These data will be used in correlation with facility management practices to develop intervention strategies to mitigate the establishment and spreading of reservoir Salmonella populations contributing to pre‐harvest contamination of poultry flocks.  相似文献