Bulletin of the Torrey Botanical Club最新文献

{"title":"Germination of macrophytes from a Delaware River tidal freshwater wetland","authors":"M. A. Leck","doi":"10.2307/2996306","DOIUrl":"https://doi.org/10.2307/2996306","url":null,"abstract":"LECK, M. A. (Biology Department, Rider University, Lawrenceville, NJ 08648). Germination of macrophytes from a Delaware River tidal freshwater wetland. Bull. Torrey Bot. Club 123: 48-67. 1996. The effects of burial and soil moisture (seeds were on the surface, or buried at 1 and 5 cm with drained, saturated, or flooded water levels), inundation (Petri dishes, and open and closed jars), and storage (-0 and -100% RH), as well as of light and various temperature regimes, were examined. Focus was on ten species (Amaranthus cannabinus (L.) Sauer, Ambrosia trifida L., Bidens laevis (L.) BSP, Impatiens capensis Meerb., Peltandra virginica (L.) Schott. & Endl., Phalaris arundinacea L., Pilea pumila (L.) A. Gray, Polvgonum arifblium L., Polygonum punctatum Elliott, and Sagittaria latifolia Willd.); five others were also considered to a limited extent (Alisma subcordatum Raf., Carex lurida Wahlenb., Cicuta maculata L., Cuscuta gronovii Willd., and Pontederia cordata L.). Species varied in their germination responses. Those with the same seed bank strategy (transient or persistent) had different dormancy mechanisms although seeds with persistent seed banks required temperatures >50C and germination for most was enhanced by light. Responises to burial and moisture level showed that larger seeded species were able to germinate from greater depth, but germination was greater in drained samples. There were three types of responses to inundation: (1) requirement for at least modest amounts of oxygen, (2) requirement for hypoxic conditions, and (3) those having good germination regardless of inundation regime. Seed bank losses and relatively short seed bank longevity could be accounted for by germination following afterripening, adverse effects of prolonged inundation, failed gerrnination (e.g., germination at depths that preclude the seedling from reaching the surface), and predation. Differences between the seed characteristics of species of this and those of other wetlands relate to the transient nature of the seed bank and to wetland hydrology. Variable responses to drying have implications for wetland restoration projects.","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":"123 1","pages":"48-67"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996306","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68405576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cleistogamy and seed heteromorphism in Triplasis purpurea (Poaceae)","authors":"G. P. Cheplick","doi":"10.2307/2996303","DOIUrl":"https://doi.org/10.2307/2996303","url":null,"abstract":"CHEPLICK, G. P (Department of Biology, The College of Staten Island of the City University of New York, Staten Island, NY 10314). Cleistogamy and seed heteromorphism in Triplasis purpurea (Poaceae). Bull. Torrey Bot. Club 123: 25-33. 1996.-Two populations of the annual grass Triplasis purpurea on Staten Island, New York, were examined to determine the importance of cleistogamy (CL) to caryopsis (seed) production, and whether CL was associated with a position-dependent seed heteromorphism, as noted in other CL grasses. The percentage of tillers with terminal panicles bearing chasmogamous spikelets was low in both populations (s35%), and at least 72% of the seeds produced by tillers with terminal panicles were matured on axillary panicles in CL spikelets enclosed by leaf sheaths. A marked seed heteromorphism exists in T. purpurea: from the lower to the upper nodes along a tiller, there was an increase in seed number with a concurrent decrease in mean seed mass. This heteromorphism was further investigated in a greenhouse experiment where plants were subjected to low, medium, and high levels of soil nutrients by periodic addition of N-P-K fertilizer. Again, there was a progressive increase in seed number with a concordant decrease in mean seed mass from the lower to the upper tiller nodes. Differences in seed number among nutrient treatment groups were greatest in the upper nodes, but differed very little in the lower nodes. This is the first report of seed heteromorphism in this species. It is suggested that the position-dependent variation in seed mass reflects differences in the timing and length of the maturation period. From an evolutionary perspective, this pattern of seed heteromorphism may represent an adaptation to an unpredictable, highly-disturbed environment.","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":"123 1","pages":"25"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996303","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68405470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of gap size and regeneration niche on species coexistence in bryophyte communities","authors":"R. W. Kimmerer, C. Young","doi":"10.2307/2996302","DOIUrl":"https://doi.org/10.2307/2996302","url":null,"abstract":"Relative abundance of the two species varies with availability of the appropriate regeneration niche, which is a function of the local disturbance regime. Rodent activity may both produce the gaps favored by D. flagellare and facilitate its dispersal to them. Dominance of T. pellucida is associated with larger gaps produced by decay. The interaction of the regeneration niche and the disturbance regime are found to be primary determinants of community structure on this unstable substrate.","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":"123 1","pages":"16"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996302","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68405459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"More on the Southward Spread of Common Milkweed, Asclepias syriaca L.","authors":"R. Wyatt","doi":"10.2307/2996307","DOIUrl":"https://doi.org/10.2307/2996307","url":null,"abstract":"","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":"123 1","pages":"68"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996307","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68405119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"More flowers or new cladodes? Environmental correlates and biological consequences of sexual reproduction in a Sonoran Desert prickly pear cactus, Opuntia engelmannii","authors":"J. E. Bowers","doi":"10.2307/2996304","DOIUrl":"https://doi.org/10.2307/2996304","url":null,"abstract":"BOWERS, JANICE E. (U.S. Geological Survey, 1675 W. Anklam Road, Tucson, AZ 85745). More flowers or new cladodes? Environmental correlates and biological consequences of sexual reproduction in a Sonoran Desert prickly pear cactus, Opuntia engelmannii. Bull. Torrey Bot. Club 123: 34-40. 1996.-Should a platyopuntia expend all aerolar meristems in flower production, no new cladodes could be produced, and further reproductive effort and vegetative growth would cease. To investigate the trade-off between flower and cladode production, the numbers of flowers, fruits, and cladodes were monitored for 4 years on 30 Opuntia engelmannii Saim-Dyck. plants on Tumamoc Hill, Tucson, Arizona. Plant size controlled the number of flowers initiated each spring. The proportion of flowers that developed (i.e., did not abort) was perhaps determined by December-February rainfall in the months before bloom, with more being developed in the wettest years. Models based on different ratios of initiated cladodes to initiated flowers demonstrated that continued high investment in flowers and fruits would eventually terminate reproduction altogether; therefore periods of high sexual reproduction should alternate with periods of high vegetative growth. In the first 3 years of this study, the ratio of new cladodes to initiated flowers was low, showing a high investment in sexual reproduction. As suggested by the model, the population recouped this investment in the fourth year, when the number of new cladodes was nearly 3 times the 1992-1994 mean, and the number of initiated flowers was only 73% of the 3-year mean.","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":"123 1","pages":"34-40"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996304","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68405534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The European Garden Flora: A Manual for the Identification of Plants Cultivated in Europe Both Out-of-Doors and Under Glass. 1995. Volume 4: Dicotyledons (Part II): Dilleniaceae to Krameriaceae.","authors":"R. Barneby, J. Cullen","doi":"10.2307/2996310","DOIUrl":"https://doi.org/10.2307/2996310","url":null,"abstract":"","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":"123 1","pages":"71"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996310","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68405190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nature's Champion: B. W. Wells, Tar Heel Ecologist.","authors":"J. Snyder, J. R. Troyer","doi":"10.2307/2996311","DOIUrl":"https://doi.org/10.2307/2996311","url":null,"abstract":"","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":"123 1","pages":"72"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996311","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68405201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An allozyme study of two sibling species of Lemna (Lemnaceae) with comments on their morphology, ecology and distribution","authors":"D. Crawford, E. Landolt, D. Les","doi":"10.2307/2996300","DOIUrl":"https://doi.org/10.2307/2996300","url":null,"abstract":"CRAWFORD, D. J. (Department of Plant Biology, The Ohio State University, Columbus, OH 43210), E. LANDOLT (Geobotanisches Institut ETH, Zurichbergstrasse 38, CH-8044, Zurich, Switzerland) AND D. H. LES (Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269). An allozyme study of two sibling species of Lemna (Lemnaceae) with comments on their morphology, ecology and distribution. Bull. Torrey Bot. Club 123: 1-6. 1996.-Enzyme electrophoresis was employed to examine divergence between Lemna mninuta H.B.&K. and L. valdiviana Phil., two nearly indistinguishable species comprising sect. Uninerves of Lemna. Fifteen presumptive loci were resolved for 25 clones of Lemna minuta and 26 of L. valdiviana. Genetic identity between the two species is 0.70, which is near the mean value for congeneric species of flowering plants, but is much higher than values reported for other species of Lemnaceae. With the exception of two clones, the taxonomic designations of the strains correlated with monomorphism for alternative alleles at two MDH loci. The two species are highly differentiated at two other loci as well. Although the taxa are morphologically similar, they differ in geographic distribution, flavonoid chemistry, and certain physiological and ecological attributes. The relatively high identity at allozyme loci compared to other Lemnaceae suggests that L. minuta and L. valdiviana are closely related and recently diverged sister species.","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":"23 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996300","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68405381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Life History Strategies of Florida Scrub Plants in Relation to Fire","authors":"E. Menges, Nancy Kohfeldt","doi":"10.2307/2996320","DOIUrl":"https://doi.org/10.2307/2996320","url":null,"abstract":"","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":"122 1","pages":"282-297"},"PeriodicalIF":0.0,"publicationDate":"1995-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996320","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68405323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Quiescent Center in Aerial Roots of Orchids","authors":"V. Raghavan, C. Goh","doi":"10.2307/2996318","DOIUrl":"https://doi.org/10.2307/2996318","url":null,"abstract":"","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":"47 1","pages":"269"},"PeriodicalIF":0.0,"publicationDate":"1995-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996318","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68405247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}