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P. Vulgaris (p + vulgari)
Selected AbstractsThe Spatial Segregation of Zooplankton Communities with Reference to Land Use and Macrophytes in Shallow Lake Wielkowiejskie (Poland)INTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 3 2009Natalia Kuczy, ska-Kippen Abstract The spatial distribution of zooplankton in relation to two types of land-use (forested and pastoral-arable) of a lake's surroundings and to various habitats (helophytes, elodeids, nymphaeids and open water) was examined along 16 parallel transects on a macrophyte-dominated lake (area , 13.3 ha; mean depth , 1.4 m). The type of habitat was the main determinant of zooplankton community structure. Dissected-leaved elodeids harboured the richest and most abundant community with typically littoral (e.g., Colurella uncinata) and pelagic species (e.g., Keratella cochlearis). Two species (Polyarthra major and P. vulgaris) selectively chose the open water and one (Lecane quadridentata) the Typha stand. No spatial differentiation in zooplankton abundance was recorded between the two types of the catchment area. One possible explanation may be the shallowness and small area of this lake which may support full mixing and no difference in physical-chemical gradients. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Manipulation of in vivo pollination techniques to improve the fertilization efficiency of interspecies crosses in the genus PhaseolusPLANT BREEDING, Issue 2 2007V. Gurusamy Abstract Phaseolus angustissimus A. Gray contains genes for traits of interest for dry bean (P. vulgaris) breeders. F1 hybrids can be produced but introgression through backcrossing has been a problem. One of the main impediments is the time required between pollination and fertilization when F1 hybrids of P. vulgaris/P. angustissimus are backcrossed with P. vulgaris. In an attempt to reduce this time, the effect of alternative pollination techniques was studied. The rate and the time of fertilization were ascertained using three different pollen types (pollen germinated in vitro, fresh pollen (FP) mixed in pollen-germinating media and FP), and two methods of pollination (cut-style and stigmatic pollinations). An optimal in vitro pollen germination medium for Phaseolus pollen was developed. Low temperatures (6,9°C) were demonstrated to be necessary for Phaseolus pollen germination. Pollination using a cut-style technique coupled with pregerminated pollen reduced the time for fertilization in the backcrosses of interspecies hybrids by approximately 28 h. This technique improved the success rate of fertilization in wide crosses of Phaseolus designed to introgress genes from wild relatives. [source] Changes in mesophyll anatomy and sink,source relationships during leaf development in Quercus glauca, an evergreen tree showing delayed leaf greeningPLANT CELL & ENVIRONMENT, Issue 5 2003S.-I. MIYAZAWA ABSTRACT Changes in mesophyll anatomy, gas exchange, and the amounts of nitrogen and cell wall constituents including cellulose, hemicellulose and lignin during leaf development were studied in an evergreen broad-leaved tree, Quercus glauca, and in an annual herb, Phaseolus vulgaris. The number of chloroplasts per whole leaf in P. vulgaris increased and attained the maximal level around 10 d before full leaf area expansion (FLE), whereas it continued to increase even after FLE in Q. glauca. The increase in the number of palisade tissue cells per whole leaf continued until a few days before FLE in Q. glauca, but it had almost ceased by 10 d before FLE in P. vulgaris. The radius and height of palisade tissue cells in Q. glauca, attained their maximal levels at around FLE whereas the thickness of the mesophyll cell wall and concentrations of the cell wall constituents increased markedly after FLE. These results clearly indicated that, in Q. glauca, chloroplast development proceeded in parallel with the cell wall thickening well after completion of the mesophyll cell division and cell enlargement. The sink,source transition, defined to be the time when the increase in daily carbon exchange rate exceeds the daily increase in leaf carbon content, occurred before FLE in P. vulgaris but after FLE in Q. glauca. During leaf area expansion, the maximum daily increase in nitrogen content on a whole leaf basis (the maximum leaf areas were corrected to be identical for these species) in Q. glauca was similar to that in P. vulgaris. In Q. glauca, however, more than 70% of nitrogen in the mature leaf was invested during its sink phase, whereas in P. vulgaris it was 50%. These results suggest that Q. glauca invests nitrogen for cell division for a considerable period and for chloroplast development during the later stages. We conclude that the competition for nitrogen between cell division and chloroplast development in the area of expanding leaves can explain different greening patterns among plant species. [source] Slow development of leaf photosynthesis in an evergreen broad-leaved tree, Castanopsis sieboldii: relationships between leaf anatomical characteristics and photosynthetic ratePLANT CELL & ENVIRONMENT, Issue 3 2001S.-I. Miyazawa ABSTRACT Changes in net photosynthetic rate on a leaf area basis and anatomical properties during leaf development were studied in an evergreen broad-leaved tree, Castanopsis sieboldii and an annual herb, Phaseolus vulgaris. In C. sieboldii, surface area of mesophyll cells facing the intercellular air spaces on a leaf area basis (Smes) was already considerable at the time of full leaf area expansion (FLE). However, surface area of chloroplasts facing the intercellular air spaces on a leaf area basis (Sc), and chlorophyll and Rubisco contents on a leaf area basis increased to attain their maximal values 15,40 d after FLE. In contrast, in P. vulgaris, chloroplast number on a leaf area basis, Sc and Smes at 10 d before FLE were two to three times greater than the steady-state levels attained at around FLE. In C. sieboldii, the internal CO2 transfer conductance (gi) slightly increased for 10 d after FLE but then decreased toward the later stages. Limitation of photosynthesis by gi was only about 10% at FLE, but then increased to about 30% at around 40 d after FLE. The large limitation after FLE by gi was probably due to the decrease in CO2 concentration in the chloroplast caused by the increases in thickness of mesophyll cell walls and in Rubisco content per chloroplast surface area. These results clearly showed that: (1) in C. sieboldii, chloroplast development proceeded more slowly than mesophyll cell expansion and continued well after FLE, whereas in P. vulgaris these processes proceeded synchronously and were completed by FLE; (2) after FLE, photosynthesis in leaves of C. sieboldii was markedly limited by gi. From these results, it is suggested that, in the evergreen broad-leaved trees, mechanical protection of mesophyll cells has priority over the efficient CO2 transfer and quick construction of the chloroplasts. [source] Patterns of accumulation of Bean common mosaic virus in Phaseolus vulgaris genotypes nearly isogenic for the I locusANNALS OF APPLIED BIOLOGY, Issue 3 2006M.M. Cadle-Davidson Abstract The I locus of Phaseolus vulgaris is genetically and phenotypically well described, conferring incompletely dominant, temperature-dependent resistance against viruses currently assigned to at least four Potyvirus species. Despite the fact that the resistance allele at this locus, the I gene, has been incorporated into nearly all bean germplasm worldwide, little is known regarding its resistance mechanism. In the present study, P. vulgaris lines nearly isogenic for I were challenged with Bean common mosaic virus (BCMV; genus Potyvirus) in order to investigate at the cellular level the temperature-dependent resistance reaction. Immunolocalisation and confocal laser scanning microscopy were employed to visualise the virus and to identify patterns of BCMV accumulation in resistant, susceptible and heterozygous genotypes. Virus was detected in all three genotypes regardless of temperature, supporting previous findings that BCMV accumulates in protoplasts containing the I allele. Genotype-specific and temperature-specific patterns of virus accumulation suggested a resistance mechanism that depends on host recognition of viral replication and/or local movement. [source] Spectral filters for the control of Botrytis cinereaANNALS OF APPLIED BIOLOGY, Issue 2 2000J S WEST Summary Experiments performed in vitro examined the sporulation of Botrytis cinerea (grey mould) under different spectral distributions. Eighty-three isolates, taken from plants of primula (Primula vulgaris) at different locations throughout the UK, were incubated in the dark, with visible light only and visible plus near-ultraviolet (nUV) light. On average, compared to isolates not exposed to nUV, sporulation was increased 54-fold following illumination with nUV light. No isolates showed complete insensitivity to near ultraviolet. New polyethylene materials with different optical properties were then tested on two typical isolates. A film which removed nUV up to 405 nm, compared to a film with nUV absorption up to 384 nm, resulted in the lowest production of conidia (by 5-fold). The former film was used to clad horticultural polyethylene tunnels in which crops of P. vulgaris and strawberry were grown for two seasons and the incidence of B. cinerea assessed throughout the growth of the crops. The incidence of infection on the P. vulgaris and strawberries was reduced by c. 50% and c. 26% respectively with the nUV blocking film compared to a standard film. The results are discussed in terms of the potential of spectral filters as a novel means of grey mould control in greenhouse-produced crops. [source] Applying a continua landscape approach to evaluate plant response to fragmentation: Primula vulgaris in the Cantabrian mountainsAPPLIED VEGETATION SCIENCE, Issue 4 2009Alicia Valdés Abstract Question: Continua landscape approaches conceptualize the effects of habitat fragmentation on the biota by considering fragmented landscapes as continuous gradients, departing from the view of habitat as either suitable (fragment) or unsuitable (matrix). They also consider the ecological gradients or the ,Umwelt' (species-specific perception of the landscape) to represent the processes that ultimately limit organisms' ability to colonize and persist within habitat remnants. Are these approaches suitable for evaluating the response of plant species to fragmentation? Location: Fragmented mid-elevation temperate forests, Cantabrian range, Spain. Methods: The presence, abundance and demographic structure of populations of the perennial herb Primula vulgaris were sampled across a continuous extent of 100 ha, subdivided into 400 50 m × 50 m sampling units. These variables were related to forest availability, forest subdivision and edge density, topography and the spatial clumpiness of populations (a measure of plant dispersal constraints and, hence, a major surrogate of plant Umwelt). Results: Fragmentation processes, especially habitat loss, negatively affect P. vulgaris, with a stronger effect on presence than on abundance and demography. Despite the importance of habitat availability, P. vulgaris does not occupy all potentially suitable forest habitat, mostly owing to dispersal constraints. A positive effect of slope on plant presence also suggests some effect of habitat quality in determining establishment and occupancy of forest landscape. Conclusions: Within-habitat dispersal constraints are as important as forest fragmentation in determining the landscape-scale distribution of P. vulgaris. By assessing the relative role of the diverse fragmentation processes, and of the species' landscape perception, a continua landscape approach proves to be a valuable tool for predicting plant response to landscape change. [source] Host-mediated induction of ,-amylases by larvae of the Mexican bean weevil Zabrotes subfasciatus (Coleoptera: Chrysomelidae: Bruchinae) is irreversible and observed from the initiation of the feeding periodARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 4 2010Thaís D. Bifano Abstract Larvae of Zabrotes subfasciatus secrete , -amylases that are insensitive to the , -amylase inhibitor found in seeds of Phaseolus vulgaris. By analyzing amylase activities during larval development on P. vulgaris, we detected activity of the constitutive amylase and the two inducible amylase isoforms at all stages. When larvae were transferred from the non , -amylase inhibitor containing seeds of Vigna unguiculata to P. vulgaris, the inducible , -amylases were expressed at the same level as in control larvae fed on P. vulgaris. Interestingly, when larvae were transferred from seeds of P. vulgaris to those of V. unguiculata, inducible , -amylases continued to be expressed at a level similar to that found in control larvae fed P. vulgaris continuously. When 10-day-old larvae were removed from seeds of V. unguiculata and transferred into capsules containing flour of P. vulgaris cotyledons, and thus maintained until completing 17 days (age when the larvae stopped feeding), we could detect higher activity of the inducible , -amylases. However, when larvae of the same age were transferred from P. vulgaris into capsules containing flour of V. unguiculata, the inducible , -amylases remained up-regulated. These results suggest that the larvae of Z. subfasciatus have the ability to induce insensitive amylases early in their development. A short period of feeding on P. vulgaris cotyledon flour was sufficient to irreversibly induce the inducible , -amylase isoforms. Incubations of brush border membrane vesicles with the , -amylase inhibitor 1 from P. vulgaris suggest that the inhibitor is recognized by putative receptors found in the midgut microvillar membranes. © 2010 Wiley Periodicals, Inc. [source] | ||||||||||