Karambole (Averrhoa carambola L.)

The carambola (Averrhoa carambola L., family Oxalidaceae) is believed to have originated in Sri Lanka and the Moluccas but it has been cultivated in southeast Asia and Malaysia for many centuries. The evergreen tree is slow-growing, has a rounded crown and reaches 6 to 9 m in height. The 5- to 6-angled fruits (6 to 15 cm long and up to 9 cm wide) have thin, waxy, orange-yellow skin and juicy, yellow flesh. The fruit has a more or less pronounced oxalic acid odor and the flavor ranges from very sour to middle sweetish. The carambola is a tropical and subtropical tree, it can tolerate freezing temperature (?2°C) for short periods and sustain little damage. Trees can be propagated by seed, grafting, budding, and air layering. Tissue culture propagation has met only limited success. Plant spacing varies with growing region and cultural practices. Tree training is practiced intensively in different countries. Harvest timing and postharvest handling are critical to successful marketing of fresh fruit. Carambola is a nonclimateric fruit. Growers carefully harvest fruit by hand at color break — light green fruit with yellow color. The storage conditions should be 5 to 10°C and 85 to 95% relative humidity. Most carambola fruit is eaten fresh, used in salads, desserts, and cooked as star-shaped slices; fruit can also be dried, canned and frozen. The leaves have been eaten as a substitute for sorrel. Commercial production occurs in Taiwan, Malaysia, southern China, the Philippines, Australia, USA (Florida, Hawaii), Brazil, Suriname and Guyana. Production and consumption appears on the rise throughout the world and will most likely increase as selection and breeding for superior tasting cultivars with improved handling characteristics and storage conditions are found.     

Modelling land cover transitions: A solution to the problem of spatial dependence in data

Raster-based spatial land cover transition models (LCTMs) are widely used in landscape ecology. However, many LCTMs do not account for spatial dependence of the input data, which may artificially fragment the output spatial configuration. We demonstrate the consequences of ignoring spatial dependence, thus assigning probabilities randomly in space, using a simple LCTM. We ran the model from four different initial conditions with distinct spatial configurations and results indicated that, after 20 simulation steps, all of them converged towards the spatial configuration of the random data set. From an ecological perspective this is a serious problem because ecological data often exhibit distinct spatial configuration related to ecological processes. As a solution, we propose an approach (region approach) that accounts for spatial dependence of LCTM input data. Underlying spatial dependence was used to apply spatial bias to probability assignment within the model. As a case study we applied a region approach to a Vegetation Transition Model (VTM); a semi-Markovian model that simulates forest succession. The VTM was applied to approximately 500,000 ha of boreal forest in Ontario, at 1 ha pixel resolution. When the stochastic transition algorithms were applied without accounting for spatial dependence, spatial configuration of the output data became progressively more fragmented. When the VTM was applied using the region approach to account for spatial dependence output fragmentation was reduced. Accounting for spatial dependence in transition models will create more reliable output for analyzing spatial patterns and relating those patterns to ecological processes.This revised version was published online in May 2005 with corrections to the Cover Date.     

Characterizing historical and modern fire regimes in Michigan (USA): A landscape ecosystem approach

We studied the relationships of landscape ecosystems to historical and contemporary fire regimes across 4.3 million hectares in northern lower Michigan (USA). Changes in fire regimes were documented by comparing historical fire rotations in different landscape ecosystems to those occurring between 1985 and 2000. Previously published data and a synthesis of the literature were used to identify six forest-replacement fire regime categories with fire rotations ranging from very short (<100 years) to very long (>1,000 years). We derived spatially-explicit estimates of the susceptibility of landscape ecosystems to fire disturbance using Landtype Association maps as initial units of investigation. Each Landtype Association polygon was assigned to a fire regime category based on associations of ecological factors known to influence fire regimes. Spatial statistics were used to interpolate fire points recorded by the General Land Office. Historical fire rotations were determined by calculating the area burned for each category of fire regime and dividing this area by fifteen (years) to estimate area burned per annum. Modern fire rotations were estimated using data on fire location and size obtained from federal and state agencies. Landtype Associations networked into fire regime categories exhibited differences in both historical and modern fire rotations. Historical rotations varied by 23-fold across all fire rotation categories, and modern forest fire rotations by 13-fold. Modern fire rotations were an order of magnitude longer than historical rotations. The magnitude of these changes has important implications for forest health and understanding of ecological processes in most of the fire rotation categories that we identified.This revised version was published online in May 2005 with corrections to the Cover Date.     

Callus induction and plant regeneration from cotyledonary explants of ash gourd (Benincasa hispida L.)

A protocol for the production of complete plantlets through multiple shoots from the cotyledon-derived calli of ash gourd (Benincasa hispida L.) is described. The embryos were excised from mature seeds and cultured on Murashige and Skoog (MS) medium supplemented with 6-benzylaminopurin (BAP, 1–5 μM). After 10 days the well-developed green cotyledons from the growing embryos were isolated and cultured on MS medium fortified with 2,4-D (1–6 μM). The cultured cotyledons gave rise to luxuriantly growing calli after 6 weeks. These calli were subcultured on MS medium supplemented with various concentrations of BAP (1–6 μM) alone or in combination with naphthalene acetic acid (NAA, 0.2 and 0.5 μM) for regeneration. The regenerated shoots were multiplied and rooted on quarter strength MS medium supplemented with indole-3-butyric acid or NAA (1–5 μM). The rooted shoots were transplanted to soil with 90% success.     

Untersuchungen zur Übertragung von Clavibacter michiganensis ssp. sepedonicus auf gesunde Kartoffelknollen

Zusammenfassung In den Jahren 1999 bis 2003 wurde in Freiland-, Klimakammer- und Lagerungsversuchen überprüft, ob ein Risiko für die Übertragung des Erregers der Bakteriellen Ringfäule der Kartoffel (Clavibacter michiganensis ssp. sepedonicus) besteht, wenn (a) gesunde Kartoffelknollen in Kontakt mit Maschinen und Geräten kommen, die mit dem Erreger kontaminiert sind (indirekter Kontakt) und (b) gesunde Kartoffelknollen direkt in Kontakt mit infizierten Knollen kommen (direkter Kontakt). Nach indirektem Kontakt konnte nur beim nachfolgenden Anbau der kontaminierten Knollen in der Klimakammer Befall in Kraut und Knollen festgestellt werden. Im Freiland konnte der Erreger, auch bei wiederholtem Nachbau der geernteten Knollen, nicht nachgewiesen werden. Nach direktem Kontakt und nachfolgendem Anbau der kontaminierten Knollen in der Klimakammer und im Freiland, wurde der Erreger in allen Fällen in den geerntete Knollen nachgewiesen. Befall im Kraut wurde nur in dem Klimakammerversuch und in einem Freilandversuch ermittelt. Wurden durch direkten Kontakt kontaminierte Knollen eingelagert, konnte der Erreger in allen untersuchten Knollen festgestellt werden. Insgesamt besteht ein hohes Risiko, dass gesunde Knollen infiziert werden, wenn oberflächliche Kontaminationen mit dem Erreger erfolgen. Die Wahrscheinlichkeit von Infektionen steigt mit zunehmender Kontaminationsstärke.     

新一代植酸酶的经济效益

现已证明，在酵母中产生的一种新型的6-植酸酶比其他在市场上供应的植酸酶的效率至少高20％。因为6-植酸酶与其他商品化的植酸酶相比，可进一步减少无机磷源的使用，从而降低生产成本以及磷的污染。     

Computed tomography dacryocystography evaluation of the nasolacrimal apparatus

Computed tomography-dacryocystography (CT-DCG) was used to evaluate the nasolacrimal system in four patients (three dogs and one horse) that were admitted for evaluation of chronic epiphora, facial swelling, or facial trauma. The four patients are reviewed and the technique for performing CT-DCG is described. Additionally, the indications for this procedure are discussed. CT-DCG is advantageous because cross-sectional imaging provides superior resolution of the nasolacrimal apparatus and the relatively long, small-diameter, bony nasolacrimal canal in most veterinary patients.     

Material in the middle ear of dogs having magnetic resonance imaging for investigation of neurologic signs

The aim of this study was to determine the prevalence and potential significance of finding material in the middle ear of dogs having magnetic resonance (MR) imaging. Of 466 MR studies reviewed, an increased signal was identified in the tympanic bulla in 32 (7%) dogs. Cavalier King Charles spaniels, Cocker spaniels, Bulldogs, and Boxers were over-represented compared to the population of dogs having MR imaging. Five (16%) dogs had definite otitis media and one (3%) had a meningioma invading the middle ear. Of the remaining dogs, 13 (41%) had possible otitis media and 13 (41%) had neurologic conditions apparently unrelated to otitis media. The most common appearance of material in the middle ear was isointense in T1-weighted images and hyperintense in T2-weighted images. There was no apparent correlation between the signal characteristics of the material and the diagnosis. Enhanced signal after gadolinium administration was observed affecting the lining of the bulla in dogs with otitis media and in dogs with unrelated neurologic conditions. In dogs without clinical signs of otitis media, finding an increased signal in the middle ear during MR imaging may reflect subclinical otitis media or fluid accumulation unrelated to inflammation. Brachycephalic dogs may be predisposed to this condition.     

Diagnosis of skeletal injuries in Chelonians using computed tomography.

Computed tomography (CT) was used to diagnose the cause of lameness in a radiated tortoise (Geochelone radiata) and to determine the extent of shell and skeletal trauma in two snapping turtles (Chelydra serpentina). The radiated tortoise's lameness was ultimately attributed to luxation of the right-shoulder joint that was not detected during plain film radiography. Axial and appendicular fractures were identified in one of the snapping turtles that were not detected during plain film radiography. In each patient, the information obtained during CT provided important diagnostic, therapeutic, or prognostic information.