QUANTIFICATION OF MANDIBULAR WEAR OF FEMALE ALFALFA LEAFCUTTER BEES, MEGACHILE ROTUNDATA (F.) (HYMENOPTERA: MEGACHILIDAE), BY IMAGE ANALYSIS

1993 ◽  
Vol 125 (1) ◽  
pp. 93-99 ◽  
Author(s):  
E.G. Kokko ◽  
B.D. Schaber ◽  
T. Entz
Keyword(s):  
Image Analysis ◽  
Digital Image Analysis ◽  
Megachile Rotundata ◽  
Wear Analysis ◽  
Southern Alberta ◽  
Before And After ◽  
Alfalfa Seed ◽  
Leafcutter Bee ◽  
Mandibular Teeth ◽  
Seed Yields

AbstractIn southern Alberta, alfalfa seed yields are related to the amount of pollination that occurs before mid-August by the major pollinator, the alfalfa leafcutter bee, Megachile rotundata (F.). Cutting the leaves causes wear to the bee’s mandibular teeth and could reduce the bee’s pollination efficiency and, ultimately, seed production. A method is described for employing digital image analysis to measure mandibular tooth areas for alfalfa leafcutter bees. The method is relatively quick and has high precision and repeatability. This method was used to measure the area of the mandibular teeth for leafcutter bees, before and after foraging in alfalfa seed fields, to evaluate differences in mandibular wear. Analysis of mandibles showed that foraging leafcutter bees collected in late July had significantly smaller tooth areas than pre-foraging bees collected prior to release in June.

THE EFFECT OF SPRING BURNING OF SEED ALFALFA FIELDS ON LEAF CHARACTERISTICS AND ON MANDIBULAR WEAR OF FEMALE LEAFCUTTER BEES [MEGACHILE ROTUNDATA (F.)] (HYMENOPTERA: MEGACHILIDAE)

1993 ◽  
Vol 125 (5) ◽  
pp. 881-886 ◽  
Author(s):  
B.D. Schaber ◽  
E.G. Kokko ◽  
T. Entz ◽  
K.W. Richards
Keyword(s):  
Image Analysis ◽  
Seed Yield ◽  
Consistent Difference ◽  
Analysis Method ◽  
Megachile Rotundata ◽  
Image Analysis Method ◽  
Leaf Characteristics ◽  
Leafcutter Bee ◽  
Seed Yields

AbstractIncreased seed yields often result when alfalfa fields are burned in spring. The main pollinator of seed alfalfa in Alberta is the alfalfa leafcutter bee, Megachile rotundata (F.), that cuts pieces of leaves to build thimble-like cells. One hypothesis for increased seed yield is that alfalfa leaves from burned fields may be easier for the bees to cut. Cutting of leaf pieces causes progressive wear to the mandibles, which could decrease bee efficiency, resulting in reduced pollination and lower seed yields. An image analysis method was used to measure the mandibular wear of leafcutter bees from burned and unburned alfalfa fields. No consistent difference in the amount of wear between bees foraging in burned or unburned fields was found.

scholarly journals Anatomical Characteristics of Garcinia lucida (Vesque) and Scorodophloeus zenkeri (Harms) Wood and Debarking Response in the South Region Cameroon

2017 ◽  
Vol 6 (4) ◽  
pp. 132
Author(s):  
Marie Caroline Momo Solefack ◽  
Hans Beeckman ◽  
Lucie Felicite Temgoua ◽  
Ghislain Kenguem Kinjouo
Keyword(s):  
Image Analysis ◽  
Cross Section ◽  
Digital Image ◽  
Digital Image Analysis ◽  
Analysis Software ◽  
Anatomical Changes ◽  
Image Analysis Software ◽  
Conductive Zone ◽  
Before And After

The aim of this work was to investigate the possible anatomical changes of Garcinia lucida and Scorodophloeus zenkeri after the removal of their bark. Debarking was done on individuals of each species at 1.30 m from the soil. The wound was rectangular in shape with 30 cm side. There was a follow-up every three months for nine months during which the survival and rate of regeneration of the bark were recorded. A block of cube was cut from the regenerated and intact wood of species for microtomy and microscopy activities. On the cross-section of each wood, vessel features like density and diameter were measured before and after wounding. Semi-automatic measurements were made using the SpectrumSee digital image analysis software. In the wood of the two species, it appeared that the density of the vessels before debarking was significantly comparable to the density after debarking, while the diameter of vessels in the regenerated wood was smaller. The cambial area increased slightly in the rainy season for all species. After nine months all the species started the restoration of their conductive zone. G. lucida heals its wound more rapidly than S. zenkeri.

EFFECT OF ENVIRONMENT AND EQUIPMENT ON PRODUCTIVITY OF ALFALFA LEAFCUTTER BEES (HYMENOPTERA: MEGACHILIDAE) IN SOUTHERN ALBERTA, CANADA

1996 ◽  
Vol 128 (1) ◽  
pp. 47-56 ◽  
Author(s):  
K.W. Richards
Keyword(s):  
Environmental Variables ◽  
Total Cell ◽  
Significant Positive Effect ◽  
Megachile Rotundata ◽  
Southern Alberta ◽  
Temperature Heat ◽  
Leafcutter Bee ◽  
Nesting Material ◽  
Higher Temperature ◽  
Positive Effect

AbstractFour indicators of productivity and quality for the alfalfa leafcutter bee, Megachile rotundata (Fab.), were examined over a 3-year period and the influence of different shelter designs, nesting materials, and 34 environmental variables evaluated. A higher percentage of cocoons per total cells was produced in polystyrene nesting material than in pinewood nesting material. Both nesting materials had similar percentages of tunnels capped or containing cells and total numbers of cells per hive. Shelters with conspicuous orientation patterns or silhouettes had more tunnels capped per hive, tunnels with cells, and greater total cell production per hive than did other shelter designs. The time of maximum bee production varied greatly among the 3 years. Many environmental variables, especially those associated with higher temperature, heat units, and mean actual temperature, had a significant positive effect on bee productivity and cell quality. The information contained in this study may help delineate those climatic areas where this valuable alfalfa pollinator can be most effective, and may assist beekeepers in making management decisions that will improve their operations.

Quackgrass (Elytrigia repens) Interference and Control in Seed Alfalfa (Medicago sativa)

1993 ◽  
Vol 7 (1) ◽  
pp. 58-64 ◽  
Author(s):  
James R. Moyer ◽  
G. Bruce Schaalje
Keyword(s):  
Seed Yield ◽  
Hyperbolic Model ◽  
Threshold Density ◽  
Economic Threshold ◽  
Elytrigia Repens ◽  
Southern Alberta ◽  
Herbicide Treatments ◽  
Alfalfa Seed ◽  
Seed Yields ◽  
And Control

Alfalfa seed yield and quackgrass density were measured in seven irrigated fields in southern Alberta to assess the effect of quackgrass on seed yield. Six herbicides were tested to determine their effect on quackgrass growth and accompanying alfalfa seed yield. The effect of quackgrass on seed yield was adequately described by a hyperbolic model. Quackgrass densities of 50 and 100 heads per m2reduced seed yields by 56 and 74%, respectively. The economic threshold density was 3 quackgrass heads per m2. The most effective herbicide treatments, quizalofop and propaquizafop, resulted in good initial quackgrass suppression and yield increases similar to those predicted by the hyperbolic model.

Morphometric analysis of cellular interactions with the endothelium during the development of arterial lesions using Scanning Electron Microscopy and digital image analysis

1987 ◽  
Vol 45 ◽  
pp. 918-919
Author(s):  
M.E. Rosenfeld ◽  
C. Karboski ◽  
M.F. Prescott ◽  
P. Goodwin ◽  
R. Ross
Keyword(s):  
Electron Microscopy ◽  
Image Analysis ◽  
Quantitative Data ◽  
Digital Image Analysis ◽  
Lower Cost ◽  
Matched Control ◽  
Digital Analysis ◽  
Cellular Interactions ◽  
Arterial Lesions ◽  
Scanning Electron

Previous research documenting the chronology of the cellular interactions that occur on or below the surface of the endothelium during the initiation and progression of arterial lesions, primarily consisted of descriptive studies. The recent development of lower cost image analysis hardware and software has facilitated the collection of high resolution quantitative data from microscopic images. In this report we present preliminary quantitative data on the sequence of cellular interactions that occur on the endothelium during the initiation of atherosclerosis or vasculitis utilizing digital analysis of images obtained directly from the scanning electron microscope. Segments of both atherosclerotic and normal arteries were obtained from either diet-induced or endogenously (WHHL) hypercholesterolemic rabbits following 1-4 months duration of hypercholesterolemia and age matched control rabbits. Vasculitis was induced in rats following placement of an endotoxin soaked thread adjacent to the adventitial surface of arteries.

Digital Image Analysis of the Larynx

2000 ◽  
Vol 10 (2) ◽  
pp. 7-9
Author(s):  
Yaser Natour ◽  
Christine Sapienza ◽  
Mark Schmalz ◽  
Savita Collins
Keyword(s):  
Image Analysis ◽  
Digital Image ◽  
Digital Image Analysis
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