Thorns as Induced Mechanical Defense in a Long-Lived Shrub (Hormathophylla spinosa, Cruciferae)

Ecology ◽  
2002 ◽  
Vol 83 (4) ◽  
pp. 885 ◽  
Author(s):  
Jose M. Gomez ◽  
Regino Zamora
Keyword(s):  
Mechanical Defense

Theory and practice of instrument sterilization

1936 ◽  
Vol 32 (10) ◽  
pp. 1274-1275
Author(s):  
G. Sobernheim
Keyword(s):  
Theory And Practice ◽  
Garden Soil ◽  
Standard Object ◽  
Mechanical Defense ◽  
Number Of Authors

The author considers the use of garden soil as a standard object, which is the most unsuitable material for this purpose, as the reason for the unequal and even contradictory results obtained by a number of authors when checking the sterilizing effect of a boiling 1-2% solution of soda; the "native" spores contained in it are more persistent than spores obtained from the respective crops, since lumps of earth are a good mechanical defense for them.

scholarly journals Modelling and Manufacturing of Progressive die for Mechanical Press Operations

2021 ◽  
Vol 12 (3) ◽  
pp. 3662-3671
Author(s):  
V.Venkatrami Reddy Et.al
Keyword(s):  
Sheet Metal ◽  
Cost Reduction ◽  
Manufacturing Industries ◽  
Metal Working ◽  
Cnc Machine ◽  
Working Process ◽  
Progressive Die ◽  
Mechanical Press ◽  
Part Program ◽  
Mechanical Defense

A progressive die is a type of die in which multiple operations performed in a single stroke, which was mostly used in sheet metal operations. The working process of sheet metal is widely used in all manufacturing industries such as mechanical, defense and automotive etc. The key advantage of metal working process involves enhancement of production rate and cost reduction. This paper is aimed to develop a multi-functional die which can perform simultaneously both punching and blanking operations in one stroke. The present work is mainly focused on modeling and manufacturing of the die components, where PRO-E was used for modelling and FANUC controlled CNC machine was used to execute and prepared part program.

Water content and reserve allocation patterns within the bulb of the perennial geophyte red squill (Liliaceae) in relation to the Mediterranean climate

Botany ◽  
2008 ◽  
Vol 86 (3) ◽  
pp. 291-299 ◽  
Author(s):  
Sharaf Al-Tardeh ◽  
Thomas Sawidis ◽  
Barbara-Evelin Diannelidis ◽  
Stylianos Delivopoulos
Keyword(s):  
Water Content ◽  
Mediterranean Climate ◽  
Late Summer ◽  
Adaptive Strategy ◽  
Active Centre ◽  
Urginea Maritima ◽  
Outer Covering ◽  
Mechanical Defense ◽  
Allocation Patterns ◽  
The Mediterranean

The patterns of water content and reserve allocation in the bulb parts of red squill ( Urginea maritima (L.) Baker) and the plant’s adaptive strategy to Mediterranean climate (Crete, Greece) were investigated. The different bulb parts serve varying ecological functions in terms of their resources and their importance for these functions. The basal plate is the active centre, developing one or two apical meristems and roots in autumn, as well as the flowering bud in late summer. The middle of the bulb (approximately the third bulb scale) stores the resources and the tunics (the outer covering structures) that provide mechanical defense. The water content and reserve allocation patterns synchronize the plant’s phenological development with the seasonality of the Mediterranean climate. The adaptive strategies are based on the development of a deciduous semisubterranean life form primarily for the avoidance of drought, herbivores, and other environmental hazards, as well as nutrient shortage. The presence of cells containing lipids, polysaccharides, raphides, water, mucilage, bufadienolides, the presence of sclerenchyma, the tightly packed epidermis, and the presence of the tunics facilitate this.

scholarly journals Associations of Two Ecologically Significant Social Insect Taxa in the Litter of an Amazonian Rainforest: Is There a Relationship between Ant and Termite Species Richness?

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Amy L. Mertl ◽  
James F. A. Traniello ◽  
Kari Ryder Wilkie ◽  
Reginaldo Constantino
Keyword(s):  
Species Richness ◽  
Ecological Factors ◽  
Food Sources ◽  
Nest Sites ◽  
Ant Predation ◽  
Mechanical Defense ◽  
Amazonian Rainforest ◽  
Ecological Dominance ◽  
Ant Diversity ◽  
Neotropical Ants

In spite of the ecological dominance of Neotropical ants and termites, little is understood about how their interactions influence their species richness and distribution. We surveyed ground-dwelling termite and ant species in a primary rainforest in Ecuador and analyzed ecological correlates of diversity. Termite richness was positively correlated with ant richness and abundance of twig-nesting ants. We found no evidence of competition for twigs between termites and ants. No ecological factors were correlated with termite diversity although elevation and twig and log abundance influenced ant diversity. When ant richness was compared to the richness of termites employing different predator defenses, a positive correlation was found with soldierless termites, but not genera employing chemical or mechanical defense. Our results suggest that multiple ecological factors influence ant and termite diversity, and that ant predation on termites may have a greater effect than competition between ant and termites for nest sites and food sources.

scholarly journals Asteraceae Paradox: Chemical and Mechanical Protection of Taraxacum Pollen

Insects ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 304 ◽  
Author(s):  
Maryse Vanderplanck ◽  
Hélène Gilles ◽  
Denis Nonclercq ◽  
Pierre Duez ◽  
Pascal Gerbaux
Keyword(s):  
Bombus Terrestris ◽  
Chemical Defenses ◽  
Physiological Effects ◽  
Plant Selection ◽  
Toxic Compounds ◽  
Offspring Production ◽  
Pollen Feeding ◽  
Mechanical Defense ◽  
Chemical Traits ◽  
Floral Cues

Excessive pollen harvesting by bees can compromise the reproductive success of plants. Plants have therefore evolved different morphological structures and floral cues to narrow the spectrum of pollen feeding visitors. Among “filtering” mechanisms, the chemical and mechanical protection of pollen might shape bee-flower interactions and restrict pollen exploitation to a specific suite of visitors such as observed in Asteraceae. Asteraceae pollen is indeed only occasionally exploited by generalist bee species but plentifully foraged by specialist ones (i.e., Asteraceae paradox). During our bioassays, we observed that micro-colonies of generalist bumblebee (Bombus terrestris L.) feeding on Taraxacum pollen (Asteraceae) reduced their pollen collection and offspring production. Bees also experienced physiological effects of possible defenses in the form of digestive damage. Overall, our results suggest the existence of an effective chemical defense in Asteraceae pollen, while the hypothesis of a mechanical defense appeared more unlikely. Pre- and post-ingestive effects of such chemical defenses (i.e., nutrient deficit or presence of toxic compounds), as well as their role in the shaping of bee-flower interactions, are discussed. Our results strongly suggest that pollen chemical traits may act as drivers of plant selection by bees and partly explain why Asteraceae pollen is rare in generalist bee diets.

Pod and seed defensive coloration (camouflage and mimicry) in the genus Pisum

2015 ◽  
Vol 62 (1-2) ◽  
pp. 39-51 ◽  
Author(s):  
Iris Aviezer ◽  
Simcha Lev-Yadun
Keyword(s):  
Seed Coat ◽  
Coat Color ◽  
Grazing Pressure ◽  
Legume Species ◽  
Seed Coat Color ◽  
Color Patterns ◽  
Annual Species ◽  
Wild Type ◽  
Mechanical Defense ◽  
Small Genus

The small genusPisumis composed of two annual species,P.fulvumand the domesticated peaP.sativum. The domesticated pea has two main wild-type taxa:P.elatiusandP.humile. Members of the genusPisumare not well defended from herbivory by high levels of toxins like the seeds of many other legume species. We studied the color patterns in the pods and seeds of these three wild taxa (P.fulvum,P.elatiusandP.humile) in order to examine their potential for defensive coloration (camouflage and Batesian mimicry). All three taxa are polymorphic concerning pod and seed coloration. The mature pods of many individuals ofP.humileandP.elatiusmimic aposematic caterpillars, but some are plain green. The pods of some individuals ofP.elatiushave a zigzag or straight red marking along them that resembles the conspicuous dorsal markings of the local common venomous viper, potentially mimicking it. The pods of many individuals ofP.fulvumhave dark blotches that when compared to such patterns in animals, potentially function as camouflage. The seeds of all three species are camouflaged by either: (1) color matching with that of soil (especiallyP.fulvumandP.elatius), (2) disruptive coloration (especiallyP.humile), (3) variability in seed-coat color that may undermine the use of search images by visually oriented granivores that look for cryptic seeds (all taxa). The mature pods ofP.fulvumare also defended in many inflorescences by degenerated flowers that develop into sharp thorns. It seems that this species is still in the process of evolving this mechanical defense as the response to millennia of strong grazing pressure.

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