The Effect Of Surface Residues On Weeds

The Effect Of Surface Residues On Weeds
Crop residue may be kept in the field in both CT and NT systems (CT+Res and NT+Res,
respectively). In CT+Res the residue is incorporated into the soil, with the depth of mixing
dependent upon type of tillage. Although incorporated residue may affect weeds via altered nutrient
dynamics, the effects will be highly dependent on the type of tillage used, the carbon to nitrogen
ratio of the residue, the type of soil, and the environment – it will therefore be difficult to extract
useful generalities (Liebman and Mohler, 2001, p. 236). Consequently, in this review we focus on
the effects of surface residues on weeds.
3.1 Residue – Seedbank
3.1.1 Losses
3.1.1.1 Germination
Surface residues can affect seed germination via physical and chemical ... Show more content on
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As such, decreased weed seed germination due to insufficient light–availability is likely not a major
advantage of residue retention.
Surface residue decreases the daily maximum soil temperature but has little effect on the daily
minimum (Teasdale and Mohler, 1993) resulting in two changes: cooler average soil temperatures
and less drastic fluctuations. Most agronomic crops and many weeds require soil temperatures above
a certain threshold in order to germinate – the lower soil temperatures under surface residue would
therefore delay germination of both. This delayed germination and resulting shorter growing season
of the crop can reduce yield; as such it is important to find the amount of residue which optimizes
yield rather than weed control (Wicks et al., 1994). In addition to later germination, some weed
species' germination is enhanced by larger temperature fluctuations (Liebman and Mohler, 2001, p.
239); the buffered soil temperature could therefore reduce germination rates.
Surface residue will conserve soil moisture – how this affects germination rates will depend on the
environment. In water–limited environments, residue may promote germination while in wetter
conditions it may have little effect. This is exemplified by a study done in Zimbabwe, where residue
was more effective in suppressing weeds in wetter sites (Ngwira et al., 2014).
Allelopathy is the phenomenon in which a plant produces biochemicals which affect the
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Interdependence Between the Species
INTERDEPENDENCE BETWEEN THE SPECIES INTERACTION BETWEEN PLANTS AND
ANIMALS: Animals are depending upon plants for their food shelter and also for various things.
ANIMALS HELP PLANTS IN DIFFERENT WAYS 1.Many animals are involved in the pollination
in plants. 2.Fruits and seeds of many plants are dispersed by animals 3.Decomposers convert organic
substances into inorganic substances so that plants can absorb them easily. SPECIES
INTERACTION All types of relationship between organisms can be divided into two 1)Positive
interaction–which is beneficial to one or both partners. These include a) commensalism b)proto co–
operation c) mutualism 2)Negative interaction–which is harmful to one or more of the participants.
These include ... Show more content on Helpwriting.net ...
2.Epiphytes and epizoans: Epiphytes are plants that grow perched on other plants only as support
and not for food and water. They are provided with special roots called velamin roots, which can
take up water from the moisture. Epizoans are plants that grow on the body of animals. Eg the green
algae grow on the long, grooved hairs of the sloth. Sucker fish attaches itself to the body of a shark.
A commensal that lives inside the body of the host is referred to as endocommensal. 1.Some
saprophytic fungi and bacteria live within the tissues and cavities of higher plants and animals.
Some microbes are seen in the lower intestines of animals.(Here they are not taking anything from
the host's body) 2.Termite nests provide ecologic niches for more than a 100 species of other
animals such as ants, beetles and millipeds. 3.A oyster crab, Pinnothers ostreum is found in the
mantle cavity of the oyster. In addition to shelter it also gets food from the host molluscs, oyster
without causing any harm. PROTOCOOPERATION :–It is a short step ahead of commensalism and
cooperation. In this relationship, both organisms gain by the association and are mutually
benefited(facultative mutualism) Eg the Red billed Oxpecker form protocooperation with Black
Rhinoceros– the bird feed on the parasites sticking on the skin of the rhinoceros relieving him of the
parasites, and inturn obtaining

Effects Of Depth On Algal Growth
Lynne Miranda
OCB Lab Experiment
04/17/15
The Effects of Depth on Algal Growth in the Biscayne Bay.
Introduction
Biscayne Bay is located in South Florida and is home to many terrestrial and aquatic organisms.
Over the years, humans have populated the land around Biscayne Bay, which has greatly altered the
water quality. In a study done in 2011, anthropogenic affects in the bay were measured by testing for
an overabundance of nutrients in the water (Carey et al, 2011). This is just one of the many studies
that shows how and why the Biscayne Bay is affected by human activities. A major concern with the
increase in nutrient to the water is that it leads to an accumulation of algae, which ultimately causes
a surge in algal bloom (Levinton, 2013).
Many studies around the world show the detrimental affects of harmful algal blooms, or HAB for
short, and directly link the runoff of nutrients into the water as the key contributor to its frequency.
An example of a study done in estuaries around New York showed that an increase in macro green
algae, which is also found in Biscayne Bay, increases the growth of several other forms of harmful
algae (Tang, 2011). In a more recent study conducted in 2013, Biscayne Bay was shown to have an
increase in green macro algal blooms that are also linked to nutrient runoff in the bay and smother
the sea grass habitats (Vides et al, 2013). Biscayne Bay is said to hold nutrient–rich sediment
(Carnehan et al., 2009).
Algal blooms are responsible

Allelopathy Research Paper
Briana Heck
Allopathy of Black Walnuts and Sunflowers The term allelopathy is from the Greek–derived
compounds allelo and pathy meaning "mutual harm" or "suffering". Allelopathy refers to the
beneficial or harmful effects of one plant on another plant, both crops and weeds, from the release of
a biochemical, known as allelochemicals, from plant parts. Allelochemicals are a subset of
secondary metabolites not required for growth and development of the allelopathic organism.
Allelochemicals with negative allelopathic effects are an important part of plant defense against
animals that only eat plants. Black walnuts are grown mostly for its wood and nuts and are often
found growing on landscape sites where they serve as shade trees. When certain other plants are
planted near or under this shade tree they tend to yellow, wilt and die. This decline occurs because
the walnut tree produces a ... Show more content on Helpwriting.net ...
Like synthetic herbicides, there is no common mode of action or physiological target site for all
allelochemicals. However, known sites of action for some allelochemicals include cell division,
pollen germination, nutrient uptake, photosynthesis, and specific enzyme function. Allelopathic
inhibition is complex and can involve the interaction of different classes of chemicals and mixtures
of different compounds sometimes having a greater allelopathic effect than individual compounds
alone.
Allelopathic chemicals or allelochemicals can also persist in soil, affecting both neighboring plants
as well as those seedlings. Although derived from plants, allelochemicals may be more
biodegradable than traditional herbicides, but allelochemicals may also have undesirable effects on
non–target species. Allelopathic chemicals could be used as a pesticide if scientists can figure out
how to control the chemicals. Selective activity of tree allelochemicals on crops and other plants has
also been

Invasive Species Managment: The Greater Everglades Ecosystem
Invasive Species The world is under attack; by aliens from our own planet. These aliens are known
as invasive species. Government agencies such as the Environmental Protection Agency (EPA) and
the Department of Natural Resources (DNR) have identified invasive species as living organisms
that are not native to an ecosystem and their introduction can cause harm to the environment,
infrastructure, and people. When these creatures are in their natural ecosystem they can be held in
check by predators and other organisms that have evolved to deal with them. Without these
opponents invasive species can and will cause economic and biological damage to the area they are
introduced to. Invasive species can affect anyone and anything and they must ... Show more content
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If something is not done soon the cost of damages will continue to climb. Invasive species don't just
cause monetary damage, they can completely disrupt and destroy ecosystems. Invasive predators
like the brown tree snake can hunt native species to extinction because these species have not
evolved defences against them. Even herbivores can cause indirect damage by feeding on the same
plants as native herbivores therefore taking away their food sources. Plants can cause damage as
well. Through various strategies they can take over the land where native plants would normally
grow diminishing native plant populations. No matter what kind of creature an invasive species is it
can still cause damage.
Florida Everglades Some places are hit harder than others. One of the hardest hit areas is the Florida
Everglades. The Greater Everglades Ecosystem is a region of the tropical wetlands south of Orlando
Florida in the Florida watershed and it spans roughly 11,000 square miles (L. Perez, telephone
interview, February 26, 2014). The Everglades used to be twice that size but much of it was
redeveloped by humans for agricultural land to grow sugarcane (Babbit, 1994). The everglades is
sometimes referred to as the "River of Grass" due to the water slowly flowing through vast
grassland. The source of the water that has created the everglades comes from Lake Okeechobee
100 miles away in central

Allelopathy Affects Germination of Radish Seeds Essay
Introduction This experiment is designed to test the allelopathy of two different treatments,
Eucalyptus (Eucalyptus cinerea) and Lemon (Citrus limon). The two treatments will be tested on
radish seeds (Raphanus sativus) to investigate the effect of the treatments on the germination of the
radish seeds. Allelopathy is the beneficial or harmful effects that one plant has on another plant by
the release of chemicals. Allelopathy studies the interactions among plants, fungi, algae and bacteria
with the organisms living in a certain ecosystem, interactions that are mediated by the secondary
metabolites produced and exuded into the environment (Francisco A Macías, José MG Molinillo,
Rosa M Varela, Juan CG Galindo 2007). The plants use ... Show more content on Helpwriting.net ...
In the dishes, I dropped the appropriate treatment into the center, where the marks were made. Next,
I closed the petri dishes, taped them up, and let them sit at room temperature for a week. Then I
opened them up to take two measurements. The first measurement was the number of seeds
germinated. The second measurement was to measure the seedling lengths.
Results All five groups recorded the outcomes that they established. For our bench, we found that
nine raddish seeds in the control dish, zero raddish seeds in the eucalyptus dish, and four radish
seeds in the lemon dish germinated and sprouted. Our bench also found that the average seed length
for the control was thirty one millimeters, for the Eucalyptus was zero. and for the Lemon was eight
and a half. Below, is a chart and graph that shows the whole data as averages from all five benches.
Each bench did the exact same experiment so we knew nothing would be biased.
Amount of Radish Seeds Germinated
Treatment Average Number of Seeds Germinated per Dissh Percent Germination
Control 9.4 94%
Eucalyptus 0 0%
Lemon 2.8 28%
Chart: The above chart shows how many radish seeds were germinated and sprouted. The right
column shows the percentage of seeds that germinated for each treatment out of one

Allelopathy and the Alliaria Petiolata Essay
Introduction
The term 'allelopathy' was introduced in early 1937 by Molisch when he discovered that there
existed both detrimental and beneficial biological interactions among all plants and microorganism
(Rivzi 1). His discovery aided Rice in coming up with a more clear definition of allelopathy.
According to Rice, allelopathy is any effect (beneficial or harmful) by one plant or microorganism
on another via excretion of chemical compounds to the environment (Rivzi 1). Since then, many
researches have been carried out to determine the beneficial and detrimental impacts of allelopathy
on agricultural practices. For instance, Bellard, McCarthy and Meekins studied on genetic variation
as well as biogeography of Alliaria petiolata in North ... Show more content on Helpwriting.net ...
They also found out that the effects of Alliaria petiolata varied with plant species; some species such
as G. laciniatum was least sensitive to the allelopathic interference. In their study, Meiners and
Pisula also found out that invasive plant species conquer and advance successfully in introduced
areas because of allelopathy. According to them, invasive plants produce allelochemicals that inhibit
the growth of the indigenous plants (Meiners and Pisula 81).
Problem statement
As introduced above, it is evident that many researches have been carried on detrimental effects of
Alliaria petiolata. However, it is evident that little has been discussed on how this plant species
hampers with the growth and development of other plants in a given area. Many researchers have
not mentioned in their studies on how this plant species affect the carbon and nutrient cycling in a
given environment. They have also not conducted experiments to justify their claims. Unfortunately,
it is through such negligence in researches that Alliaria petiolata managed to conquer and spread
widely in North America. For effective management of any problem in agriculture, it is crucial for
its effects on other plants to be analyzed fully. Thus, it is crucial for the carbon and nutrient content
of a given environment to be analyzed in order to know and understand the effects of Alliaria

Kudzu Argumentative Essay
1876 was a year to remember in the American culture. During this year at the Centennial Exposition
in Philadelphia Pennsylvania, we as Americans were introduced to many wonders that we still use or
come in contact with today. For example the telephone or the type writer, though the make and uses
of these devices have changed, if it were not for the exposition who knows what we as Americans
would be utilizing today. But not all items introduced at the exposition continued to be beneficial to
the everyday American. Some items would later become more of a nuisance rather than a benefit to
the country for the decades to follow. What item might you ask this would be? That item would be
Kudzu. Kudzu is a fast growing vine from eastern Asia. This vine was introduced ... Show more
content on Helpwriting.net ...
Eventually this news spread and in the 1970's the government declared Kudzu a weed, or a wild
plant growing where it is not wanted and in competition with cultivated plants. (3) Then in 1998
Kudzu was declared a noxious weed or a plant considered harmful to both animals and the
environment. (4) Kudzu now infest 31 states. This vine now covers 7 million acres in the United
States. The cost of the damage caused by this plant has surpassed the 100 million dollar mark and
continues to grow. Because of this, Kudzu is now banned in four states. Getting rid of Kudzu is a
difficult task but not impossible. Over the years we have also discovered there are many alternatives
Kudzu can be used for. For instance the blossoms are used in teas, the leaves can be eaten similar to
turnip greens, food for livestock, and is even being used as an herbal supplement for recovering
alcoholics. While we search and find many other uses for Kudzu, the problem of its quick growth
and abundance in the US remains. Scientist continue to look for solutions to this problem. But, has
nature already provided the solution man needs? If so how can we take advantage of such a

A Experiment On Paramecium Experiment Essay
Paramecium Experiment Introduction The purpose of the paramecium experiment was to observe
competition or allelopathy between two different species of paramecium in the laboratory.
Allelopathy is a way organisms inhibit or affect other organisms when developing in nature. This
insures the survival of one organism against another organism. For instance in plants, some can
release a chemical that enters the environment and inhibits the growth and development of
surrounding plants. Another example in nature is plants developing defenses to prevent herbivores
from eating them. This kind of competition happens in nature when the need for resources is limited
and survival is necessary. Competition is displayed throughout nature all the time. A man named
Georgy Gause previously conducted this experiment between P. aurelia and P. caudatum. He
determined that different factors influence how the two species compete and coexist. Ever since then
not many scientist have attempted to experiment on paramecium. Only until recently have more
experiments been attempted. The issue with the experiment was that it was conducted in 1935 and
nowadays there are more advance ways to conduct and interpret the experiment and results. As
previously stated, knowledge on this particular subject has been limited. Ever since Gause's
experiment, not many other scientists have attempted it until recently. As a class, the experiment was
a way to observe competition and better interpret the results gathered

Petric Competition Experiment
Introduction Almost all living things deal with competition, including plants. In order to understand
competition, it is first necessary to understand niche. A niche is a species ecological role in a
community (Brooker et al. 2016). Competition occurs when there is an overlap of the niches this
causes the plants to compete for the limited amount of resources. Competition is an interaction
where both of the parties involved are negatively impacted. There are four main types of
competition. Intraspecific competition occurs between individuals within the same species. Another
type is interspecific competition, which occurs between individuals of separate species. The other
two types of competition depends on how the members are competing. One ... Show more content
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Our results support this hypothesis since when garlic was present in the petri dish there was no
growth, compared to the control where there was growth. This was because of the chemical that
garlic releases, allicin (Djurdjevic 2004). For the second experiment, we hypothesized that the garlic
bulb would have the greatest effect on lettuce seed growth. Our results supported this hypothesis
since there was no growth in the lettuce seeds when the bulb was present. This occurred because the
bulb releases allicin which prevents the uptake of organic substances in the seeds (Djurdjevic 2004).
Therefore, we reject the null hypothesis. The data suggests that our alternative hypotheses were
correct. During our experiment, there were a few possible sources of error. One is the presence of
mold growth in some of the petri dishes. This could have skewed some of the data. Another possible
source of error is that since different students measured each seedling sprouts, they could have
measured differently from the next person. This would cause some of the measurements to be either
too low or too high. The third possible source of error is that the parafilm did not completely seal the
petri dishes. This would have caused the petri dish to dry out and would inhibit growth for the
lettuce

Competition And Predation Play An Important Role
Coexistence has been happening among many species since the beginning of time throughout
nature. The way species exist is of great complexity as many factors such as: competition and
predation play an important role (Chase et al. 2002; Holt 1984; Paine 1966). Ecosystems,
communities and populations all face competition between their species. Studies are constantly
being done to show how different species survive together or die trying and what is it that they are
fighting to survive over. Different habitats, predator, prey, and so many other factors play a role in
the survival of species like protists. Many laboratory studies have been done on two protists,
Paramecium aurelia and Paramecium caudatum, to see different aspects of their ... Show more
The prey will go slam down on the ground in seconds and be devoured in minutes by the lion. The
lion is allelopathy at its best because there is competition over survival and territory with animals of
this nature. Territory can be a limited resource depending on the time of year and the environment as
a whole, trees and brush being chopped down pose a problem when it comes to sneaking up on prey.
Gause started experimenting on protists to observe their development and observe their survival
ability together (Gause). Paramecium can be found in many places: wet areas like lakes and rivers or
dry areas such as those of trees and soil. Gause set out to experiment with Paramecium aurelia and
Paramecium caudatum to determine if they fit the competitive exclusion theory that he came up with
(Gause 1935). The class was given both parameciums to experiment with for the validity of
coexistence. The competitive exclusion theory begs the question, can two species coexist together
over a resource or will one of them be driven to extinction? Gause may have been the leader to start
the protists experiment but he wasn't the only one to question competition. Gill had questioned
Gause's theory and decided to do his own research. Gill experimented on two species pure and
mixed cultures of Paramecium aurelia. After experimenting Gill discovered that Paramecium aurelia
did not match up to Gause's theory and did not compete over a limited resource instead

Agriculture-the Alleopathic Effect of Weeds on Crops
Practical Research & Report Assessment.
Allelopathy and interference and the effect they have on plant growth.
Allelopathy occurs in plants. Many plants produce chemicals that may be harmful or beneficial to
other plants. In some cases a species can produce chemicals that can prevent the growth or
germination of another species. An example of this is Australian native plants such as Casuarinas
and Eucalypts which produce allelochemicals that prevent competition of other plants. This is a
form of a defence mechanism in order to survive. A negative effect of Allelopathy includes
Patterson's Curse. Patterson's curse releases allelochemicals that inhibit the germination and growth
of other plants. When plants are competing they compete for ... Show more content on
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Patterson's Curse was the most dominant weed in the experiment. Out of the 50 seeds that were
watered by Patterson's Curse tea only 8 of the seeds reached germination. This is because of the
strong allelochemicals that are released by the weed that take over the plant.
A similar result was seen by Blue Weed which is a very close relative of Patterson's Curse. Blue
Weed sufficiently stunted germination of the seeds with only 17 out of 50 seeds reaching
germination. This is because of the strong allelochemicals released by the plant.
Saffron thistle also had a clear negative impact on the seeds with only 21 out of the 50 seeds
reaching germination. Saffron Thistle is a fierce competitor for most plants because of its hardiness
and tolerance of low rainfall allows it to out do the competition.
Broom and Sorrel both had a minimal impact on the seeds with 36 out of the 50 seeds reaching
germination for each. Broom and Sorrel are not very strong competitors.
The control was almost a 100% success with 49 of the seeds reaching germination.
The experiment carried out conformed with the scientific protocol. In this experiment independent
variables and variables as

To What Extent To Different Concentrations Of Eucalyptus
To what extent to different concentrations of Eucalyptus microcorys (E. microcorys) at 0g/mL,
0.25g/mL, 0.5g/mL, 0.75g/mL and 1g/mL have an allelopathic effect on the germination of
Raphanus sativus (R. sativus) seeds as measured by the number of seeds germinated within seven
days? Ecology has been the study of different interactions amongst organisms with the abiotic
environment (Pimm and Smith, 2007), examining how ecosystems have thrived upon these
relations. Ecosystems have depended on the continued availability of energy supplied ultimately by
plants through the process of photosynthesis. Plants have lived in association with each other from
having occupied the same niche in nature (Khan and Hussain, 1999). Numerous plants have ... Show
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Although not every plant has contained allelopathic tendencies, these toxins can be located
anywhere on plants inclusive of roots, stems, bark, leaves, flowers and bearing fruits (Ferguson,
Rathinasabapathi and Chase, 2016). Nevertheless, there have been variations in allelochemical
concentrations within different parts of plants. For instance, eucalyptus foliar litter leachates have
been assessed to have been more toxic than bark leachates (Ferguson, Rathinasabapathi and Chase,
2016). Because of its invasive nature, there have been various applications of allelopathy within
horticultural practices. Particularly in the agriculture industry, specific allelopathic plants have been
researched to become potential natural, biodegradable herbicides against weeds, cultivators in crops
and growth regulators in large–scale agroforestry manufacturing (Reza, 2016). A popular example of
this form of chemical warfare has been shown by the Black Walnut, a species native to eastern North
America. Conversely, in Australia, there have been numerous eucalyptus species have been
experimentally evaluated to have shown allelopathic behaviour towards other plant species,
ordinarily in volatilisation with shrouded vapourised volatile chemicals called terpenoids released
within remote outback bushlands (Külheim, Padovan, Hefer, Krause, Köllner, Myburg and Foley,
2015). Even from a discernible observation, it has been evident in urbanised cities or municipalities
that eucalyptus

Disadvantages Of Weed Infestation
Weed infestation has been known to cause substantial reductions in crop yields thereby obstructing
sustainable agriculture (Ayeni et al., 2013). Weed competition was identified by Mbanje et al. (2001)
as the most important factor for yield reduction in both commercial and communal farming in
Zimbabwe. Weeds threat had forced farmers to use synthetic herbicides which have detrimental
effects on the environment. Synthetic herbicides are also expensive and are not readily available for
communal farmers' use. Chemical and mechanical weed management reduce profitability in crop
production since these methods are expensive. Recent efforts are being intensified on finding
alternative strategies for weed management. The need for safe food production has developed
steadily over the years as a result of consciousness about food quality and environmental concerns
regarding agrochemicals used in agriculture. Such efforts include the use of allelochemicals which
are believed to be much safer than synthetic herbicides. Crops/plants release chemicals i.e
"allelochemicals" which could be utilized for ... Show more content on Helpwriting.net ...
Chemical and mechanical weed control methods are associated with many disadvantages. There is
need to improve the cultural methods of weed management such as the use of allelopathy. Sorghum
has allelopathic properties which reduce weed germination and growth but is not known whether
different varieties produce different levels of allelochemicals. Knowing sorghum varieties with best
allelepathic effects on the common weeds will help in reducing weed problems in Zimbabwe. Local
studies have not shown the extent to which sorghum allelopathy can suppress germination and
growth of Acanthospermum hispidum and Elusine Indica. The extent to which soil type affects
allelopathic weed control has not been shown by local

How Does Voc's Affect Plant Communication?
Human observers of nature are familiar with the communication among animal species. For
example, a bird's call may alert others to a predator, or a wolf's howl–bark may help coordinate a
hunt (Wolf Talk, 2015). Less obvious, however, is the wondrous ways in which other creatures–
fungi and plants– communicate and share resources. These interactions may be symbiotic and thus
mutually beneficial.
Plant communication can occur through the release and reception of airborne volatile organic
compounds (VOC's) (Ueda, Kikuta, Matsuda, 2012). These VOC's are released during
photosynthesis. The plant releases metabolites other than glucose, including what gives the plant
color, taste, and smell (Kegge, Wouter, Gankema, Paulien, Pierik, Ronald, 2013). The VOC's not
only determine the plant's smell, but also are used to attract pollinators and communicate with other
plants. This also allows enemies to locate the place of battle by "eavesdropping" on VOC's.
Different blends and types of VOC's emit different messages (Ueda et al., 2012). The most common
VOC's are terpenoids and green leaf volatiles (Kegge et al., 2013). VOC's are also used in
communication within one plant, for example to coordinate branches. In contrast, some VOC's,
rather than warning plants of danger and recommendations to adjusting their defense systems, can
function as herbicides and harm other plants (Arimura, Shiojiri, Karban, 2010).
Plants not only communicate through chemicals also can transfer carbon and

Spanish Moss Essay
Spanish moss, Tillandsia usneoides L, is not a moss, but a flowering and fruiting aerial epiphytic
bromeliad. It is one of nine Tillandsia species typically living in warm, humid climates on trees or
other supporting structures such as fences and power cables (Billings 1904; Garth 1964; Callaway,
et al. 2002). This epiphyte is distributed between 38°N and 38°S latitude, up to 3300 meters above
sea level (Garth,1964 and Gentry,1987), and is native to Mexico, Central America, South America
and the Caribbean. It grows from Texas to Virginia in the United States (Barve, 2015).
Tillansia usneoides does not require a specific host tree and so are considered generalists (Ackerman
et al. 1989, Tremblay et al. 1998, Benzing,1990). However they appear ... Show more content on
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2012 and Norquay, 2010). In contrast, seminole bats (Lasiurus seminolus) and evening bats
(Nycticeius humeralis) take advantage of the insulatory properties of the bromeliad in pine trees
(Hein, et al. 2008 and Jennings, 1958). Spanish moss maternity roosts are open and clear from
below, allowing for easy entry/exit by multiple family members, as well as providing protection
from storms, which can knock bat pups to the ground, endangering their survival. Bats are able to
drink water off the epiphyte leaves and eat insects which take refuge in the branches. Many,
especially juveniles, can become ensnared in epiphyte "festoons", the hanging stem's classical
descriptive term. The occurrence of bat and bird entrapment and mortality in areas heavily infested
with Tillandria is unknown, but most likely infrequent (Norquay, et al. 2010). Southern flying
squirrels (Glaucomys volans) are known to nest within Tillandria streamers, adding hair, wool,
feathers, lichens, pine straw and grass (Prange, 2006). The eastern rat snake (Pantherophis
alleghaniensis), gray rat snake (P. spiloides), and red corn snake (P. gutatta) have also been recorded
nesting and foraging within the tangles of Spanish moss, both in trees and on the ground. Likewise,
Cuban tree frogs and green anole lizards have been known to

What is Allelopathy?
Introduction Allelopathy originates from the Greek language; Allele means two sided harm, and
pathy means suffering (Willis, 2010). The release of chemicals by one plant that can affect the
growth of another plant is called allelopathy (Ferguson, 2003). The chemicals released from a plant
which possess allelopathic influences are termed allelochemicals or allelochemics (Johnson J,
2012). Different parts of a plant can secret allelochemicals. They can also be released naturally
(Cipollini, 2012). They can be found in leaves, pollens, roots, fruits, or stems (Martin, 2012).
According to Heisey (1996), species can be affected by these chemicals in many different ways. The
toxic chemicals may inhibit shoot or root growth, they may inhibit the uptake of food, or they may
disrupt a symbiotic relationship thereby destroying the plant's usable source of a nutrient.
Allelopathic plants may also have beneficial effects (Cipollini, 2012). They are used as a means of
survival in nature, and decrease the competition between plants nearby. According to James J
(2003), chemicals found to inhibit the growth of a species at a certain concentration may stimulate
the growth of the same species or another at a lower concentration. For example, many trees use
allelopathy to protect their space by using their roots to pull more water from the soil so other plants
cannot thrive (Willis, 2010). In other words, some use their allelochemicals to inhibit germination or
to prevent development

What Is Allelopathy?
A. The positive and deleterious effects of plant interactions is an area of important study considering
a large portion of the worlds dietary needs revolve around plants. As humans wage war for
resources, plants wage chemical warfare, silently, around us. In agriculture, allelopathy of plant
extracts has many applications, during crop rotation, mulching, and pest management.(1)
Allelopathy helps explain why invasive species are able to be so prolific and why native species are
not properly equipped to deal with it. Many invasive species were brought from Europe before plant
communities were well understood. B. A biennial, garlic mustard or Alliaria petiolata is an invasive
species introduced in the 1860s from Europe for medicinal uses. First

Bay Laurel Essay
My hypothesis was correct, the 100% Bay Laurel Solution worked most effectively as compared to
the other solution. My data supports my hypothesis by showing that the 100% Bay Laurel controlled
the dandelions within four days. The 75% Bay Laurel solution controlled the dandelions within six
days, the 50% Bay Laurel solution controlled the dandelion within seven days. The control group,
however, was not able to control the dandelion in the given time.
The most important part of the experiment was not whether the hypothesis was correct, but it was
what I gained from the project. As I progressed with my experiment, I learned many things. My
knowledge of the Bay Laurel, Laurus nobilis, plant expanded greatly. I learned that the Bay laurel
was a large shrub with green and glossy ... Show more content on Helpwriting.net ...
First, my experiment provides an organic, non–chemical weed killer, that people may use. Using an
organic weed killer does not pose a large threat as compared to a chemical weed killer. The chemical
weed killer would affect the soil, nutrients, and the water underground in a very harmful way. On the
other hand, the Bay Laurel weed killer does not pose such a large threat because of the fact that the
organic weed killer itself is a plant. There is also a price difference, chemical weed killer costs about
$15–30. In contrast, the Bay Laurel weed killer requires plain tap water and Bay Laurel leaves.
Another advantage of an organic weed killer is that it does not affect the human health as greatly as
the chemical weed killers. For example, if chemicals come in contact with the skin, it may cause
irritation and even a rash. However, Bay Laurel has a distinct, soothing fragrance. The only time to
be concerned is when the Bay Laurel has been eaten, due to the fact that it can destroy internal
organs. Even though it might take more time and effort than a chemical weed killer, it is worth it to
save our environment and the

The Experiment Of The First Experiment
Unlike the first experiment which lasted three seasons, this one lasted only one season, from May to
November 2013. Following a seed pre–germination period of 72 hours in the dark (25°C), all
treatments were planted in 2.5 L pots filled with a nitrogen free substrate of fine quartz sand. The
authors disposed the pots in rows with 15 cm inter–rows. They further fertigated the growing plants
every two hours with a complete nutrient solution, excluding nitrogen. Similarly to their first
experiment, the authors arranged this one in a slit–plot design with four replicated blocks. This time,
they used six treatments per block: 1) alive alfalfa and tall fescue; 2) dead alfalfa and tall fescue; 3)
alive white clover and perennial ryegrass; 4) dead white clover and perennial ryegrass; 5) pure tall
fescue and; 6) pure perennial ryegrass. These treatments were divided between two randomized
sub–blocks with or without a legume. For the dead legumes, the authors previously grew the plants
for three months, then cut them right below the taproot collar and further planted the grass species
according to the treatments. Four days after the transplant, treatments containing live legumes were
inoculated with rhizobia. To do so, the authors collected soil from the 0–20 cm soil horizon of
experiment 1. They took several samples, mixed them and dissolved a sub–sample of 10 grams into
1 L of deionized water. The authors then inoculated experiment 2 pots with 10 mL of this solution
and further

Essential Oils : Natural Products
Essential oils are natural products formed in aromatic plants which are characterized by unique
features of odor and flavor for their own benefits such as protection or attraction (7). The oils are
accumulated in cells, located in tiny secretory structures or in glandular hairs of the plant. The
interior of the stomatal cells is typically the location of where the essential oils are found.
While they are located within the plant, essential oils are continuously altering their chemical
composition to adapt its host plant so ensure its utmost health in its surrounding environment. The
actual area of the plant where the oils are sequestered varies depending on the type of plant.
Common areas and examples of where essential oils are derived from: leaves (eucalyptus, mint,
lemongrass), flowers (jasmine, carnation, rosemary, lavender), bark (cinnamon, canella), roots
(angelica, sassafras, valerian), seeds (nutmeg, dill, caraway), fruits (orange, lemon, juniper), grasses
(palmarosa), petals (rose), wood (cedar) rhizomes (ginger, calamus, orris) berries (juniper), resins
(frankincense) and wood (cedar, sandal, pine), and others (5).
Each essential oil has unique properties and functions in nature such as attracting pollinators and
dispersal agents, to serve as internal messengers for the plant host, releasing chemicals to aid in
allelopathy, to serve as defense compounds against insects and animals, and to protect the plant with
their antiviral, antibacterial and antifungal

Eucalyptus Globulus' Effect on the Germination of Radish...
The purpose of the project was to determine whether Eucalyptus globulus had an effect on the
germination of radish seeds. It was hypothesized that Eucalyptus globulus would have a negative
effect on the germination of the seeds and their growth.
Before a seed can germinate it must first shed the seed coat, a protective outer layer that protects the
seed from parasites, injury, and unfavorable temperatures. Inside the seed coat is the embryo which
contains the root and first leaves of the plant, called cotyledons. After the seed coat has been shed
the root emerges first so that it can absorb water and nutrients. After the roots have come out of the
embryo the cotyledons will follow. Some seeds need certain conditions to germinate and go ... Show
more content on Helpwriting.net ...
Allelopathic chemicals can also exist in soil, affecting the surround plants and those planted
afterwards. Studies have shown that Leucaena leucocephala, a tree promoted for water conservation
and revegetation, contains a toxic amino acid in its leaves and foliage that prevents the growth of
other trees but not its own seedlings. Research has also shown that this species reduces the yield of
wheat and increases the yield of rice. Other allelopathic plants include mango, box elder, broccoli,
and Eucalyptus. A study was conducted at Gomal University that tested the allelopathic effects of
Eucalyptus camaldulensis L. on the germination and seedling growth of wheat. The leaves of E.
camaldulensis trees were washed and dried and then filtered to create a one hundred percent solution
as well as ten percent, fifteen percent, and twenty percent. These solutions were tested on twelve
varieties of wheat. The results showed that there was a significant decrease in germination counts
with increasing levels of Eucalyptus aqueous extract concentration. All twelve varieties of wheat
were adversely affected by the twenty percent concentration of Eucalyptus extract. It was observed
that there was a direct relationship between the number of normal seedlings and the extract
concentration. The results suggested that the E. camaldulensis L. leaf aqueous extract could reduce
normal seedlings even in low concentrations.
Eucalyptus

Essay about Coral Reefs
Coral reefs have been undergoing global degradation due to increasing natural and anthropogenic
impacts for at least the last half–century. The intensity and frequency of stressors, including global
climate change, have rapidly increased in number over recent years (Hughes & Connell 1999;
Hoegh–Guldberg et al. 2007; Pandolfi et al. 2011). Frequent disturbances such as
hurricanes/cyclones, predation outbreaks, diseases and mass bleaching events eat–away at the
percent of living coral cover and without recovery, the available space is colonized by sponges, soft
corals, and macroalgae. These alternative organisms are often competitive dominants in less than
ideal conditions (Norström et al. 2009). The transition is termed a phase–shift from ... Show more
1993; Lirman 2001; Box & Mumby 2007), increased localized sedimentation (Nugues & Roberts
2003), interfering with the settlement of coral larvae through space preemption and/or biofilm
production (Birrell et al. 2005; Birrell et al. 2008; Box & Mumby 2007; Vermeij et al. 2009), and
allelopathy or chemically mediated competition (deNys et al. 1991, Morrow et al. 2011).
Macroalgae can cause physical stress (Quan–Young & Espinoza–Avalos 2006) decreased
photosynthetic abilities (Titlyanov et al. 2007), reduced fecundity (Foster et al. 2008), and harbor
potential coral pathogens (Nugues et al. 2004). The ability of macroalgae to competitively damage
stony corals also depends on the species of macroalgae (Maypa & Raymundo 2004; Birrell et al.
2008), and other compounding factors such as irradiance, sedimentation, dissolved nutrients, and
level of herbivory on the reef.
Over the past several decades the incidence of coral disease has increased, with striking correlation
to increasing macroalgal cover (Goreau et al. 1998; Harvell et al. 1999; Harvell 2004; Weil & Smith
2006). The enhanced need for disease research coupled with the massive advancements in molecular
techniques made the study of coral–associated microbes more efficient and less cost prohibitive.
Thus, we have recently recognized the significant role microorganisms play in the physiology of
both healthy and diseased corals. The term holobiont was coined to describe the dynamic
relationship

Preliminary Biology Yearly Notes
Biology Year 11 Yearly Notes Chapter One – A local ecosystem 1.1 Terrestrial and Aquatic
Environments –Ecosystem: any environment containing living organisms interacting with each other
and with the non–living parts of that environment. –Environment: the environment of an organism is
its surroundings, both living and non–living –Habitat: the habitat of an organism is the place where
it lives. Australian Environments * Terrestrial environments are environments on land. Land covers
about 35% of the Earth's surface. * Aquatic environments are water environments. Oceans cover
about 65% of the Earth's surface. * Terrestrial and aquatic environments have very different abiotic
characteristics. Abiotic Characteristics ... Show more content on Helpwriting.net ...
All living things ultimately depend on this process. The compounds plants make during
photosynthesis provide nutrients and energy to organisms that consume plants. Organisms that
consume the plant–eaters gain nutrients and energy from them, so both energy and materials are
passed from organism to organism. Plants capture light energy and transform it into chemical
energy. This chemical energy is transferred from plants to animals via the food chains. –Respiration:
the process by which cells obtain energy. In this process, organic molecules, particularly sugars, are
broken down to produce carbon dioxide and water, and energy is released. Without photosynthesis
there would not be energy or carbohydrates available for the growth and reproduction of (almost) all
organisms. In addition photosynthesis produces oxygen, which is essential for the release of energy
in cells by the process of respiration. Uses of Energy by Organisms Energy from respiration powers
all the processes of life. Some energy is released as heat. Other activities include: * Growth *
Muscle contraction and movement * Synthesis of complex chemicals * Repair of damaged cells *
Reproduction Aerobic Cellular Respiration –Aerobic: requiring the presence of oxygen. Respiration
involves a chain of biochemical reactions. It's a controlled process occurring as a sequence of
around 50 different reactions, each one catalysed by a different enzyme. Stages of

The Effect Of Surface Residues On Weeds

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