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7: Mites and Plant Damage

Vacante, V. CABI PDF

7   Mites and Plant Damage

Pest mites sensu stricto belong to the Tetranychoidea and

Eriophyoidea, both of which have mouthparts that are able to pierce plant tissues and suck out their contents. Other mite groups (Acaridae, Erythraeidae, Penthaleidae, etc.) have dif­ ferent mouthparts that are not strictly adapted to phytophagy, but are nevertheless also able to cause severe damage. The feeding mechanism, together with the plant response, determine the damage typology. Plant damage by mite pests has been

­extensively investigated in the Tetranychoidea and Eriophyoidea, but less so in the Tarsonemidae and other minor phytophagous groups. Sometimes, the symptoms can be easily taken for boron deficiency, or they may be confused with virus symptoms or even with herbicide action, such as on the new leaves of papaya infested by the broad mite, Polyphagotarsonemus latus (Banks).

The main part of this chapter is devoted to an account of the damage to plants that is caused by the main phytophagous groups of mites (Tetranychoidea, Eriophyoidea) and others

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Medium 9780253012821

15 Visible Time

John Sallis Indiana University Press ePub

 

Boston

October

Not many leaves have yet fallen. Most are still green, even if beginning to show fringes of orange and yellow. Yet there are already a few trees that have donned their fall colors, displaying them brilliantly on days that are bright and clear, attesting visibly to the arrival of the season. Though the sun now stays a bit lower in the sky and the character of the light is noticeably different from that of summer, there is still, on bright, clear days, more than ample sunlight to let the blaze of color appear in all its radiance. Though the light itself seems more transparent than ever, the shining of color that its presence releases is unmatched by any other that nature has to offer. With the arrival of these bright, clear autumn days, it is as if the glorious yellows, oranges, and reds had been held in store throughout the summer, as if they had been carefully prepared by nature to announce the advent and then the progress of the new season. Within a couple of weeks the color will have reached its high point, and only the evergreens will have escaped nature’s brush entirely. Yet by then the leaves will also have begun to fall.

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Medium 9781780643137

4: Trade in Meat

Phillips, C.J.C. CABI PDF

Trade in Meat

4

4.1  Introduction

Humans are not anatomically or physiologically designed to eat raw meat. The absence of elongated canine teeth makes tearing through raw meat difficult and the relatively high pH in our stomachs renders us susceptible to food poisoning if the flesh is at all contaminated. For our ancestors the infrequency of successful hunts would have made contamination of stored meat likely. However, their ability to master fire provided a method of processing meat to make it more easily consumed and less likely to be contaminated. Hence for as long as prehistoric records are available, meat consumption has been a part of the human diet. Our ancestors’ advanced ability to communicate facilitated complex hunting methods, luring animals into traps for example. Cave paintings suggest that there were ritual gatherings before the hunt, perhaps even with music and hallucinogenic drugs, which bonded the males together to improve their performance in the hunt.

Hunting for meat provided an alternative to the long process of gathering nutrients from plant life, which varied with climate and season and often required a nomadic lifestyle to follow the geographic availability of suitable plants. The nutrient demands for hunting, gathering and nomadism were considerable, and meat was able to provide the highly digestible food needed. Nevertheless, the risks involved and uncertainty in finding food meant that life was short, typically 25–40 years. With the coming of agriculture, and the development of improved plants, principally cereals, with higher seed yields, a settled way of life became possible and it was no longer necessary to hunt animals for meat. However, in colder parts of the world, particularly the northern parts of the northern hemisphere, meat consumption remained necessary because it could provide the nutrients needed, and in these regions crop growth was limited. Over the last 1000 years people from these regions came to colonize most of the rest of the world and the colonizers took their meat-eating habits with them. For example, the British colonies covered one-third of the world at the beginning of the 20th century,

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Medium 9781780645599

15: Oregano

Ambrose, D.C.P. CABI PDF

15 

1

Oregano

K. Hüsnü Can Bas¸er1,2* and Ne¸set Arslan3

Anadolu University, Eskis¸ehir, Turkey; 2Near East University, Nicosia,

N. Cyprus; 3Ankara University, Ankara, Turkey

15.1  Botany

15.1.1  Introduction

The family Lamiaceae is composed of annual or perennial plants that are herbs or shrubs and are distributed mainly in the northern hemisphere and especially in the

Mediterranean region. Their stems are generally square in cross section. The botanical description is as follows: Leaves simple or lobed, opposite, each pair at right angles to the previous one (decussate). Flowers bisexual and zygomorphic, emerging from the bottom of bracts, in dense clusters and verticillastrate. Bracts similar to leaves. Calyx 5 toothed, campanulate or tubular. Corolla tubular at base, bilabiate above. Upper lip 2, lower lip 3 toothed. Stamen 4, 2 fertile and

2 sterile; 2 with long and 2 with short filaments. Ovary superior, 2-celled and each cell 2-ovuled, style subterminal or ovary

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Medium 9780253356758

3 Relationships and Relatives: The Lobe-Fin Family

Jennifer A. Clack Indiana University Press ePub

3.1. Cladogram of lobe-fins from Cloutier and Ahlberg (1997).

Introducing the Lobe-Fins

This chapter introduces the tetrapods’ closest relatives, explains how tetrapods fit into the scheme of relationships with other lobe-fins, and explores how ideas about the ancestry of tetrapods have evolved with changing perspectives.

There are a few characteristics of lobe-fins that distinguish them as a group, but the most conspicuous is the eponymous lobed fin, described more fully in Chapters 1 and 2, in which the paired fins are anchored to the respective limb girdle by a single bone. The structure appears to be a true shared, derived character of the group. Another shared feature is the possession of two dorsal fins, instead of the single one found in early ray-fins, and a third is the occurrence in the tail of a second series of fin rays growing above the body portion. This has enabled lobe-fins to evolve symmetrical tails without too much modification of the existing pattern, and they have done so in a number of separate lineages. The latter two features may after all be primitive for gnathostomes, but this is not clear. In addition, most early members of the lobe-finned group show an intracranial joint or hinge line. A hinge linked the front and back parts of the skull roof just behind the eyes, reflected in a matching hinge across the underlying braincase (see Chapter 2). The hinge line occurs at the point where the otoccipital portion of the braincase meets the ethmosphenoid dorsally, and the ventral otic fissure separates them ventrally (see Figs. 2.1, 2.3, 2.11, 2.13), an important landmark in building the vertebrate skull. The hinge itself is not seen in ray-finned fishes, and it is also lost from several of the lobe-finned groups independently, including tetrapods.

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Medium 9780253009821

8. The Late Miocene

Főzy, István ePub

The last 6 million years of the Miocene correspond with the Pannonian and Pontian ages across the area of the regressing Central Paratethys seaway. The likely already brackish Sarmatian Sea became completely separated from neighboring basins, and by the beginning of the Late Miocene a deep lake evolved in the area of the Carpathian Basin. Mountains began to stand out as islands and an endemic mollusk fauna evolved in the lake, making the correlation of these sedimentary sequences with those in distant areas difficult. This correlation is easier using fossil vertebrates from the coast of the lake or marshes, including the three-toed fossil horse, Hipparion. Huge amounts of debris from the rising mountains rapidly filled up the lake, which eventually became a shallow freshwater basin by the beginning of the Pliocene and then dried out entirely.

Some attempts to reconstruct the evolution and alteration of Lake Pannon by combining results from different stratigraphic methods (dinoflagellate, mollusk, mammal, and magneto-stratigraphy) and radiometric age determinations have proved successful in recent years. For example, it has been shown that the water level in the lake was quite low about 12 million years ago when the basin formed, and then later it rose slowly and the lake became deeper and deeper. The lake reached its largest extent about 9.5 million years ago, and from then on it tapered off due to the progression of rivers and increase in delta areas. The bulk of the debris arrived from the north, so the coastline of Lake Pannon advanced southward. By the start of the Pliocene, most of the lake had disappeared, and river plains took its place.

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Medium 9781780643236

2 Potential Use of Essential Oils, Plant Fats and Plant Extracts as Botanical Fungicides

Ganesan, S. CABI PDF

2

Potential Use of Essential Oils,

Plant Fats and Plant Extracts as

Botanical Fungicides

Pramila Tripathi1 and A.K. Shukla2

1Department

of Botany, DAV College, Kanpur, India; 2Department of Botany, Indira

Gandhi National Tribal University, Amarkantak, India

2.1 Introduction

Plant diseases are caused by a diverse group of microbes including fungi, bacteria, viruses, viroids and nematodes. Plant pathogens create challenging problems in the cultivation of crops and pose real economic threats to farming systems because they are constantly mutating, resulting in new strains and new challenges to growers. There is a multiplicity of methods currently being employed for the management of plant pathogens such as physical, chemical, biological and cultural methods. One effective method to control plant pathogens has been the application of artificial pesticides (Kiran et al.,

2006) as they are toxic or inhibitory to the pathogens, dependable in terms of activity and also justifiable in terms of benefits compared to cost. Application of artificial pesticides has been successful overall in combatting phytopathogens. It has contributed to increased crop yields and enhanced stability of crop production and has maintained the market quality of the produce (Froyd, 1997). However, indiscriminate utilization of artificial pesticides for control of plant pathogens has caused an imbalance in environmental equilibrium and potential

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Medium 9781845939076

22 Lantana Mulching for Soil Fertility Improvement, Soil and Water Conservation and Crop Yield Enhancement in Rainfed Rice in the Kumaun Hills

Edited by J.R, Bhatt J.S. Singh, S.P. Singh, R.S. Tripath and R.K. Kohli CAB International PDF

22

Lantana Mulching for Soil

Fertility Improvement, Soil and

Water Conservation and Crop

Yield Enhancement in Rainfed

Rice in the Kumaun Hills

P. Kumar, M. Pant and G.C.S. Negi

G.B. Pant Institute of Himalayan Environment and

Development, Kosi-Katarmal, Almora, India

Introduction

Rice is the predominant staple food crop of nearly half of the world’s population, its cultivation covering 147 million ha in 2002

(IRRI, 2003). Worldwide, the area under rice cultivation is increasing rapidly due to everincreasing human demand. In intensively cultivated rice fields the capacity of soil to supply plant-available nitrogen (N) may decline unless soils are managed properly

(Kundu and Ladha, 1995). In order to enhance and/or maintain crop productivity rice cultivators have become increasingly dependent on chemical N fertilizers.

It has been reported that optimization of carbon (C) and N cycling through soil organic matter enhancement can improve soil fertility and crop yield while reducing negative environmental impacts (Blevins and Frye, 1993; Drinkwater et al., 1998;

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Medium 9781780645681

12 Conservation Agriculture in South Africa: Lessons from Case Studies

Kassam, A.H. CABI PDF

12 

Conservation Agriculture in South

Africa: Lessons from Case Studies

Hendrik J. Smith,1* Erna Kruger,2 Jaap Knot3 and James N.

Blignaut4

Grain SA, Pretoria, South Africa; 2Mahlathini Organics, Pietermaritzburg,

South Africa; 3KEL Growing Nations Trust, Ladybrand, South Africa;

4

University of Pretoria, South Africa

1

12.1  Introduction

Mainstreaming sustainable agriculture systems in South Africa has become imperative. Severe environmental degradation, low farm profitability and poverty associated with current conventional production systems have brought the agricultural sector to a crossroads. If farmers in South Africa are offered a better chance to survive on the farm and if sustainable and economically viable agriculture is to be achieved, then the paradigms of agricultural production and management must be changed.

Conservation Agriculture (CA) is an approach to managing agroecosystems for improved and sustained productivity, increased profits and food security while preserving and enhancing the resource base and the environment. CA is characterized by three linked principles (FAO, 2001; Lal, 2010), namely: (i) continuous no or minimum mechanical soil disturbance; (ii) permanent organic soil cover; and (iii) diversification of crop species grown in sequences and/or associations, including the use of cover crops.

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Medium 9780253021021

8 Iberian Sauropod Tracks through Time: Variations in Sauropod Manus and Pes Morphologies

Peter L Falkingham Indiana University Press ePub

8.1. Geographical and geological setting of the main sauropod tracksites of the Iberian Peninsula located in four broad areas: Lusitanian Basin, Cantabrian Range, Iberian Range, and the Pyrenees.

Iberian Sauropod Tracks through Time: Variations in Sauropod Manus and Pes Track Morphologies

8

Diego Castanera, Vanda F. Santos, Laura Piñuela, Carlos Pascual, Bernat Vila, José I. Canudo, and José Joaquin Moratalla

THE IBERIAN SAUROPOD TRACK RECORD HAS YIELDED more than 100 sauropod tracksites ranging in age from the Middle Jurassic (Bathonian) to the Late Cretaceous (Maastrichtian). During this wide range of time, four different types of manus prints can be differentiated, changing in morphology from (1) speech-bubble–shaped with a prominent claw mark in digit I (Middle Jurassic), (2) kidney-shaped with a claw mark in digit I or (3) without a claw mark in digit I (Late Jurassic and Early Cretaceous), to (4) horseshoe-shaped (Cretaceous). Pes prints are slightly more conservative in morphology through the Mesozoic and are generally subtriangular. They can mainly be differentiated on the basis of the number and orientation of the claw marks, although the presence of a lateral notch behind digit V and the heel can be useful as well. There seems to be a lateralization of the claw marks after the Middle Jurassic, where the pes have four claw marks, two of them oriented anteriorly and two laterally. Subsequently, pes prints have three (Late Jurassic–Early Cretaceous) or four (Late Cretaceous) claw marks oriented anterolaterally and decreasing in size. The variation in the manus and pes morphology in the Iberian sauropod tracks is a reflection of the changes in the sauropod faunas over time. The different types of manus prints suggest that the forelimbs should play a major role in sauropod ichnotaxonomy.

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Medium 9788131803660

Ch_5b

Dipak Chandra Ghosh, Nripesh Chandra Ghosh, and Prabir Kumar Haldar Laxmi Publications PDF

Quantum Mechanics

& 393

According to kinetic theory of gases, the average kinetic energy of the material particle,

1 2

3 mL = k T

2

2 h l= k : Boltzmann constant

3m kT

E= then

n Group velocity : vg =

dw dE

= dK dp

where E = hw and p = hK

w

K n Heisenberg�s Uncertainty Principle :

· The product of uncertainties in determining the position (Dx) and momentum (Dp) of a particle at the same instant is Dx Dp ³ h

· The uncertainty in determining energy (DE) and time (Dt) is given by DEDt ³ h

· The uncertainty in determining angular momentum (DJ) and angle (Dq) is given by

DJDq ³ h

n Phase velocity : vp =

Applications :

1. Non-existence of free electron in an atomic nucleus

2. Radius of the Bohr�s first orbit. o dinger Wave Equation : n Schr && odinger equation

1. Time independent Schr &&

2 m

D2y + 2 E - V y = 0 h

a

f

2. Time dependent Schr && odinger equation h 2

¶y

Ñ + V y = ih

¶t

2m

F

H

I

K

Ñ2 º

where

¶2

¶2

¶2

+ 2 + 2

2

¶x

¶y

¶z

n Expectation values :

· Expectation value of any observable A is defined by

$ y dx dy dz

= y * A

z

· Expectation value of momentum is

=

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Medium 9781780642895

11 Enhancing Climate Resilience of Cropping Systems

Fuhrer, J.; Gregory, P.J., Editors CAB International PDF

11

Enhancing Climate Resilience of

Cropping Systems

Heidi Webber,1 Helena Kahiluoto,2 Reimund

Rötter2 and Frank Ewert1

1University of Bonn, Institute of Crop Science and Resource

Conservation (INRES), Crop Science Group, Bonn, Germany;

2MTT Agrifood Research Finland, Plant Production Research,

Mikkeli, Finland

11.1 Introduction

How cropping systems will be impacted by the combination of rising temperatures, changing rainfall, more frequent extreme events and elevated CO2 is highly uncertain

(Tubiello et al., 2007; Osborne et al., 2013).

The attribution of changes in crop productivity to climate change is difficult due to concurrent developments in technology and management (Howden et al.,

2007; IPCC, 2010) which occur in response to many sociocultural, environmental and market factors (Smit and Skinner, 2002;

Mertz et al., 2009). However, growing evidence suggests that at a regional scale, crop phenology (e.g. Siebert and Ewert,

2012) and yields (e.g. Lobell et al., 2011) have already been impacted by increasing temperatures and days with extreme high temperatures (e.g. Reidsma et al., 2009;

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Medium 9781603448147

6. August—Bats in Carlsbad Caverns

Daniel S. Licht Texas A&M University Press ePub

6. August

Bats in Carlsbad Caverns

The sweltering desert landscape of the American Southwest may not seem like an ideal wildlife-watching destination in August. But within the caves at Carlsbad Caverns National Park in New Mexico the temperatures can run 20–40 degrees cooler than the outside desert. That cool subterranean climate is ideal for the hundreds of thousands of Brazilian (a.k.a. Mexican) free-tailed bats that roost in the caves during the day. Come evening the bats awake and leave the cave in a mass exodus as they venture out into the desert to feed. Watching swarm after swarm of bats corkscrew their way up into the fading twilight and then depart toward the distant horizon is one of nature’s great wildlife-viewing spectacles.

What’s Remarkable about Brazilian Free-Tailed Bats?

Every summer evening since time immemorial a half-million or so Brazilian free-tailed bats exit Carlsbad Caverns to head out into the surrounding desert to feed. Upon leaving the cave the “clouds” of bats—yes, that is one of the terms for a group of bats—corkscrew upward into the evening sky in a counterclockwise pattern. Why counterclockwise? Some have speculated that this behavior is due to the Coriolis effect, the same earthly phenomenon that causes the water in your bathtub to drain in a counterclockwise pattern (assuming you live in the Northern Hemisphere). Although the Coriolis effect is extremely weak, a bat trying to gain altitude needs all the assistance it can get, so the ascending bats may use it to more efficiently ascend. This counterclockwise pattern is so ingrained in bats they even use it in confined spaces such as inside houses. When the Carlsbad Caverns bats return to the cave at the end of the night they don’t need this earthly assistance to descend so they simply dive in a straight line into the cave entrance.

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Medium 9781780647845

13 Traditional/Commercial Uses and Future Dynamics

Khan, M.M. CABI PDF

13 

Traditional/Commercial Uses and Future Dynamics

M. Asif Hanif1*, Smitha Padmanabhan2, Mostafa Waly2 and Ahmed Al-Maskari3

1

Department of Chemistry, University of Agriculture, Faisalabad, Pakistan;

2

Department of Food Science and Nutrition, College of Agricultural and

Marine Sciences, Sultan Qaboos University, Al Khod, Oman; 3Department of

Crop Sciences, College of Agricultural and Marine Sciences,

Sultan Qaboos University, Al Khod, Oman

Introduction

Citrus aurantifolia (lime) belongs to the Rutaceae family (orange family) and is a genus of flowering plants. This tree is extensively cultivated in subtropical and tropical areas because of its edible fruits (FAO, 2009). The tree rarely reaches more than 5 m in height and 7.5 m in width; if not pruned it becomes shrub-like. Citrus is probably the most extensively planted fruit for direct human use in the world (Bakare et al., 2012).

The lime fruit and its juice are key ingredients in many drinks, confections, pickles and sauces.

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Medium 9781610910484

CHAPTER 1 - Climate Change and Transboundary Waters

Peter H. Gleick Island Press ePub

Heather Cooley, Juliet Christian-Smith, Peter H. Gleick, Lucy Allen, and Michael J. Cohen

Freshwater is a fundamental resource, integral to all ecological and societal activities, including food and energy production, transportation, waste disposal, industrial development, habitat for fish species, and human health. Yet freshwater resources are unevenly and irregularly distributed, with some regions of the world extremely short of water. Political borders and boundaries rarely coincide with borders of watersheds, ensuring that politics inevitably intrude on water policy. Indeed, over 260 river basins are shared by two or more nations. Just as oil creates disputes between states, water also plays a role in international conflicts. Inequities in the distribution, use, and consequences of water management have been a source of tension and dispute. In addition, as previous volumes of The Worlds Water have explored (see, for example, Gleick 1998), water resources have been used to achieve military and political goals, and water systems and infrastructure, such as dams and supply canals, have long been military targets.

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