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8 Mechanism of Cry1Ac Resistance in Cabbage Loopers – A Resistance Mechanism Selected in Insect Populations in an Agricultural Environment

Soberon, M. CABI PDF

8

Mechanism of Cry1Ac Resistance in Cabbage Loopers –

A Resistance Mechanism Selected in Insect Populations in an

Agricultural Environment

Ping Wang*

Department of Entomology, Cornell University, New York State

Agricultural Experiment Station, Geneva, New York, USA

Summary

The development of resistance to Bacillus thuringiensis (Bt) in insect populations in agriculture not only depends on the level of resistance conferred by a selected resistance mechanism, but also on the fitness cost associated with the resistance mechanism under specific ecological and environmental conditions. Bt resistance in the cabbage looper (Trichoplusia ni), which was identified by Janmaat and Myers (2003), is a case of

Bt resistance evolved in an agricultural system, and is used in this chapter to review and discuss the mechanism of Cry1Ac resistance that is selected in an agricultural environment.

8.1 Introduction

Resistance of insects to pesticide sprays in agriculture has been observed for a century

(Melander, 1914). Under selection pressure by pesticide applications, thousands of cases of pesticide resistance in hundreds of arthropod species have been recorded (MotaSánchez et al., 2008). Since the first report of insect resistance to Bacillus thuringiensis (Bt) in 1985 (McGaughey, 1985), the potential

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Medium 9781780643373

6: Coppice Silviculture: From the Mesolithic to the 21st Century

Kirby, K.J. CABI PDF

6 

Coppice Silviculture: From the

Mesolithic to the 21st Century

Peter Buckley* and Jenny Mills

Peter Buckley Associates, Ashford, UK

6.1  Introduction

Coppice refers to the repeated cutting of stems regrowing from a stump or ‘stool’ at intervals, typically from 5 to 30 years (Plate 6). It is one of the oldest silvicultural systems known, with well-documented archaeological evidence dating from Mesolithic, Neolithic, Roman and

Anglo-Saxon times in Europe. Such management would have maintained regular openness in woods, together with its many associated species. Rotation lengths are, however, generally too short to allow much development of conditions for late-successional species dependent on old growth, except in old coppice stools, or as occasional mature trees left on boundaries and as standards.

In modern Europe, the landscape now consists mainly of high forest patches, set in open landscapes dominated by agriculture.

Coppices have either been abandoned or converted to high forests, thereby reducing the intensity and frequency of disturbances and thus discriminating against species of open woodlands. In Britain, for example, woodland census data indicate an 80% contraction in the area of coppice from the post-war period 1947–

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2 Accounting for the Impact of Local and Spill-in Public Research, Extension and Roads on US Regional Agricultural Productivity, 1980–2004

Fuglie, K.O., Ball, V.E., Wang, S.L. CABI PDF

2

Accounting for the Impact of Local and Spill-in Public Research, Extension and Roads on US Regional Agricultural

Productivity, 1980–2004

1

Sun Ling Wang,1 V. Eldon Ball,1 Lilyan E. Fulginiti2 and Alejandro Plastina3

Economic Research Service, US Department of Agriculture, Washington, DC;

2

University of Nebraska, Lincoln; 3International Cotton Advisory Committee,

Washington, DC

2.1

Introduction

The study of the contribution of research investment to farm production and agricultural productivity was pioneered by

Griliches (1958, 1964), Evenson (1967) and their associates. The benefit of public research in agricultural productivity growth has been documented in numerous studies since their seminal work. On the basis of literature surveys by Evenson (2001), Alston et al. (2000), Huffman and Evenson (2006), and Fuglie and Heisey (2007), the rate-ofreturn estimates for agricultural research are high. In general, the rates of return to federal-state investment in agricultural research are in the range of 20– 60% (Fuglie and Heisey, 2007).

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Medium 9781780642994

8 The Current Nutritional Status in China

Thompson, B., Amoroso, L. CABI PDF

8

The Current Nutritional Status in China

Chunming Chen*

International Life Science Institute Focal Point in China, Chinese

Center for Disease Control and Prevention, Beijing, China

Summary

Based on data collected in China by the Food and Nutrition Surveillance System in 1990–2010, the National

Survey on Fitness of Students in 1985, 2000 and 2005, and the 2002 National Nutrition And Health Survey, this chapter demonstrates the dramatic improvement in the nutrition of children under 5 and the growth of school-aged children and adolescents during the period of rapid economic growth in China. Now, there is no longer undernutrition in urban areas and the prevalence of stunting in the countryside has declined from 40.3% in 1990 to 12.6% in 2009. The median height of various age groups of school-aged children and adolescents in cities are close to the reference used by the World Health Organization (WHO). Overall, the study showed an evident reduction in undernutrition in line with the rapid economic development in

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Medium 9781780645322

20 Climate Change and Soil Carbon Impacts

Banwart, S.A., Noellemeyer, E., Milne, E. CABI PDF

20 

Climate Change and Soil

Carbon Impacts

Pete Smith*, Pia Gottschalk and Jo Smith

Abstract

Soils contain vast reserves (~1500 Pg) of carbon (C), about twice that found as carbon dioxide in the atmosphere. Historically, soils in managed ecosystems have lost a portion of this C (40–90 Pg) through land-use change, some of which has remained in the atmosphere. In terms of climate change, most projections suggest soil C changes driven by future climate change will range from small losses to moderate gains, but these global trends show considerable regional variation. The response of soil

C in future will be determined by a delicate balance between the impacts of increased temperature and decreased soil moisture on decomposition rates, and the balance between changes in C losses from decomposition and C gains through increased productivity. In terms of using soils to mitigate climate change, soil C sequestration globally has a large, cost-competitive mitigation potential. Nevertheless, limitations of soil C sequestration include time limitation, non-permanence, displacement and difficulties in verification. Despite these limitations, soil C sequestration can be useful to meet short- to medium-term targets, and confers a number of co-benefits on soils, making it a viable option for reducing the short-term atmospheric CO2 concentration, thus buying time to develop longer-term emission reduction solutions across all sectors of the economy.

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