Plant Biotechnology and Genetics

Principles, Techniques, and Applications

C. Neal Stewart, C. Neal Stewart

• Éditeur: Wiley
• Année: 2016
• ISBN:
  9781118819883
• Édition: 2
• Sujet: Biological Sciences
• Sous-sujet: Biotechnology

Focused on basics and processes, this textbook teaches plant biology and agriculture applications with summary and discussion questions in each chapter.

• Updates each chapter to reflect advances / changes since the first edition, for example: new biotechnology tools and advances, genomics and systems biology, intellectual property issues on DNA and patents, discussion of synthetic biology tools
• Features autobiographical essays from eminent scientists, providing insight into plant biotechnology and careers
• Has a companion website with color images from the book and PowerPoint slides
• Links with author's own website that contains teaching slides and graphics for professors and students: http://bit.ly/2CI3mjp

CHAPTER 1
The Impact of Biotechnology on Plant Agriculture

GRAHAM BROOKES

PG Economics Ltd, Frampton, Dorchester, UK

1.0. CHAPTER SUMMARY AND OBJECTIVES

1.0.1. Summary

Since the first stably transgenic plant produced in the early 1980s and the first commercialized transgenic plant in 1994, biotechnology has revolutionized plant agriculture. In the United States, between 80 and 90% of the maize (corn), soybean, cotton, and canola crops are transgenic for insect resistance, herbicide resistance, or both. Biotechnology has been the most rapidly adopted technology in the history of agriculture and continues to expand in much of the developed and developing world.

1.0.2. Discussion Questions

1. What biotechnology crops are grown and where?
2. Why do farmers use biotech crops?
3. How has the adoption of plant biotechnology impacted the environment?

1.1. INTRODUCTION

The technology of genetic modification (GM, also stands for “genetically modified”), which consists of genetic engineering and also known as genetic transformation, has now been utilized globally on a widespread commercial basis for 18 years; and by 2012, 17.3 million farmers in 28 countries had planted 160 million hectares of crops using this technology. These milestones provide an opportunity to critically assess the impact of this technology on global agriculture. This chapter therefore examines specific global socioeconomic impacts on farm income and environmental impacts with respect to pesticide usage and greenhouse gas (GHG) emissions of the technology. Further details can be found in Brookes and Barfoot (2014a, b).

1.2. CULTIVATION OF BIOTECHNOLOGY (GM) CROPS

Although the first commercial GM crops were planted in 1994 (tomatoes), 1996 was the first year in which a significant area of crops containing GM traits were planted (1.66 million hectares). Since then, there has been a dramatic increase in plantings, and by 2012 the global planted area reached over 160.4 million hectares.

Almost all of the global GM crop area derives from soybean, maize (corn), cotton, and canola (Fig. 1.1). In 2012, GM soybean accounted for the largest share (49%) of total GM crop cultivation, followed by maize (32%), cotton (14%), and canola (5%). In terms of the share of total global plantings to these four crops accounted for by GM crops, GM traits accounted for a majority of soybean grown (73%) in 2012 (i.e., non-GM soybean accounted for 27% of global soybean acreage in 2012). For the other three main crops, the GM shares in 2012 of total crop production were 29% for maize, 59% for cotton, and 26% for canola (i.e., the majority of global plantings of maize and canola continued to be non-GM in 2012). The trend in plantings of GM crops (by crop) from 1996 to 2012 is shown in Figure 1.2. In terms of the type of biotechnology trait planted, Figure 1.3 shows that GM herbicide-tolerant soybeans dominate, accounting for 38% of the total, followed by insect-resistant (largely Bt) maize, herbicide-tolerant maize, and insect-resistant cotton with respective shares of 26, 19, and 11%. It is worth noting that the total number of plantings by trait produces a higher global planted area (209.2 million hectares) than the global area by crop (160.4 million hectares) because of the planting of some crops containing the stacked traits of herbicide tolerance and insect resistance (e.g., a single plant with two biotech traits).

Figure 1.1. Global GM crop plantings in 2012 by crop (base area: 160.4 million hectare).

(Sources: ISAAA, Canola Council of Canada, CropLife Canada, USDA, CSIRO, ArgenBio.)

Figure 1.2. Global GM crop plantings by crop 1996–2012.

(Sources: ISAAA, Canola Council of Canada, CropLife Canada, USDA, CSIRO, ArgenBio.)

Figure 1.3. Global GM crop plantings by main trait and crop: 2012.

(Sources: Various, including ISAAA, Canola Council of Canada, CropLife Canada, USDA, CSIRO, ArgenBio.)

In total, GM herbicide-tolerant (GM HT) crops account for 63%, and GM insect-resistant (GM IR) crops account for 37% of global plantings. Finally, looking at where biotech crops have been grown, the United States had the largest share of global GM crop plantings in 2012 (40%: 64.1 million hectares), followed by Brazil (37.2 million hectares: 23% of the global total) and Argentina (14%: 23.1 million hectares). The other main countries planting GM crops in 2012 were India, Canada, and China (Fig. 1.4). In 2012, there were also additional GM crop plantings of papaya (395 hectares), squash (2000 hectares), alfalfa (425,000 hectares), and sugar beet (490,000 hect...