Crop Ferality and Volunteerism.
In May 2004, the workshop "Crop Ferality and Volunteerism: A Threat to Food Security in the Transgenic Era?" sponsored by the Organization for Economic Cooperation and Development (OECD) was held at Bellagio, Italy. It was motivated by the concerns of some societal groups regarding the possible environmental consequences associated with increasing cultivation of transgenic plants. The workshop provided the impetus for this book which is meant to address the subject of feral plants (crop plants that have become fully or partially dedomesticated) and the processes underlying ferality, as well as volunteer plants (plants germinating in seasons subsequent to their harvest) because of their potential role in ferality. Upon reading the book, one quickly realizes the many difficulties that persist in ascertaining and thoroughly characterizing ferality and its effects; nonetheless, the approach used in this book focuses on weeds closely related to crops, which often represent not only the predominant weeds and the more difficult to manage but also those most pertinent to potential interactions among related wild, weedy, and cultivated plants.
There has been a tremendous amount of information published about weeds, their identification, biology, impact, and management. However, this book devotes more attention to the evolutionary, biological, and cultural processes underlying the origin of weeds with special emphasis on domestication and dedomestication. It also serves to further our understanding of the intricate interactions within the wild-weed-crop complex on a crop-by-crop basis for a large number of crops cultivated worldwide. Ultimately, this knowledge should lead to a greater capacity to predict the impact of plants with novel traits (transgenic or not) on agriculture and the environment and also enable better informed genetic engineering, breeding, and cultural decisions.
While reading this book, one is quickly made to realize that the evolution and biology of weeds are not only extremely complex but also remain very difficult to fully elucidate. It becomes evident that the potential impact of feral plants and volunteers on both agriculture and the environment will vary enormously depending on the biological traits underlying domestication and dedomestication (and the characteristics of the genes responsible); the occurrence and relationship of neighboring wild plants, weeds, and crops (as well as their capacity and potential to intercross); and the cultural practices found around the world as well as the current and historical movement of plants among geographical locations. One further recognizes that each wild-weed-crop complex needs to be examined on a case-by-case basis, thus justifying the division of the book into chapters addressing specific crops. Each complex has its own distribution of relatives, parameters of interaction, economic repercussions, and management options as well as implications resulting from transgenic plant production (depending on the impact of the transgenic traits on fitness). Having these complexes detailed under a single cover by leading authorities in the field enables the reader to conveniently consider and compare the different systems.
The book is quite comprehensive and concentrates primarily on field crops via 24 chapters having formats ranging from research articles to reviews with black and white illustrations and photos. It begins with an introduction written by Gressel, the editor, identifying some of the challenges surrounding the definition and characterization of ferality. In Chapter 2, Warwick and Stewart further review the differences between domesticated crops, agricultural weeds, and feral crop plants and address in detail the domestication-dedomestication process. In Chapter 3, Ammann et al. bring a historical perspective to the ecology and detection of plant ferality and highlight contributions from historical and archaeobotanical research. The next 18 chapters deal with specific crops: beets in Chapter 4 by Sukopp et al.; oilseed rape in Chapter 5 by Hall et al.; foxtail millet in Chapter 6 by Darmency; urban ornamentals in Chapter 7 by Kowarik; sorghum in Chapter 8 by Ejeta and Grenier; soybean in Chapter 9 by Lu; maize and soybean in Chapter 10 by Owen; wheat in Chapter 11 by Ayal and Levy; rye in Chapter 12 by Burger and Ellstrand; radishes in Chapter 13 by Snow and Campbell; sunflower and other Helianthus species in Chapter 14 by Berville et al.; oat, olive, Vigna group, ryegrass species, safflower, and sugarcane in Chapter 15 by Berville et al. Each chapter is interesting in its own right and relates the evolution, complexities, and particularities of the wild-weed-crop complexes for each of these crops. The next five chapters: Chapter 16 by Vaughan et al.; Chapter 17 by Valverde; Chapter 18 by Marambe; Chapter 19 by Lentini and Espinoza; and Chapter 20 by Gealy, deal with rice and the important impact of weedy rice on its cultivation in different parts of the world. These chapters also bring to the forefront the role of crop-weed movement around the world as well as the effects of cultural practices and geographical locations. In Chapter 21, Vidotto and Ferrero discuss modeling of weedy rice infestation dynamics and underline both the benefits and challenges associated with modeling. Chapter 22 by Gressel and Al-Ahmad addresses the molecular containment and mitigation of genes within crops. Although the authors evidently favor their own approach, it is obvious that no approach provides a foolproof system for all crops yet and that this field of research holds as much potential as it does challenges. In Chapter 23, Raybould deals with the concept of risk assessment and its application to the case of transgenic volunteer weeds. In Chapter 24, Roush briefly outlines the importance of data for regulatory purposes. Lastly, the book ends with a short epilogue written by Balazs putting the contents of the book within a wider historical and cultural perspective.
Although this book was admittedly motivated by concerns raised by the increased cultivation of transgenic plants, the actual impact of transgenic plants on wild-weed-crop complexes is only addressed in depth in a few chapters. This is not unexpected given that there is not widespread cultivation of transgenic plants for many crops including major crops such as wheat and rice, and that only relatively few transgenic traits (e.g., herbicide or insect resistance) are available for thorough analysis. Nonetheless, the potential impact of transgenic plants is consistently addressed throughout the book in the rational manner that it deserves. The book draws attention not only to the idiosyncratic nature of each crop system and the effects of potential novel traits but also to the dramatic lack of scientific information in this field. This shortcoming makes it difficult to fully predict the likelihood and impact of ferality or volunteerism or the implications of growing plants with novel traits on these processes. Given that for as long as it has existed, agriculture has always had an enormous effect on the environment and that crops have always had the possibility to interact with neighboring crops, weeds, or wild relatives, this lack of research is surprising. It is also interesting that the advent of transgenic crops is largely responsible for the recent increased interest in addressing this gap and that molecular biology and transgenic plants themselves could play a significant role in this research, as exemplified by some of the authors in this book.
This book is an excellent resource for researchers as well as graduate and undergraduate students interested in the ontogeny, impact, and interactions of weeds. It would also be a useful reference to anyone wanting to learn more about the processes of domestication and dedomestication within agriculture, and how they may relate to the increased cultivation of transgenic plants.
Laurian S. Robert
Eastern Cereal and Oilseed Research Centre
Central Experimental Farm, KW Neatby Bldg.
960 Carling Ave. Ottawa (Ontario) Canada K1A 0C6
|Printer friendly Cite/link Email Feedback|
|Author:||Robert, Laurian S.|
|Date:||May 1, 2006|
|Previous Article:||Registration of a C/M doubled haploid mapping population of rice.|