Transgenic Sunflower - Genetics, Genomics and Breeding of Crop Plants - page 288

1969). Commercial sunflower hybrids were the outcome of breeding
techniques including interspecific crosses, induced mutation, marker-
assisted selection, as in other extensive crops. The improvement made the
crop a profitable and competitive option for Russia, Ukraine, and Argentina
(Chapter 1), comprising 51% of world production estimated in more than 32
million ton for 2008-09 (USDA 2009b).
In the beginning of the new millennium, there are no available GM
sunflower varieties for farmers around the world. Along with peanut - a
crop in which breeding is handled mostly by private companies (Frey 1996),
sunflower is among the five main oilseed crops that lack released transgenic
varieties. GM sunflower has been evaluated only under controlled
conditions, and its release for commercial use seems unlikely at present. Is
this a comparative disadvantage in relation to other oilseed crops? What
ecological, biotech, or economic constraints hinder release of GM sunflower?
How would GM sunflower modify the productive chain? How should GM
sunflower be managed to avoid undesirable environmental impacts? In
this chapter, we will try to answer these and other issues related to GM
sunflower.

9.2 Released Transgenic Crops

Among the 19 crop species transformed by genetic engineering and released
for extensive sowing, soybean, corn, rapeseed, and rice along with cotton
stand out because of the wide distribution of GM varieties expressing
herbicide tolerance (HT) and/or insect resistance (IR) traits (James 2008).
This process is the outcome of an intense biotech-based breeding activity
initiated in 1985, which only in the US involves more than 13,000
notifications and permit releases for field experiments (ISB 2007).
By far, the crop that has benefited the most from this novel technology is
corn. Among others, the planned IR for obtaining resistance against
European corn borer (ECB) Ostrinia nubilalis, can be considered one of the
most successful cases, where GM technology got rid of yield restraints. GM
corn with IR was obtained by transfer of a gene coding for Cry1Ab protein,
an insecticidal -endotoxin from Bacillus thuringiensis (Bt) that has been

used in pest control since the beginning of the last century. GM maize varieties
expressing Cry1Ab gene from Bt were available for the first time in the US
after approval of the MON810 event (Monsanto) in 1995. Overcoming the
difficulties for ECB control facilitated a fast adoption of this genetically
modified organism (GMO) including the European Union (EU) - one of the
environments where people largely reject usage of transgenics,- after
approval for sowing in Spain since 1998 (AGBIOS 2007).
The second highlight was soybean GM Roundup Ready® variety
(Monsanto 2002) tolerant to glyphosate herbicide (GL)—an inhibitor of the