GMO Apomixis and Terminator on Biological Diversity

 You can’t really do a grammar check without some semantics. What is Apomixis? Trends in Plant Science explains.

Most plant species produce genetically variable seeds by the fusion of meiotically reduced egg cells and pollen grains. However, a small proportion of seed plants produces clonal, asexual seeds by the process of apomixis. The fixation of heterosis by apomixis is of great interest for plant breeding. The prospect of changing sexual crop species into apomictic crop species by genetic engineering – apomixis technology – has recently caused a boom in apomixis research. According to evolutionary biological theories, a dominant apomixis gene will rapidly become fixed in an outcrossing sexual population. Therefore, in theory, apomixis transgenes could have unconditional advantages that could result in the uncontrollable spread of the transgenes. By contrast, ‘classic’ transgenes might only have conditional advantages. Paradoxically, sexual reproduction and not apomixis is common in nature. However, this is no guarantee that apomixis transgenes will be ecologically safe because there could be essential differences between natural and transgenic apomicts.

This sets off alarm bells. Colin Tudge‘s delightful The Tree: A Natural History of What Trees Are, How They Live, and Why They Matter,and just about anyone will speculate, sexual reproduction and evolution are probably spurred by disease, those microbes that corporate food systems and globalization giving the upper hand to. So when Trends in Plant Science warns that "apomixis transgenes could have unconditional advantages that could result in the uncontrollable spread of the transgenes," you have to worry about loss of disease-defying genetic diversity, not only in crop plants but also in the wild varieties that let us maintain existing and develop original food varieties. Grain.org’s 2001 Seedling article Apomixis: The Plant Breeder’s Dream maps out the issues.

The introduction of apomixis into crops would alter the genetic diversity of both crops and their wild, non-apomictic relatives. What the result would be nobody knows, because apomixis is so poorly understood. This makes predictions on apomixis’ impact on biodiversity highly speculative, and even contradictory. The first image apomixis conjours up is uniform fields of clonic plants. More uniform than current monocultures, these crops will be more fragile, and more susceptible to pest and disease pressures. This will lead to an accelerated genetic treadmill to keep pest and diseases at bay. Some authors think that the low rate of apomixis in nature might be the result of extinction brought about by its long-term disadvantages.

The journal Nature informs that this "Living Pollution" contamination of isolated varieties of corn has already been seen in Mexico. Vandana Shiva points out that even Prince Charles recognizes the issues with gmo and food security. Colin Tudge book Feeding People is Easy looks like a hybrid of Michael Pollan (navigate the treacherous landscape of the American supermarket" with him on DN!)and FoodFirst. Why do people even bother with genetic engineering? Unless you’re a psychopathic corporation you’ll probably want a world where people can eat papayas or something with vitamin A in it instead of forcing rice to save people’s eyesight. I guess that is the key to understanding genetically modified organisms though, corporate control. Although a book review of Brave New Seeds in The Journal of Political Ecology gets tacky aiming for balance, even the vaguest awareness of Monsanto suing a Canadian farmer for harvesting rapeseed polluted with patented GMO genes crushes Stone’s cool. This paragraph makes me want to hold him down with Jimmy Carter while Vandana Shiva smacks some sense into them.

The book exemplifies the regrettably polarized character of the debate on GM crops. This has turned into a spin war that pushes both sides to devious positions (Stone 2000): corporate media touts a disingenuous malthusianism and inflated claims on the humanitarian benefits of their products, while green critics obstinately deny that GM crops have any promise whatsoever. A case in point from this book is the issue of apomixis — the property of asexual reproduction, occurring naturally in some plants and apparently transferrable to new plants. While GM today is widely associated with "Terminator" technology which would remove farmer control over seed reproduction, the development of apomictic plants through genetic modification would allow increased farmer control. All hybrid seeds are "terminator" seeds in that heterosis (hybrid vigor) is lost in the second generation. But apomixis could lock the benefits of heterosis into a replantable pure line. Progress has been slow using conventional breeding techniques, and genetic modification promises to greatly expedite research. It is not yet known how this apomixis technology will affect farming in the south (Bicknell and Bicknell 1999), but clearly the potential is enormous. Remaining true to the polarized debate, Brave New Seeds claims apomixis to be no more than a means for seed companies to reduce production costs, while reducing plants’ capacity to adapt to changes in the environment (p. 35). Another example: researchers in non-commercial labs have developed cassava resistant to the mosaic virus that ruins part of the African harvest each year; this is a vegetatively reproduced crop that could remain outside of corporate control. How these technologies are deployed, and how we are to weigh their risks and benefits, are crucial issues for agriculture in the south, certainly deserving of a more open-minded airing than they receive here.

Why go for balance when dealing with psycopaths?

…the apomixis research agenda is being up led by the private sector through patent applications, licensing agreements and confidential research projects.

…in nature, apomixis is widespread but infrequent: it occurs in around 10% of the 400 families of flowering plants, but only in 1% of the 40,000 species that make up those families. Apomixis is most frequent in Gramineae (the cereal family), Compositae (which includes sunflowers), Rosaceae (which includes many fruit trees) and Asterceae (the dandelion family). Only a handful of crops are apomictic: citrus, mango, some tropical forages and a few others.

Apomictic plants produce cloned seed, enabling them to reproduce asexually. But their pollen is often viable, so that apomixis can also be transmitted through the more common mechanism of sexual reproduction. Like genetic engineering, apomixis would demolish some of the species barriers that have contained the evolution of our crops. The combination of apomixis’ capacity to create and stabilise new genetic combinations and to break the species barriers could lead to the "asexual revolution", which some think could even dwarf the Green Revolution. The question of who controls or owns apomixis will determine the impact apomixis has on farmers, breeders and the seed industry. If made available in the public domain, apomixis would likely result in a general decrease of seed prices, and in a steep increase in the varieties available to farmers. If one or a few companies control apomixis, the effects would be radically different. Apomixis-led savings in variety development could allow the companies in control of the technology to push competitors out or impose abusive licensing conditions. But apomictic seeds would still be hybrids, which means they would demand dependency on fertilisers and pesticides. Like other hybrids, apomictic hybrids would still be designed to perform their best under certain environmental conditions, which small farmers are unlikely to achieve and maintain. Apomixis might increase farmers’ access to hybrids, but not their control of them.

….Many people working directly with farmers think that existing approaches to participatory plant breeding would be much more helpful. From her work on participatory breeding with Brazilian family farmers, Angela Cordeiro has learnt that skilled farmers breed for variability rather than yield, to afford security in the face of unpredictable environmental conditions. The stability and fixation entailed by apomixis is alien to small farmers’ traditional strategies. In addition, Cordeiro’s work has demonstrated that yields in traditional, open-pollinated maize varieties are limited by bottlenecks in soil management and seed storage, rather than genetic potential.

….One of the significant threats to farmers getting any benefits from apomixis is the potential use of Traitor/Terminator Technologies, also known as Genetic Use Restriction Technologies (GURTs). Because in principle apomixis would allow farmers to save hybrid seed, it has been touted as the antidote to Terminator, which renders seeds sterile. However, seed companies will only capitalise on apomixis if they prevent farmers and competitors from obtaining clones from apomictic varieties. It seems likely that companies will use GURTs in conjunction with their apomictic varieties, just as they plan to do with other seeds. As a result, apomixis would not be an antidote to the Terminator: it would simply complement it.

A request for a grammar check on a genetic engineering paper led me to a fascinating subject. I went from not knowing what an Apomict was to not wanting to contribute to research creating gmo apomict seeds.

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