Cisgenesis Does Not Solve the Late Blight Problem of Organic Potato Production: Alternative Breeding Strategies

Abstract

Average potato yields in Dutch organic farming systems vary from 15 to 29 Mg/ha and are limited by low input of nitrogen and severe late blight attacks caused by the oomycete Phytophthora infestans. Under Dutch late blight regulations it is mandatory to kill the haulm at 7% infestation. The late blight attacks have been so early in the organic potato production of the past few years that its acreage is now gradually decreasing whereas consumer demand is increasing. Agronomic control strategies have limited success. First priority lies in breeding for highly resistant varieties to safeguard organic potato production in the Netherlands. Cisgenesis, however, is not an option for the organic sector. Although the product of cisgenesis does not contain genes from non-crossable species it is a result of a genetic engineering process which is excluded from use in organic agriculture. As the principles and standards of organic agriculture are process-based, cisgenesis does not comply with the norms and standards of organic agriculture. The arguments of the organic sector go well beyond the alleged risks of the gene technology and relate to the technology itself. Breeding at DNA-level, instead of at whole-plant level, violates the integrity of life as described in the concept of naturalness. The Dutch organic sector is now aiming at increasing the traditional breeding activities including the participation of farmer-breeders in close cooperation with the formal breeding companies. Additional selection methods need to be developed to include required traits other than late blight resistance, such as nutrient efficiency. Recently

Understanding obstacles and opportunities for successful market introduction of crop varieties with resistance against major diseases

“…In the case of potato, the type of late blight resistance (the resistance gene, but also the method of breeding, e.g., genetic engineering or classical breeding, see Lammerts van Bueren et al 2008) is shaped by various elements, such as science, policy, culture, and the market, that together constitute the dominant socio-technical regime. New innovations may also develop at the niche level (Fig.…”

“…The large breeding companies aim to develop varieties that also do well in conventional farming to expand the area of sales per variety, whereas niche players primarily, though not exclusively, aim for organic agriculture. Through the development of new networks, which is important for the viability of the niche-players, organic farmer breeders often have innovative farming strategies and subsequent variety trait priorities different from those of conventional dominant socio-technical regime (Lammerts van Bueren et al 2008). Both categories may adopt new ideas from each other potentially leading to the development of joint approaches or new ideas (Nuijten et al 2012).…”

Debate on the Exploitation of Natural Plant Diversity to Create Late Blight Resistance in Potato

“…This involves a new paradigm of what durable resistance may imply (see also above) and how it can be used in combination with new ways to strategically manage resistance at the field, cropping system and landscape level. Many scientists claim that genetic modification of potato is a significant part of a breeding strategy aiming at the final solution of the late blight problem, preferably with cisgenes (Jacobsen and Schouten 2008), although there is significant resistance especially from organic agriculture where the late blight problem is most severe (Lammerts van Bueren et al 2008). This is further elaborated below.…”

“…Cisgenesis might give the potato breeding community the tool to finally combat P. infestans and stay ahead in the race against the oomycete. However, at this stage it is highly unlikely that cisgenesis will be accepted by the community of organic agriculture (Lammerts van Bueren et al 2008).…”

Why Organic Farming Should Embrace Co-Existence with Cisgenic Late Blight–Resistant Potato

“…An important question is how many crosses one should go back to assess whether undesired techniques were applied during the breeding process. The LBR variety Bionica which is recommended for organic farming [42] was indeed developed using chromosome doubling colchicine treatment.…”