What kind of a timescale are we talking?

Let's say, hypothetically, that GM crops were deemed to be the way to ensure future food security in the face of climate change, how long would they take to integrate into common agricultural practice? As I found out whilst writing the last post, there are many reasons why GM crops will not work in some areas of the world, so this is looking at places were GM crops could potentially be socially, economically and ecologically viable.

Godfray et al., 2010, collated some studies into a table which looks at how long it will take to develop different desired crop traits in different crops, some of which could help mitigate the impacts of climate change on food security in the future.

Source: Godfray et al., 2010: 815.

In terms of direct impacts of climate change on agriculture, increasing drought-tolerance and salinity tolerance will be some of the most important to help maintain agricultural production. However, this study does not anticipate these traits to be achievable until at least 2020, potentially 2030. 

The IPCC suggests that the 'proportion of the lands surface in extreme drought...is set to increase from 1-3% for the present day to 30% by the 2090' (IPCC, 2007:WWW), indicating a very rapid increase in 'extreme' events within this century. In 2015, transgenic strains of rice with increased drought-tolerance were undergoing trials and some studies such as Todaka et al., 2015 have reported an improvement in tolerance. However, the Todaka et al., 2015 study also points out how genetically modified species are likely to need to be drought and flood resistant, due to the fluctuating nature of extreme climate. So trials are underway with drought and flood resistant rice species, but it is difficult to know how long the further research which is called for will take.

Increased soil salinity as a result of rising sea levels induced by global warming means that in order to maintain productivity, crops will need to be able to tolerate more salt (Shrivastava and Kumar, 2015). This study by Yamaguchi and Blumwald, 2005, states that one of the factors which is slowing the development of increased salinity tolerant crops is an incomplete understanding of the 'fundamental mechanisms of stress tolerance in plants' (p615). The authors feel that the development process can be sped up by looking at different combinations of genes from salt-tolerant plants, though a timescale is not given.  Roy et al., published a study of all known salt tolerant genes in their 2014 study, and highlighted how these 'mechanisms of salinity tolerance' (p116) now need to be applied to crops to start to see the benefits of improved salt tolerance on productivity.