Competition Entry

Robert Hijmans writes:

I would like to submit this video to the competition:

I believe it is great example of agrobiodiversity at work; and why we have genebanks, screening, and (molecular) breeding programs.

The video shows IR64, a widespread rice cultivar, and IR64-sub1 growing side by side on a field at IRRI that experiences a (simulated) flash flood. IR64 is badly affected, IR64-sub1 comes out much better.

These are essentially the same varieties. IR64-sub1 is a so-called “near-isogenic line” of IR64, but with the “sub1” gene. IR64-sub1 was obtained through conventional crossing and back-crossing with IR64; aided by a molecular marker for this gene (to check which of the offspring have the gene and which not). See this (paywalled) paper for the science behind it.

The sub1 gene confers tolerance to submergence (roughly speaking, plants can survive 2 weeks, rather than 1 week, under water). The gene occurs in some rice landraces, but these are not very popular because of low yield/quality. However, when the gene incorporated into otherwise more attractive cultivars, these can be of great help to farmers whose fields are submerged during the growing season, which is an significant problem for rice production in South and Southeast Asia.

I think this is a preview of what many breeding programs will be about. Take a generally high yielding, good quality variety and start adding additional characteristics, such as tolerance to floods, drought, salinity, a bug, etc. For a single trait this can be done by crossing and back-crossing, but later by transformation, because the marker assisted back-crossing will become too cumbersome if one wants to keep track of many traits.

Disclaimer: I did not make the video (but I do want the iPod!).