“In domestic markets, chalk can devalue the grain by up to 25 per cent and in international markets by up to 30 percent. And aside from the mAside from monetary value, chalk reduced the amount of edible grain a farmer will take back home from the mill.
So chalk has a huge impact and it is something we’ve never been able to eliminate in a breeding program.
We have varieties that are chalkier than others but every variety is sensitive to high temperatures which have the effect of speeding up the plant’s growth. This reduces the time available for grain filling … and of course in a warming world this is going to become an increasing problem.
So the research objective is to eliminate chalk because there is a genetic component to the trait.
In our research we have two varieties, one that is chalky all the time and one that is only sometimes chalky. With the less chalky variety we have fund that early in grain filling it ‘detects’ any high temperature levels and aborts the production of spikelets. In other words it limits the number of grains, or matches the grain produced with the plant’s inner resources to ensue that what grain does fill is complete.