Tuesday 16 September 2014

uzu - Japanese barley in Shropshire


Firstly I haven't posted in a while - busy with harvest and now getting ready for the new term at Harper Adams.

I'm now using twitter for small updates and photos and this blog when I want to go into more depth than 140 characters allows.

My twitter handle is @naked_barley 

Earlier in the year I promised to explain what uzu barley is.

If you've seen The Seven Samurai (the Kurosawa original), you may remember that the villagers' plight is that that bandits have stolen their rice harvest and will come back to steal the barley, leaving the villagers to starve, hence the urgency to employ protection before the harvest.

In the double crop system traditionally used in Japan, mugi (winter corn) is sown after the rice harvest in October. Barley or rye are the preferred choices as they mature before the rainy season in June, and are then followed once more by rice.  

Most Japanese naked barley varieties grown as mugi are uzu types, which are dwarf varieties, with stiff straw, ideal for growing in fertile soils.  The uzu dwarfing gene confers insensitivity to brassinosteroids (BR), whilst Western dwarf barley uses genes such as sdw, conferring insensitivity to gibberellin (GA).

The uzu gene also causes the leaves to be short and erect and prevents the lower stems etiolating (extending) in response to shade - hence uzu barley may be suitable for high plant densities to suppress weeds.  

Grains of uzu barley are round and fat and ideal for a range of food uses.

So why not try uzu in the UK?

The problem is the lack of adaptation to the UK, especially to day length.  Anyone who's tried growing Oriental vegetables such as pak choi will have found that the long days in summer often cause the plants to flower (bolt).  Spring sown uzu barley sent to me by Mike Ambrose at the John Innes Centre when I was at Bangor did exactly this.  It produced ears very quickly without tillering (producing extra stems) and the biomass and yields were low.  Sowing in October produced better results, but Bangor's Henfaes Research Centre is near sea level on the coast and has very mild winters.  When I autumn-sowed uzu barley at Harper the Shropshire winter killed more than half the plants - back to the drawing board.

I crossed the Japanese Kitagawa Chobo with Westminster and the results were encouraging, except for a tendency for the stem base to be weak, so I crossed again onto Westminster (a backcross).

Now we can start to see the uzu trait in an adapted background.

The uzu plots are also darker green but the erect leaves let more light into the lower canopy - a more even distribution of photosynthesis.


Grains are excellent - specific weight of 80 kg/hl vs. 65-70 in 'normal' barley.