Sunday 22 March 2015

Soil-building wheat


Out of curiosity I grew some Rampton Rivet alongside the Holdfast shown in a previous post.

Rivet wheat (Triticum turgidum sbsp. turgidum) is a tetraploid wheat, related to durum (T. turgidum sbsp. durum) and was grown up until the Second World War.  Another name for it is English Wheat, although it appears that common or bread wheat (T. aestivum) was always the most important (Bell, 1948).

Rivet was recommended for "clay soils of low fertility", whilst the high yield and quality bread wheats such as Holdfast are suited to "land in good heart" (Stapledon and Davies, 1948).

Rampton Rivet was an improved selection from the Rivet landraces of Cambridgeshire, and was very much last of the line.  Rivet is no longer grown commercially in UK, except on a very small scale.  

Having seen differences in rooting between modern wheat and spelt, and reading about Rivet's suitability for clay, I expected the root system to be better than modern wheat. I was still shocked by the contrast.
On the left is Skyfall, a modern variety; on the right is Rampton Rivet.  Both were sown at the same time and grown in the same glasshouse.  Skyfall is a superb modern variety, with a yield to match barn-filling feed varieties, high quality grain and a good agronomic package.  Rivet on the other hand is a machine to pump carbon into the soil, with thick, deep scavenging roots and a mass of fine roots.  The straw is also very coarse, therefore a good source of the lignin that feeds beneficial soil fungi that are often deficient in our soils.

Have we lost something here?  Is there a place for crops that help keep the soil in "good heart"?

References
Bell G.D.H. (1948). Cultivated Plants of the Farm. Cambridge: CUP
Stapledon R.G. and Davies W. (1948). Ley Farming. London: Faber
http://www.dovesfarm.co.uk/resources/whats-new/interview-with-archaeobotanist-john-letts/

Thursday 19 March 2015

Breeding the 'perfect' naked barley

I've been lucky to be allowed some time to indulge in unfunded hobby breeding at Harper Adams, but why isn't this work being done by a proper plant breeder?  The answer is that nearly all plant breeding in the UK is done commercially,  paid for by breeders' rights and and so breeders get paid for every tonne of seed sold or saved on farm.  Therefore it simply isn't economic to breed niche crops like naked barley or spelt - far better to go for the next barn-filler feed wheat.

My system is simple and low-tech:

1. Choose parents and make the cross
2. Grow the F1 plants in the glasshouse to get as many F2 seeds as possible (2000-3000 ideally).
3. Grow a plot of F2 in the field
4. Select the best naked grain ears and keep a sample of the remainder
5. Grow 10-20 of these selections over-winter as F3 in the glasshouse
6. Bulk the selections back (discarding any 'rejects' and keeping any really promising back for single-seed descent
7. Sow a plot of the F4 selections and a plot of the bulk F3 to allow further selections - don't want to discard too much too soon.
8. Mass select the F4 plot - e.g. remove talls, weak plants, diseased plants and repeat mass selection in following years.

By doing this, I've now got several mass-selected, fairly uniform populations for replicated yield trials plus some pure lines derived from single plant selections.



The photos are of some of the mass-selected plots in 2014, looking fairly uniform and an ear of a pure line coded S9.  I'm quite hopeful about this line as it has fragile pales that release the grains easily when threshed to give a very clean sample.