Author: Jeremy Cherfas

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Featured: Cassava research

Turns out we were ignorant. The CGIAR is doing a heap of work on cassava brown streak disease, as Clair Hershey informed us.

There are several major projects on breeding for resistance, e.g., ”Biotechnology applications to combat cbsd” coordinated by IITA; “Cassava genomics: bridging the gap between sequence and breeding application” funded by Gates; and an ongoing major effort in Uganda to look for resistance in landraces and bred varieties. Also, there is a new project proposal from East Africa to search for resistance in Manihot wild species. This is under review so details aren’t yet available, but hopefully it will be funded.

Which is great. But who knew?

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Those elusive pizzutelli, again

With thanks to Giuseppe for pointing out another fruit painter, I went looking for Bartolomeo Bimbi’s depiction of our current favourite grape, and found a reasonable version. I reckon that’s it fourth from the right in the third row down.

Unfortunately, on the version I found the names of the varieties, which I take to be somewhere within the escutcheon at the bottom of the painting, are illegible. Having looked at all the bunches hanging there, that’s the only one that does seem vaguely horn shaped. The original is in the Villa Medicea in Poggio a Caiano, about 15 km northwest of Florence, and if I’m ever in the area I’ll try and get a better look. Old paintings and manuscripts are clearly a good source of information for modern-day fans of diversity sleuthing, although I confess I rely on others more expert than me to do most of the legwork. A perfect example is Andrea Borracelli, whose website is full of this kind of information (and for which I am grateful).

From him, we learn that Galletta Bianca belongs to the group ‘Pizzutello’ for the characteristic shape of the berries, and was found 1 in the area of Montepulciano, growing in family gardens. It is an old Tuscan variety … described in 1809 by Targioni Tozzetti as having “acini corniculatis flavescentibus” — horn-shaped, yellow berries. Galletta Bianca (there is also a black form), differs from the known Pizzutello white, 2 is listed in the Catalogue of Betti (1851) 3 and in the catalogue for the Public Exhibition of the Horticultural Society of Tuscany (1858). Low (1982) lists Uva Cornelia as a synonym for Galletta Bianca. Vine of medium vigour, with normal (?) productivity, limited to the provinces of Siena and Arezzo. It has an average percentage of fruit set, with the first fruiting shoot on the third or fourth bud, with two inflorescences per shoot, and has a normal tolerance to the most common parasitic diseases.

And I reckon that’s about all the sleuthing we’re going to do, unless, of course, something even more interesting turns up.

Just for comparison, here are a couple of my own pictures of pizzutello bought just up the road a little more than a month ago.

Bimbi, by the way, clearly had a great interest in diversity; he also painted a two-headed lamb for Grand Duke Cosimo III de’ Medici.

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Featured: A history of synthetic rape

In pointing out that the resynthesis of oilseed rape goes back a little further than I originally thought, Toby Hodgkin offers a little more background on the whole story.

A general point is the importance of pre-breeding as part of the overall crop improvement process. It’s also worth commenting that the idea of resynthesis and hybrid transfers of useful genes in Brassicas was part of the breeding process at Scottish Plant Breeding Station, SCRI and in a number of European and American groups from the late 1960s on. There was quite a lot of interesting work on the relative merits of crossing at different ploidy levels, on the tissue culture processes to use and on the consequences of making the crosses in different directions and the results from subsequent backcrosses.

I hear that there is currently an interest in biofuel rapeseed. In this case the nasty biochemicals wouldn’t matter much while heterosis might be the real interest. Almost back to the start of the resurgence of rapeseed in the second world war in Canada – as a source of high quality (high erucic) oil for aeroplanes.

Who is capturing these memories?

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Who knows what about cassava brown streak disease

We asked why the CGIAR has apparently been so silent on Cassava Brown Streak Disease. Glenn pointed out that maybe we’re just ignorant.

There is probably more going on, we just don’t know about it. One key question is whether genebanks have been thoroughly screened for CBSD resistence.

Well, have they?

Glenn makes another good point.

In theory, CG reform should be able to tackle a problem like this more efficiently. The roots and tuber program should be promoting more interaction between IITA and CIAT, interaction that would bring together the researchers mostly closely working on CBSD with others that might have solutions … maybe someone who know more about this can comment.

Well, can they?

But caught up in the frenzy, Glenn cannot help but post a little something on CBSD himself, thus finally breaking that CGIAR silence. Our next question? Why doesn’t FARM-Africa mention the disease in their post, also today, on their cassava work in Western Kenya? The disease is just across the border in Tanzania, after all, according to Glenn’s maps.

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Nibbles: New cassava, CBSD maps, Research, Pest management, Banana research