Plant Cuttings

Small is beautiful… and more feminine…

Image: Loren Frølich, from Den ældre Eddas Gudesange by Karl Gjellerup, 1895.
Image: Loren Frølich, from Den ældre Eddas Gudesange by Karl Gjellerup, 1895.

Do our crop plants have to be as big as they are? Eh? Well, not such a daft question as you might think. Searching for a more cost-effective (i.e. cheaper!) alternative to inhibitors of brassinosteroid (BR) biosynthesis to study the role(s) of BRs in plants, Thomas Hartwig et al. propose the fungistat propiconazole (Pcz) as a suitable replacement. At US10 cents a gram it is considerably cheaper than the price tag of US$25,000 for the same amount of brassinazole (Brz) – the usual BR synthesis inhibitor of choice (of the Hobson’s variant). What has this to do with smaller crop plants? Well, this discovery comes on the back of previous work from Hartwig et al. demonstrating that mutation-induced loss of BR synthesis in maize not only dwarfs the plants but also ‘feminizes the flowers’. Hence a cheap BR synthesis inhibitor – such as propiconazole – could be applied to some crop plants to keep ’em small and also promote female flowers – the only ones that ultimately produce the harvestable seed crop. And… the propiconazole is not harmful to humans because, ‘They treat golf courses with it. People are around it every day’, according to Burkhard Schulz, a Purdue University assistant professor of plant biochemical and molecular genetics (and last author on the two cited research papers). And if GM versions of these crops were ever used, they should not stir up the passions of over-zealous anti-GM protesters because – being male sterile (the plants!) – there is no risk of GM pollen contaminating the countryside, in Hertfordshire (UK) or elsewhere. Result! Or, as the PLoS One article’s team concludes, ‘The reduced cost and increased availability of Pcz, compared to Brz, opens new possibilities to study BR function in larger crop species’. Now, and not that this item is in any way ‘inspired’ by the 2012 Olympics and reminders of the Olympics of the Cold War era when two Germanies competed against each other often amid acrimonious accusations of steroid abuse to boost performance of certain competitors, but… for a review on the prospects of boosting crop yields with plant steroids, see Cécile Vriet et al. (The Plant Cell 24: 842–857, 2012). Of course, an old-fashioned way of achieving all this performance-enhancement is to cross-breed different individuals and make use of good old hybrid vigour (or heterosis as we used to call it). Well, I’m sure interest in this technique will be renewed now it has been demonstrated (legitimised?) by the crossing of two Arabidopsis lines, as Ryo Fujimoto et al. reveal increased photosynthetic capacity in a cross between Columbia-0 and C24 accessions.

About the author

Nigel Chaffey

Nigel is a botanist and full-time academic at Bath Spa University (Bath, near Bristol, UK). As News Editor for the Annals of Botany he contributes the monthly Plant Cuttings column to that august international botanical organ. His main goal is to inform (hopefully, in an educational, and entertaining way...) about plants and plant-people interactions.