Double defence
The parasitic plant Striga, or witchweed, is a disaster for lots of sub-Sahara African farmers. Striga does what any parasite does, it taps water and nutrients from its host. Something that in agriculture result in big losses. Sometimes the whole harvest is lost. Now Kenyan researchers together with researchers from the USA, Germany and Australia discovered that Striga resistant plants use two strategies.
But first the reason that makes from Striga such a devastating parasite. This is due to the fact that a single Striga plant is producing up to 50000 seeds. These seeds stay inactive in the soil up to the moment they perceive a favourable host plant. Even if that means they need to wait for tens of years. Something that gave Striga the nickname ‘witchweed’. Now luckily there are also plants that are resistant to Striga.
Striga resistant plants do everything in their power to keep Striga out
The researchers studied five of these resistant sorghum plants. They noticed that these plants applied two strategies. The first strategy is the erecting a mechanical barrier. The cell walls of these plants are extra strong. The second strategy the researchers observed is controlled cell death of those cells that are located there where the parasite contacts its host.
The researchers subsequently studied the effect of a striga infection on the gene regulation in those resistant plants. This showed that most plants activated both the mechanical and the cell death defence method. Although, the strength of each of those defence methods differed between the resistant plants.
Striga resistant plants do everything in their power to keep Striga out. This work demonstrates which strategies these plants use, and more importantly it identified which genes are needed for this defence. Breeders can apply this knowledge in their effort to develop other Striga resistant sorghum varieties. To increase the chance of a good harvest.
Literature
Sylvia Mutinda, Fredrick M Mobegi, Brett Hale, Olivier Dayou, Elijah Ateka, Asela Wijeratne, Susann Wicke, Emily S Bellis, Steven Runo (2023) Resolving intergenotypic Striga resistance in sorghum, Journal of Experimental Botany, Volume 74, Issue 17, Pages 5294–5306, https://doi.org/10.1093/jxb/erad210
Plant en Zo 