A scientific literature study
In the last
blog I wrote about upcoming challenges in Swiss agriculture. One of the main
subjects was the climate change and all its related issues like hotter and drier
summer or water scarcity. In todays blog I’m going to write about water
shortage and how this problem is being approached nowadays.
Specifically
the focus will be on the transgenic plants efficient use of water. My reference
article was written by Eleonora Cominelli and Chiara Tonelli at the University
of Milan with the title “Transgenic crops coping with water scarcity”.[1]
I chose
this paper as it is written in an understandable and still scientific way.
Furthermore, it gives a good overview of the basics of genetic modification of
plants in general and related to water stress in detail.
Cominelli
and Tonelli are stating the availability of water or more specific its absence
as one of the main causes of limited crop harvest worldwide. As environmental
factors or water situations are not changed that easily the authors see
promising possibilities in genetically modified plants. Therefore, they name
two different goals: develop plants that have improved water use efficiency and
improved drought resistance. These goals are approached by manipulating the
plants osmoregulation. In general this is achieved by inserting genes that lead
to an overproduction of osmoprotectants or an overexpression in transcriptional
regulators. Transcriptional regulators are often involved in plant reactions to
drought stress. Moreover, a plant mutant is mentioned in the paper that has
increased stoma closure and reduced stoma density what results in better
drought tolerance.
All the
approaches mentioned have successfully been tested on thale cress (Arabidopsis thaliana). Thale cress is
not used commercially and often being considered as weed. However, prosperous experiments
have been carried out with maize and rice too. Other papers also named tomato,
tobacco plants, barley, wheat, soybean and potato as being affected by water
scarcity and suitable plants for these methods.[2],[3],[4],[5]
For Swiss
agriculture wheat, barley, maize and tomato are the most interesting ones. Nevertheless,
personally I think scientific research focus should be on wheat, rice and
potato as these are staple food to millions of people worldwide. Furthermore, a
well-developed country like Switzerland with agriculture in comparably small
scale might also be interested in alternative solutions like drip irrigation
(Tröpfchenbewässerung), as already practiced with hors-sol tomatoes for
example.
References
[1] Cominelli E. and Tonelli C.
(2010). Transgenic crop coping with water
scarcity. Found 12.04.2014 on Pubmed: http://www.ncbi.nlm.nih.gov/pubmed/?term=transgenic+crop+coping+with+water+scarcity
[2] Begcy K. et al. (2011). A
novel stress-induced sugarcane gene confers tolerance to drought, salt and
oxidative stress in transgenic tobacco plants. Found 12.04.2014 on Pubmed: http://www.ncbi.nlm.nih.gov/pubmed/?term=A+Novel+Stress-Induced+Sugarcane+Gene+Confers+Tolerance+to+Drought%2C+Salt+and+Oxidative+Stress+in+Transgenic+Tobacco+Plants
[3] Bahieldin A. (2005). Field
evaluation of transgenic wheat plants stably expressing the HVA1 gene for
drought tolerance. Found 12.04.2014 on: http://onlinelibrary.wiley.com/doi/10.1111/j.1399-3054.2005.00470.x/abstract
[4] Quan R. et al. (2004). Engineering
of enhanced glycine betaine synthesis improves drought tolerance in maize. Found
12.04.2014 on Pubmed: http://www.ncbi.nlm.nih.gov/pubmed/?term=Quan%2C+R.+et+al.+%282004%29+Engineering+of+enhanced+glycine+betaine+synthesis+improves+drought+tolerance+in+maize.+Plant+Biotechnol.+J.+2%2C+477%E2%80%93486
[5] Hu H. (2006). Overexpressing a
NAM, ATAF, and CUC (NAC) transcription factor enhances drought resistance and
salt tolerance in rice. Found 12.04.2014 on Pubmed: http://www.ncbi.nlm.nih.gov/pubmed/?term=Hu%2C+H.+et+al.+%282006%29+Overexpressing+a+NAM%2C+ATAF%2C+and+CUC+%28NAC%29+transcription+factor+enhances+drought+resistance+and+salt+tolerance+in+rice.+Proc.+Natl.+Acad.+Sci.+U.+S.+A.+103%2C+12987%E2%80%9312992
