Replicated and randomised wheat (Triticum aestivum L.) cultivar trials were conducted in moderate to low rainfall zones at Wagga Wagga (572 mm) and Condobolin (449 mm) NSW, respectively in 2014–2016. At each experimental site, crop and/or weed growth were monitored at selected growth stages including tillering, vegetative, grain filling, harvest and after crop harvest. In addition, shoots, roots, rhizoplane and bulk rhizosphere soil samples were collected for metabolomics profiling and biomass evaluation. Plant tissue samples were extracted in methanol using an automated Buchi high pressure extractor while soil samples were extracted using a rotary shaker. Extracts were filtered and specifically analysed for unique secondary metabolites or allelochemicals associated with weed suppression, specifically benzoxazinoids (BXs), using liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-MS QToF). Metabolic profiling of wheat shoots, roots, and soils resulted in detection of up to 14 individual BXs including BX glycosides, lactones and hydroxamic acids of interest. Both qualitative and quantitative differences in BXs were observed and were cultivar-, growth stage- and location-dependent. Plant part and rhizosphere location (distance from root) also impacted BX concentration. Further metabolic profiling provided crucial information regarding crop metabolism, as well as the biosynthesis and release of metabolites associated with weed suppression in currently available commercial wheat cultivars, in contrast to weed suppressive rye (Secale cereale L.) and a heritage wheat cultivar Federation, both recognised for their potent ability to suppress weeds. We conclude that certain commercial wheat cultivars maintained high yield potential and were significantly more weed suppressive, depending on year and location, due to both their early growth habit and canopy architecture as well as the release of BX metabolites into the rhizosphere over time.
|Number of pages||1|
|Publication status||Published - 2018|
|Event||21st Australasian Weeds Conference 2018: Weed biosecurity - Protecting our future - Novotel Sydney Manly Pacific, Manly, Australia|
Duration: 09 Sep 2018 → 12 Sep 2018
http://caws.org.nz/old-site/awc_contents.php?yr=2018 (conference proceedings)
https://abercrombie.eventsair.com/QuickEventWebsitePortal/21awc/21awc-web/Agenda (conference program)
|Conference||21st Australasian Weeds Conference 2018|
|Period||09/09/18 → 12/09/18|
|Other||The Weed Society of New South Wales Inc., on behalf of the Council of Australasian Weed Societies Inc., will be hosting the 21st Australasian Weeds Conference in the popular Sydney beach side suburb of Manly from 9 - 12 September 2018. An assortment of field trips will be hosted on Thursday 13 September 2018.|
This biennial conference carries on a long tradition of bringing the weed management community together to discuss new developments and share information about cutting-edge and best weed management practices.
The conference attracts over 250 delegates from across Australasia and globally. Delegates will come together to network with peers, engage with industry sponsors, listen and participate in presentations and field trips on a variety of topics including;
- New technologies in weed management.
- Biological, mechanical, and chemical weed control and research.
- Herbicide resistance.
- Weeds of crops and pastures.
- Environmental weeds and Weeds of National Significance.
Mwendwa, J. M., Weston, P., Fomsgaard, I., Laursen, B. B., Brown, W., Wu, H., Quinn, J., Weidenhamer, J., & Weston, L. (2018). Metabolic profiling for benzoxazinoids in weed suppressive and early vigour wheat genotypes. 146. Abstract from 21st Australasian Weeds Conference 2018, Manly, Australia. http://caws.org.nz/old-site/awc/2018/awc201811461.pdf