WheatHub Student Webinar Series: Margaret Kirika
Sep 18, 1:00 pmFree
The ARC Industrial Transformation Research Hub for Wheat in a Hot and Dry Climate will be releasing an online Showcase event highlighting the work of the centre in October 2020. In the run up to the Showcase event, we are pleased to announce a series of research seminars given by our current and former PhD students. This webinar series showcases the excellent science our students have undertaken in last 5 years.
The next seminar will be given by Margaret Kirika at 1pm (Adelaide) on the 18th Sept 2020. See below for more details of Margaret’s talk.
Registration for the webinar is required. After registering, you will receive a confirmation email containing information about joining the webinar. If you are unable to attend, the webinar will be recorded and will be available as part of the online Showcase in October.
Webinar title: Understanding nitrogen uptake, partitioning and remobilization to improve grain protein content in wheat.
In cereals production, nitrogen (N) fertilizer management is necessary to maximize yield and grain protein content (GPC). Unfortunately, uptake of N fertilizers is low in wheat, necessitating the focus on improving N uptake/utilization and better N fertilizer management. In addition, there is a negative correlation between grain yield (GY) and GPC, with physiological traits correlating to this negative relationship not well understood. My PhD research focused on identifying the effects of foliar N application towards improving GPC. There was a significant increase in Gregory GPC following foliar N application at heading and seven days-post-anthesis (7 DPA). We also identified the leaf surface structures correlated to efficient foliar N uptake in four bread wheat genotypes Spitfire, Gregory, Kukri and RAC875 at stem elongation and 7 DPA. Trichome density, primary alcohols and alkanes were correlated to foliar N uptake at 7 DPA. Furthermore, a maximum foliar N absorption occurred in the first two hours of treatment, while the N form preferentially taken up as foliar was urea when compared to ammonium and nitrate, with the highest accumulation in the grain tissues. The leaf expressed N transporters were either upregulated or downregulated after foliar N treatment. There were negative feedbacks of foliar N application on root N accumulation and gene expressions of root nitrate transporters . Finally, to decipher the negative correlation between GY and GPC, we identified some physiological traits associated with the two important agronomic traits in 15 genotypes from a genetic diversity panel contrasting for GPC. In conclusion, we identified an N management strategy to improve GPC in wheat, as well as key physiological traits correlating to GY and GPC.