Angela Merry1, Tina Botwright Acuña2, Penny Riffkin3, Richard Richards4
1Tasmanian Institute of Agriculture, School of Land and Food, University of Tasmania, Private Bag 46, Kings Meadows
Tasmania, 7249, Angela.Merry@utas.edu.au
2Tasmanian Institute of Agriculture, School of Land and Food, University of Tasmania, Private Bag 54, Hobart, Tasmania, 7001.
3Department of Economic Development, Jobs, Transport and Resources Victoria, PB105 Hamilton, Vic, 3300.
4CSIRO Agriculture Flagship, GPO Box 1600, Canberra, ACT, 2601.
It is proposed that an erect leaf-type might intercept more radiation, have greater radiation-use efficiency (RUE), and thus produce greater yields of wheat in the High Rainfall Zone (HRZ). A field experiment was undertaken in Cressy, Tasmania in 2016. Five of each erect and planophile lines, selected from the CSIRO wheat Multiparent Advanced Generation Inter Cross (MAGIC) population, were sown at three plant densities (100, 200 and 300 plants/m2) with three replicates. Planophile lines intercepted more light and had a greater leaf-area index (LAI) and aboveground dry matter (DM) at anthesis than erect leaves, which translated into a higher normalised difference vegetative index (NDVI). At harvest, planophile lines were taller and had greater stem DM and aboveground DM, but grain yield was the same as for erect leaves. Planophile lines had greater ear DM at harvest at low plant densities. Plant density otherwise had limited impact on yield and components of yield. Although leaf erectness is potentially a trait that is easy to target in breeding programs, it appears that planophile leaves may be more adaptive in this cool temperate environment. Further experiments across different sites and seasons are required to improve our understanding of the potential for leaf architecture to contribute to yield in the HRZ.