Plant Population and Management Effects On Agronomic Performance and Milling and Baking Qualities of Winter Wheat.

This is a two year study to evaluate genetic by environment by management variation in winter wheat production in Indiana.  Seven winter wheat lines with varying genetic resistance to barley yellow dwarf virus were planted at two seeding rates (377 and 485  seeds per m²), under each of six management regimes at West Lafayette and Evansville Indiana.  The six management regimes consisted of nitrogen fertilizer application rates and presence or absence of seed treatment, insecticide and fungicide.  The grain yield, milling quality and economic cost-benefits were analyzed for each treatment.  Preliminary results show that line, location, nitrogen, seed treatment, and fungicide all had significant effect on yield at α<0.001 while seeding rate was significant at α=0.05.  Insecticide was not significant, given the general absence of insect infestation in these seasons and locations.  The only highly significant (α<0.001 ) interaction was line x location; line x nitrogen level was significant at α=0.1.  Tukey tests show that 151kg ha^-1  N topdress resulted in  6.99 Mg ha^-1 grain yield and 106 kg ha^-1  N topdress yielded significantly different 6.13 Mg ha^-1, which is a significant difference at α=0.05. The higher nitrogen fertilizer and plant population had significant effects on both yield and grain quality.  Data from the 2009 harvest shows that high N fertility statistically increased flour protein, but it was not a substantial amount, (<0.05g protein/100 g flour). The high fertility treatment also decreased the grain softness equivalent, although it was a small effect; this effect did not affect gluten strength as measured by lactic acid Solvent Retention Capacity (SRC).  The least significant effect was in cookie top grain, which is a visual assessment.  This study did not identify significant cultivar x management interactions for milling and baking qualities, indicating that higher production management for increased yield does not dramatically alter flour qualities. Economic analyses of the earning potential for each management regime are also being performed.