Deoxynivalenol Concentration and Grain Quality of Fusarium Infected Winter Wheat Genotypes under Restricted Water
V. C. Okereke
Department of Crop and Soil Science, University of Port Harcourt, Port Harcourt, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
A field experiment after maize factorially combined shelters and six wheat genotypes varying both in the presence of reduced height (Rht) alleles, known to vary for linked Type II resistance to Fusarium infection, photoperiod sensitivity (Ppd-D1) and baking quality: Oakley (Rht1-B1b + Ppd-D1b), Soissons (Rht1-B1b + Ppd-D1a), SR 53 (Rht1-D1b + Ppd-D1a), SR 94 (Rht1-D1b + Ppd-D1b), Maris Widgeon1 (Rht1-B1b + Ppd-D1b) and Maris Widgeon 2 (Rht1-D1b + Ppd-D1b) in four completely randomised blocks. Shelters were applied from the end of anthesis until 28 days later. Plots were sampled after shelter removal (hand harvest) and also at maturity (combine harvest). Analysis was carried out on the harvested grains which included deoxynivalenol (DON) concentration and grain quality parameters such as crude protein, Hagberg falling number (HFN) and sedimentation volume (SDS). Data show that in hand harvested grains, there was significant (P=0.01) genotype x shelter effect where shelter reduced DON concentration by 48% in Soissons. Crude protein (P=0.08), HFN (P=0.08) and SDS (P=0.19) showed no genotype x shelter effect. In combined harvested grains, DON concentration showed no clear pattern. However, crude protein (P=0.005) and HFN (P=0.034) showed significant genotype x shelter effect where shelter reduced the crude protein in Oakley and increased HFN in Maris Widgeon genotypes. This study therefore, reveals that data on the level of DON contamination may not be deduced from results of HFN, SDS volume or protein content, thus these parameters may not be influenced even when wheat kernels are heavily infected by Fusarium even under restricted water during grain filling.
Keywords: Deoxynivalenol, genotype, shelter, crude protein, Hagberg falling numbe, sedimentation volume.