ATI in NILs with different Rht genes

The prevalence of wheat-related disorders increased during the last 50 years and it is still under discussion, if breeding is one reason for this increase. One key element of the Green Revolution was the introduction of reduced height (Rht) genes into wheat that decrease plant height and increase harvest index. One suggestion was that Rht genes increased the content of amylase/trypsin-inhibitors (ATI), which are important triggers of wheat-related disorders such as wheat allergy and sensitivity. To verify this assumption, near isogenic lines of four Triticum aestivum genotypes with five different Rht alleles/combinations and one tall control (rht) were analysed for the ATI content by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The absolute total ATI content was not affected by the Rht genes. In contrast, the proportion of total ATI based on crude protein was decreased by extreme dwarf Rht2+3 compared to tall rht, but semi-dwarf Rht1 and Rht2, dwarf Rht1+2 and extreme dwarf Rht3 showed similar proportions than tall rht. The same was observed for the most abundant and most bioactive ATI 0.19 and CM3. The ATI distribution was mostly affected by genotype and environment and hardly by allele. The analysis of three biological replicates, which were grown in three consecutive years, strengthen the findings that the semi-dwarf Rht genes that are present in modern wheat do not increase the ATI content.