Agronomic traits and deoxynivalenol contamination of two tetraploid wheat species (Triticum turgidum spp. durum, Triticum turgidum spp. turanicum) grown strictly under low input conditions

Abstract

An evaluation of the agronomic performance of two tetraploid wheat varieties ( Triticum turgidum spp. durum , Claudio ; Triticum turgidum spp. turanicum , Kamut ® ) grown strictly under low input conditions was carried out over three consecutive cropping years. The study reported grain yield values ranging from 1.8 to 2.6 t ha -1 . Productivity showed to be primarily affected by environmental conditions, while no differences were observed between the two genotypes. The study of the yield components highlighted that the durum wheat variety had a higher plant density than Kamut ® , but this discrepancy was offset by a greater number of kernels per spike and the kernel weight of khorasan wheat. The investigated wheat genotypes were also analysed to assess the mycotoxin (DON) levels of wholegrain semolina and the efficiency of cleaning treatments to reduce contamination. Results showed that both wheat varieties had a good hygienic and sanitary quality with a DON content ranging from 0.35 to 1.31 mg kg -1 , which was lower than the maximum acceptable level set by the European regulation at 1.75 mg kg -1 . In addition, our research work investigated the effects of premilling cleaning procedures, such as water washing and brushing, on mycotoxin levels, which yielded interesting results in terms of decontamination efficiency. These methods were particularly efficient with Kamut ® semolina (46-93% DON reduction), suggesting that mycotoxins accumulate in this variety at more superficial levels than in the durum wheat variety. On the whole, our study provided additional knowledge on the traits to be further improved to respond to low input requirements and to enhance the potential adaptability of wheat genotypes to organic agriculture. Our results emphasized the need to develop wheat varieties that can provide adequate performance without high levels of nitrogen inputs by selecting specific traits, such as kernel weight, spike length and kernel/spike. This may help achieve productivity gains in organic systems.