Senay Simsek Research Website


Wheat Quality Projects

Impact of Pre-harvest Desiccants on Wheat Quality

Glyphosate is the most widely used herbicide in the world. It is a non-selective, broad spectrum, post-emergence herbicide, therefore controls a wide range of different species. Although glyphosate is effective in weed control, side effects of this herbicide on the crop itself, micro and macro organisms and plant diseases have been reported. As such, in the context of public health and environmental issues, use of glyphosate has been a compelling issue during the last few years.

In a study conducted to determine the effect of pre-harvest application of glyphosate of grain quality, it was found that glyphosate at a level of 1.0 kg/ha decreased the germinations energy and the length and weight of primary roots, and when applied at 2 kg/ ha, glyphosate decreased the thousand kernel weight. The study also found that wheat desiccation using this herbicide limits the emergence and weight of seedlings. Moreover, glyphosate drifts to non-target crops, resulting in growth aberrations and reductions in yield.  In addition to yield loss, glyphosate also causes many negative side effects. Glyphosate was found to decrease the fresh weight of seedlings in this study and inhibit the production of basal buds at the optimum temperature. In this context, the aim of this study is to determine the effect of glyphosate on hard red spring wheat cultivars grown in North Dakota. Effects on end-use quality, starch, protein and arabinoxylan chemistry would be studied.

Fusarium Head Blight and Metabolomics

Fusarium Head Blight (FHB) also named "scab" has been a persistent problem in small grains for many years with worldwide outbreaks. In North America, notorious epidemics during the 1990s have made devastating economical effects. Although the pathology of the disease is not completely understood at the molecular level, recent advancement in technology has brought up the study of the metabolome that covers the network of biochemical interactions, including those of host-pathogen nature. In this work, three North Dakota released wheat varieties and two Near Isogenic lines were infected with Fusarium graminearum. Infected florets were collected cryogenically in a time course fashion making composite samples. The tissue will be analyzed using an LC QTOF/MS to sort and identify the compounds in wheat responsible for scab resistance. Further analysis of the data will cover the metabolite interactions of the inflection process resulting in information that has not been reported before. Additional benefits could be the use of unique metabolites as biomarkers for scab screening in breeding.

Vacuum Steam Pasteurization and Wheat Quality

Vacuum steam pasteurization has shown promise on a research scale for the inactivation of E. coli and S. enterica on low moisture foods including grain (Shah et al. 2017). This control measure utilizes increased pressure in combination with moderate temperatures (as compared to other pasteurization methods) to inactivate pathogenic bacteria. Temperatures used for this control measure range from 60 to over 100 °C.

The main steps in this process include pre-heating (to facilitate homogenous treatment during pasteurization), pasteurization, and cooling (if needed) (Shah et al. 2017). The pasteurization process itself is divided into four steps: initial application of the vacuum to build pressure, pre-vacuum, pasteurization, and post vacuum. All steps in the process can be adjusted to suit the matrix of the material being pasteurized. One complete cycle of pasteurization typically takes between 20 and 25 minutes.

This method has proven effective at reducing the E. coli O157:H7 and S. enterica Enteritidis PT 30 loads on quinoa, flaxseed, and sunflower kernels (Shah et al. 2017). When pasteurized at 75 °C for one minute, 5.40 to 5.89 log reductions of E. coli O157:H7 were achieved for these crops. At these same processing conditions, 4.01 to 5.48 log reductions of S. enterica Enteritidis PT 30 were attained for these crops. Due to the proven effectiveness of vacuum steam pasteurization for the inactivation of E. coli O157:H7 and S. enterica Enteritidis PT 30 on other low moisture crops, it may prove effective for the inactivation of these bacterial pathogens on wheat.

Wheat Quality & Carbohydrate Research
Department of Plant Sciences
NDSU Dept. 7670
PO Box 6050
Fargo , ND 58108-6050
166 Loftsgard Hall
(701) 231-7737
Fax: (701) 231-8474
Site Manager: Senay Simsek
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