Date Published: June 1, 2018
Publisher: Public Library of Science
Author(s): Eleonora Boncompagni, Gregorio Orozco-Arroyo, Eleonora Cominelli, Prakash Irappa Gangashetty, Stefania Grando, Theophilus Tenutse Kwaku Zu, Maria Gloria Daminati, Erik Nielsen, Francesca Sparvoli, Khalil Kashkush.
Pearl millet [Pennisetum glaucum (L.) R. Br.] is an important “orphan” cereal and the most widely grown of all the millet species worldwide. It is also the sixth most important cereal in the world after wheat, rice, maize, barley, and sorghum, being largely grown and used in West Africa as well as in India and Pakistan. The present study was carried out in the frame of a program designed to increase benefits and reduce potential health problems deriving from the consumption of pearl millet. The specific goal was to provide a database of information on the variability existing in pearl millet germplasm as to the amounts of phytate, the most relevant antinutrient compound, and the goitrogenic compounds C-glycosylflavones (C-GFs) accumulated in the grain.Results we obtained clearly show that, as indicated by the range in values, a substantial variability subsists across the investigated pearl millet inbred lines as regards the grain level of phytic acid phosphate, while the amount of C-GFs shows a very high variation. Suitable potential parents to be used in breeding programs can be therefore chosen from the surveyed material in order to create new germplasm with increased nutritional quality and food safety. Moreover, we report novel molecular data showing which genes are more relevant for phytic acid biosynthesis in the seeds as well as a preliminary analysis of a pearl millet orthologous gene for C-GFs biosynthesis. These results open the way to dissect the genetic determinants controlling key seed nutritional phenotypes and to the characterization of their impact on grain nutritional value in pearl millet.
Pearl millet [Pennisetum glaucum (L.) R. Br.] is the sixth most important cereal in the world and is the most widely grown among all the millet species worldwide, followed by foxtail millet (Setaria italica), proso millet (Panicum miliaceum) and finger millet (Eleusine coracana) .
Pearl millet is a staple food for more than 90 million people in Africa and Asia, thus the nutritional quality of the grains has a big impact on the diet of these populations. Efforts to improve this crop are increasing (reviewed by [56–58]) and very recently the sequence of pearl millet genome was released , opening new opportunities for accelerating breeding of this species. With the purpose to contribute to the knowledge needed for breeding programs regarding nutritional traits of pearl millet, here we analysed the content of the major antinutrient phytic acid and of the goitrogenic C-glycosylflavones of the grain and provide information on genes involved in their biosynthesis. To our knowledge this is the first report in which the variability of these compounds was assessed in a large number of samples belonging to a panel of inbred lines covering a large genetic diversity.
The research described in the present paper was the first phase of a program designed to improve pearl millet—derived food by accomplishing the following objectives: 1) reduction of the level of phytic acid accumulated in the grain; 2) reduction of the potential health problems derived from the presence in the grain of the goitrogenic C-glycosylflavones.