Nutrition Spain , Salamanca, Thursday, April 16 of 2015, 14:56

Nitric oxide is vital for the germination of seeds

The Hispano-Portuguese Institute for Agricultural Research (Instituto Hispanoluso de Investigaciones Agrarias, CIALE) of the University of Salamanca is beginning to obtain results as part of a European project that aims to make better quality seeds availa

José Pichel Andrés/DICYT A team from the Hispano-Portuguese Institute for Agricultural Research (CIALE) of the University of Salamanca has confirmed that nitric oxide (NO), a molecule that regulates many plant processes, is vital for seed germination. The finding is part of an extensive project designed to improve seed quality in which researchers from several European countries are taking part.


“The aim is to get to know the impact of environmental conditions in seed processes”, the CIALE researcher Óscar Lorenzo explains to DiCYT. As factors such as drought, temperature, or the passage of time may influence seed germination or the vitality of the subsequent growth of the seedling, scientists therefore want to find out which molecules are related to all these aspects.


For the moment, the experts of the University of Salamanca have obtained their first results with the plant Arabidopsis thaliana, which is a model for plant research, but the idea is to apply this knowledge to crops of interest to farmers, such as tomatoes, sunflowers, or barley on which their European colleagues are already working.


In previous studies the Group of Physiology and Hormonal Signalling in Plants of the CIALE had analysed transcription factors, which are regulating proteins that are vital for plant growth. However, they have now identified two that are directly related to essential seed processes: germination and the accumulation of fatty acid reserves. Experiments have shown that both depend on nitric oxide, a gas that has extremely important functions in all living creatures.


In the first case, “nitric oxide modifies a specific amino acid and this change favours the degradation of the transcription factor that maintains the dormancy of the seed, allowing it to germinate”. This process is essential because the seeds have to germinate at the right moment for the plant to be viable; this time is generally related to the season of the year, regardless of whether the environmental conditions such as temperature or humidity are suitable.


In the second case, nitric oxide plays a vital role in the accumulation of fatty acids such as oleic or linoleic acid by the seed. These reserves "feed” the new seedling when it begins to develop. Moreover, the process is very important to man because it gives great nutritional value to edible seeds such as vegetables.


As well as carrying out many functions in both plants and animals, nitric oxide is a greenhouse gas, which means that part of the research also involves confirming the consequences it may have on the biology of the seed if its concentration in the atmosphere continues to increase.


Guaranteeing viable crops


In any case the main aim of the project is the analysis of all keys so that seed distribution companies can offer an improved product and “that the farmer knows that 100% of the seeds will germinate and that 100% of the seedlings generated will be viable and healthy”. To achieve this, scientists are analysing each variety from a genetic and molecular point of view and are studying the functions of each molecule and how they will respond to hypothetic stress situations, such as those that in theory will be caused by climatic change with droughts or increased temperatures.


Óscar Lorenzo's team, with the addition of Isabel Mateos and Inmaculada Sánchez, has been working on this project for two years. This research is entitled EcoSeed-Impacts of Environmental Conditions on Seed Quality and is part of the European Knowledge Based Bio-Economy (KBBE) programme which will continue until late 2016 with the participation of France, the United Kingdom, Germany, and Austria. The CIALE is the only Spanish representative.


As well as achieving these results with the model plant, the Salamanca researchers are receiving seeds of plants of agricultural interest such as sunflowers or soya that have already been treated by other members of the project, for instance by ageing processes, in order to identify molecular components and see how they behave.