The United Nations has set 17 goals for global sustainable development. Number two is the goal of zero hunger by 2030. To achieve this, agricultural production must be doubled, but some studies suggest that yield development will not be sufficient to reach this goal. One of the reasons for this is climate change. Moreover, heat waves, heavy rainfall and rising sea levels are predicted for the 21st century, with drought, floods and salinisation among the most critical consequences for food production. Today, abiotic plant stress is the main cause of severe yield losses of 50-80%, depending on the crop and geographical location. This is a major problem that needs to be solved in the coming years. This daunting situation is an excellent opportunity for plant scientists to apply their knowledge in an interdisciplinary way in agriculture to increase productivity under abiotic stress. In this regard, BS encompass a plethora of disciplines including chemistry, biochemistry, plant physiology, genetics and agronomy, which make for an interesting field of study. Biostimulants (BS) are extensively studied in plant science research. It is emphasised that they are an environmentally friendly way to manage biotic and abiotic stresses and increase food production, and their mode of action is being studied in depth.
A biostimulant (BS) is any compound, microorganism or mixture thereof, with the exception of fertilisers and pesticides. Biostimulants are usually environmentally friendly and inert to ecosystems. Their use is frequently reported in the literature to increase stress tolerance or to increase yield in the field2. In terms of plant health, BS are a good alternative to achieve the annual EU targets announced in the Communication: "A farm-to-table strategy for a fair, healthy and environmentally friendly food system". A good example of this way of thinking is the research carried out by the experienced researcher of this proposal. The use of L-pyroglutamic acid can save 30% of the water requirement and produce higher yields. However, to be effective, weekly treatments of 500 g per hectare are required. This means an additional cost of €20 per hectare per week to reduce irrigation by 30%, with some yield losses. One of the main reasons is probably the easy degradability of BS. Indeed, the application of pure bioactive compounds is also very limited due to their rapid release, low solubility and poor bioavailability5. An alternative to counteract these drawbacks is nanocapsulation. The present proposal is a novel interdisciplinary approach that aims to multiply the efficacy of BS by constructing a nanostimulant (nanoparticles encapsulating a BS ). It updates the traditional BS applications in this field by using the most advanced techniques of nanocapsulation (NE).
