**7. Conclusions**

Increasing global population and decreasing natural resources associated with growing FL and FW have resulted in an unprecedented challenge. Transforming a wasteful food supply chain into a sustainable food solution needs collaboration between researchers and multi-stakeholders in the food supply system. This conclusion is in line with several studies [16,19,29,30]. We have to understand the key drivers causing FL and FW across the food supply chain and find solutions for reducing these losses and waste. The field of FL and FW lacks appropriate metrics used to calculate benefits and trade-offs. Stakeholders in the food supply chain have incomplete data about how much FL and FW is generated or the total costs of its managemen<sup>t</sup> to make these comparisons. This outcome is supported by other reviews as well [9,10].

The results show that cumulating harvesting, storage and toxins losses along the grain supply chain may reach up to 690 mt annually, excluding the 1.051 mt of pre-harvest losses. Besides pre-harvest losses, the highest rates of loss are associated with storage and mycotoxin contamination. Breeding, cultivation, plant protection, harvesting, storage, handling, and transportation practices play key roles in the e fficiency of the grain supply chain. Grain loss in the future depends on technology and the workforce. In addition, consumer waste is based on consumer behavior and food waste management.

At present, a significant increase in global grain production only by the introduction of new higher yielding varieties is not possible. What are the limitations? Interestingly, it is not the shortage of inputs, such as fertilizers, chemicals, etc., that plays an important role in restricting increases in the yield and quality of cereals. The shortage of water is an acute problem on one side, with research on the other. Cooperation among those involved in breeding to increase yield, to improve resistance to biotic and abiotic stresses and agronomy is poor, as these fields largely work separately from each other and their positive innovative e ffects are not utilized to the extent that could be possible. Special problems occur in the field of toxigenic fungi. However, in recent decades screening and genetic methods have been used to increase resistance levels. The problems at the harvest and storage stages represent a very strong limitation, leading to losses of several hundred million tons of grains. In many regions of the globe poor infrastructure is also a strong limiting factor, inhibiting the application of modern logistics, installations, machines etc. The lack of special education is a very strong limiting factor causing very high losses before and after harvest. This conclusion is consistent with previous studies [24,29,30].

How do we prevent a significantly higher amount of loss? Plant breeding must consider closely global needs and local activity in order to reach the highest adaptation of the cultivars bred, because cultivars have to resist to di fferent challenges of both biotic and abiotic stresses. We face a special problem in stresses such as drought, heat, toxic fungi, and leaf spots that inherit mostly polygenic traits and so breeding is more complicated than in the case of monogenic traits. We should be aware that each crop has about 200 pathogens, of which 4-5 can be treated in a breeding program, indicating the need for chemical control when a new disease appears in the field. A much higher resistance is needed against toxigenic fungi; therefore, crop production must be much better adapted to local conditions. The finding is in line with previous literature [28].

About 20 years ago, we spoke about integrated crop managemen<sup>t</sup> to reduce pesticide use. Today, Intelligent Field Crop Management is spreading. It is necessary to evaluate for each field the optimal mix of variety, agronomy, pesticide application, irrigation, and previous crop selection to ensure maximum possible yield by using necessary pesticides. Harvest and storage managemen<sup>t</sup> should be modernized. The current best available technologies reduce loss during storage by 2–3% without quality reduction. This outcome is in accordance with the studies published by [8,19,34,35].

In order to prevent grain loss farmers should be educated globally; the extension service in the US can be an example to follow. Demonstration farms can show farmers how intelligent field crop managemen<sup>t</sup> works in practice. The vocational school system should also be adopted to meet these new challenges. The production method used in developed countries should also be applied in the developing world. Developed countries also face new problems, including the ecological crisis, therefore new solutions are needed through global action and scientific innovation. Local agricultural development programs can solve local problems, but international organizations must support and harmonize the global and local network.

Agriculture is a capital and knowledge-intensive sector, so huge agricultural investments must be made in the next few decades to meet the challenges of the growing yield demand for grain, and at the same time to maintain a sustainable environment. Therefore, reducing global losses and waste along the grain supply chain is the most e ffective way to increase global food and nutrition security. This needs long term thinking and not short run profit at a maximum level. For this reason, national

and global regulations, investment and scientific policies are preconditions to provide reasonable and sustainable solutions for the future; however, the largest task is to change the way we think.

**Author Contributions:** Á.M. and J.P. conceived and designed the experiments. Á.M. and J.P. contributed analysis tools. Á.M., J.O. and J.P. wrote the paper. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Acknowledgments:** The authors are indebted to the projects MycoRed FP7 (KBBE-2007-2-5-05 (2009–2012), GOP 1.1.1.-11-2012-0159 EU-HU (2012–2013), GINOP-2.2.1-15-2016-00021 (2016–2020) and TUDFO/5157/2019/ITM for financial support. This research was supported by the ÚNKP-19-4-DE-147 New National Excellence Program of the Ministry for Innovation and Technology and by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences.

**Conflicts of Interest:** Authors declare that there is no conflict of interest.
