**6. Discussion**

In order to explain the possible shortage of food globally, Malthus [1] warned about overpopulation. He did not take into consideration the fact that more food required could be produced due to scientific and technological development. The forecasted mass starvation has so far not become a reality. Diamond [5] blamed consumption, especially overconsumption in the developed world. The present global food production is not sustainable and accompanied by huge losses and wastes along the value chain. For this reason, agricultural production needs a reorganization with specific local solutions for particular regions.

Half of total losses occur before the process of harvesting begins representing 1051.5 mt annually. This makes production per unit more expensive. Among the causes of crop losses, the bottleneck e ffect between basic, applied research, and breeding must be highlighted, which means that most of the

available existing knowledge does not reach, for example, those involved in breeding, plant protection, agronomy, etc. Consequently, the effectiveness of the combination and utilization of the knowledge adapted for local and regional breeding, agronomy, etc. is very poor and the results are embarrassing. More knowledge is needed about the interrelations between disease resistance, yield ability, and the efficacy of pesticides and agronomy responses at cultivar level to develop the optimum mix of different procedures for each region and field. At least two third of grain field losses, namely 700 mt, are related to biotic stresses. Plant breeding is supposed to be responsible for about a third of this amount (233 mt). However, it is impossible to breed for resistance against 200 diseases of a crop. Plants are generally treated for the 4–5 most important diseases by farms; therefore, resistance and pesticide treatments should be combined. For the rest of the losses (roughly 500 mt) correct pest managemen<sup>t</sup> and agronomy measures combined are needed. Suggestions made by Lamichhane et al. [66] for organic culture are also necessary for conventional plant production. Near Szeged (southern Hungary), Mesterházy et al. [64] and Mesterházy et al. [65] reorganized the crop structure and fungicide program and tillage for wheat. Without any additional cost, the wheat yield became much healthier (fewer toxins and leaf diseases), and a 4–5% yield increase could be achieved on about 2000 ha of wheat.

Grain production is expected to expand well below the growth rates of the last decades. Yield increase will not be sufficient to achieve global food security. The potential increase in maize, wheat, rice and soybean yields will be less than 10% in the next five years, resulting at the most in 220 million mt of extra yields. Comparing the projected extra yields of grains for the next five years, with the annual losses and waste of about 980 mt excluding pre-harvest losses, it becomes apparent that reducing food loss and waste can help to enhance food security more efficiently then yield increase can. The slowdown in global annual yield growth is the main challenge facing global food security. Maize, rice, wheat, and soybean together produce about 64% of global agricultural calories (of this maize, rice, and wheat 57%) and decreasing yield gains in these crops will have serious implications for the global grain supply chain [85]. Grain yields are affected by both biophysical and socioeconomic factors worldwide leading to increased yield variability in the future. Climate-change-related heat stress, scarcity of water for irrigation, depletion of soil fertility and salinization, soil erosion, pest and disease build-up and a lack of capital will have a greater impact on yield development than the genetic improvement of grain cultivars. In Europe, yields are affected by climate change in several EU member states.

Moreover, agricultural subsidies are tied to the reduction of environmental burden and agricultural inputs, leading to yield stagnation. For this reason, the reduction of loss and waste is the most important factor in achieving food security with a much larger impact on the grain supply for food and feed than higher yielding crops. Breeding for yield stability and resistance combined with advanced pest managemen<sup>t</sup> strategies, improved agronomy and storage could reduce grain losses and waste by at least 50% and meet the demand for grain for an additional 3-4 billion people globally.

At least two third of the field losses namely 700 mt are related to biotic stresses. Plant breeding is supposed to be responsible for about a third of this amount (233 mt). However, it is impossible to breed for resistance against 200 diseases of a crop. Plants are generally treated for the 4–5 most important diseases by farms; therefore, resistance and pesticide treatments should be combined. For the rest of the losses (roughly 500 mt), both correct pest managemen<sup>t</sup> and agronomy measures are needed.
