## 4 Plasma Technology for Crop Sustainability and Food Processing  
Sustainable crop production and food security are important issues for modern society. Therefore, the development of technologies to address these issues is urgently needed. Sustainable agriculture technologies can not only increase crop production and tolerance but also help to preserve natural resources and ecosystems. Cold atmospheric or low pressure plasma is a modern-age technique that may alleviate the risks associated with agriculture and food processing systems. Cold atmospheric or low pressure plasma is an eco-friendly approach that positively affects crop production under adverse conditions. Various biotic and abiotic factors affect crop production, and several old agrochemical and biotechnological approaches have been used to address these issues. However, they often have negative impacts on the ecosystem. Plasma represents a risk-free approach because it requires low energy, is waste-free, and has no negative effects on the environment. The effects of cold atmospheric or low pressure plasma treatment on seed germination and seedling growth under drought, salt, and chemical toxicity have been currently more studied (Table 3). Figure 2: Effects of plasma-generated reactive oxygen and nitrogen species (RONS) in different plant organs at different growth stages. Direct and indirect exposure to plasma induces RONS in various plant organs (shoots, roots, leaves, and flowers) and activates different signaling cascades that crosstalk with other small signaling molecules and hormones to affect growth, development, and immunity. BR: Brassinosteroid, ABA: Abscisic acid, SA: Salicylic acid, JA: Jasmonic acid, MAPK: Mitogen activated protein kinase, WUS: WUSCHEL. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  
Several studies have shown improved tolerance to abiotic stress after plasma treatment. [PERSON] et al. [84] treated the seeds of two _Brassica napus_ cultivars (Zhongshuang 7, a drought-sensitive cultivar, and Zhongshuang 11, a drought-resistant cultivar) with helium plasma and found that plasma treatment enhanced seed germination under 15% (_w/v_) PEG 6000-mediated drought conditions. Similarly, the seeds of two _Arabidopsis_ mutants, _gl2_ and _gpat5_, were exposed to DBD air plasma, and he seed germination efficiency was assessed under salt stress. Plasma causes structural changes to the mantle layers of the seed coat, which reduces permeability and diminishes the effects of salt stress on seed germination [90]. Upregulation of the drought stress-regulating transcription factor (WRKY) and secondary metabolites in plasma-treated seedlings was reported by [PERSON] et al. [106]. More recently, [PERSON] et al. [93] demonstrated that cold atmospheric pressure plasma seed priming induces drought stress tolerance in seedlings--improved growth and biochemical alterations were observed in the cold plasma-primed tomato seedlings under 30% PEG-mediated drought stress. Other reports have shown that the plasma-activated water irrigation of barley improves hypoxia and low-temperature stress tolerance [92]. Pollutant soil contamination is a major concern in agriculture; the Air/Ar cold low pressure plasma treatment of wheat seeds reduced the accumulation of Cd during germination. This is because plasma treatment modifies the seed coat and reduces the pH of wheat seeds, resulting in Cd detoxification [91]. Plasma can promote plant tolerance to biotic stressors, such as pathogens and pests. Pathogenic diseases severely damage crop yield and are a major threat to food security. Cold low pressure plasma treatment of tomato seeds reduced bacterial wilt disease (causal agent: _Ralstonia solanacearum_) at the early vegetative stage [85]. Seed-borne pathogens, such as _Fusarium fujikuroi_ (Bakanae disease) and _Burkholderia plantarii_ (bacterial blight), can also be controlled by cold atmospheric pressure plasma irradiation on rice [107].