Cold Atmospheric Pressure Plasma Treatment of Maize Grains—Induction of Growth, Enzyme Activities and Heat Shock Proteins

Abstract

Zea mays L. is one of the most produced crops, and there are still parts of the world where maize is the basic staple food. To improve agriculture, mankind always looks for new, better methods of growing crops, especially in the current changing climatic conditions. Cold atmospheric pressure plasma (CAPP) has already showed its potential to enhance the culturing of crops, but it still needs more research for safe implementation into agriculture. In this work, it was shown that short CAPP treatment of maize grains had a positive effect on the vitality of grains and young seedlings, which may be connected to stimulation of antioxidant and lytic enzyme activities by short CAPP treatment. However, the prolonged treatment had a negative impact on the germination, growth, and production indexes. CAPP treatment caused the increased expression of genes for heat shock proteins HSP101 and HSP70 in the first two days after sowing. Using comet assay it was observed that shorter treatment times (30–120 s) did not cause DNA damage. Surface diagnostics of plasma-treated grains showed that plasma increases the hydrophilicity of the surface but does not damage the chemical bonds on the surface.

Biochemical and Physiological Plant Processes Affected by Seed Treatment with Non-Thermal Plasma

“…It has been proposed that NTP treatment accelerates ABA accumulation in the early growth stages and ABA regulates ROS and Ca 2+ concentrations to affect the stomatal aperture, which is associated with NTP-induced stimulation of seedling growth. Holubova et al [ 168 ] proposed that the accumulation of the heat shock protein HSP101 and HSP70 encoding gene transcripts is stimulated at the early stage (24 h) of maize seed germination due to the increased demand for the chaperones required to recover the cell proteins damaged by the NTP-treatment. Up-regulation of enzymes involved in the regulation of the cell redox balance, such as catalase (CAT) and superoxide dismutase (SOD), was observed in the roots of wheat seedlings [ 175 ] or the leaves of sunflower seedlings grown from NTP-treated seeds [ 169 ].…”

Understanding and Comprehensive Evaluation of Cold Resistance in the Seedlings of Multiple Maize Genotypes

“…Generally, tropical and subtropical maize are sensitive to cold stress [ 1 ]; therefore, maize that resists cold spells in early spring could broaden planting areas in high latitude regions, allow crop rotation, and increase yield by extending the growing season [ 24 ]. Moreover, the studies of different crops have shown that cold resistance is a complex biological process that involves interactions between agronomic traits and physiological processes and is dependent on the level of cold severity and timing in relation to the stage of crop development [ 7 , 25 , 26 , 27 ]. Therefore, it is vital for maize breeding programs to understand the physiological changes during seed germination and seedling development under low-temperature stress.…”

“…However, plants have antioxidant enzymes to counteract the effect of ROS; the increase of SOD, POD, CAT, and APX activities could scavenge excessive ROS [ 4 , 7 ]. Increasing evidence has shown that low temperature induced activation of antioxidant enzyme activities in Nicotiana tabacum L. and Secale cereale L. [ 37 ].…”

“…Cold temperatures also affected the abundance of carotenoids, which enhanced photoprotection by promoting the dissipation of excitation energy [ 3 ]. In addition, maize seedlings evolved an efficient antioxidant system including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), glutathione peroxidase (GPX), and ascorbate peroxidase (APX) to prevent extremely ROS accumulation under low-temperature stress [ 4 , 7 ]. Consequently, enhanced levels of different antioxidant gene transcripts have been found in maize as a potential low-temperature stress defense strategy.…”

Effects for barley growth and development of single exposure to low-temperature argon plasma at different organogenesis stages

“…Одним из наиболее вероятных практических применений низкотемпературной плазмы в агротехнологиях является предпосевная обработка семенного материала с целью обеззараживания их поверхности от микроорганизмов, а также для стимулирования прорастания семян, роста и развития растений [5]. В литературе приведены данные исследований обработки низкотемпературной плазмой для дезинфекции поверхностей различных семян: семян ячменя [6], сои [7], томатов [8], огурца и перца [9]; зерен кукурузы [10], семян маша, или бобов мунг [11], семян базилика [12].…”