Effect of ultrasonic seed treatment on rice seedlings under waterlogging stress

Abstract

One of the main problems of rice (Oryza sativa L.) cultivation is erratic germination and crop establishment; therefore, a pre-sowing ultrasonic seed treatment was studied to improve this situation. A pot experiment was conducted to investigate the effect of ultrasonic seed treatment on rice seedlings under waterlogging conditions. Two cultivars of rice seeds, 'Yuejingsimiao' (YJSM) and 'Yuxiangyouzhan' (YXYZ), were treated with ultrasonic waves before being transferred to the pot. The ultrasonic treatment included seed treatments in the dry state (S1), wet state (S2), and a control (CK). The waterlogging treatment included three flooding levels, control (W0), 2.0-3.0 cm flooding (W1), and 3.0-4.0 cm flooding (W2). The seedling emergence rate for W1S2 was 35.07% to 64.39% higher than W1CK, while fresh weight for W2S2 increased by 54.21% to 89.98% compared with W2CK. Furthermore, W1S1 (11.74% to 15.02%) and W1S2 (7.87% to 43.29%) also increased catalase activities compared with W1CK. Malondialdehyde (MDA) decreased by 19.87% to 31.84% and 9.70% to 38.74% for YJSM and YXYZ, respectively. The results showed that under waterlogging conditions, wet seed under ultrasonic treatment significantly increased the seedling emergence rate. Both the wet and dry seed treatments improved seedling quality, antioxidant activity, but decreased the MDA content.

Seed germination and seedling development assisted by ultrasound: gaps and future research directions

“… 97,100,101 Different studies have demonstrated beneficial effects of ultrasound treatment on seedling development of different species ( Table 4 ) including, inter alia , sunflower, 94 switchgrass, 65 pea, 29 alfalfa, 30 senna multijuga 96 . Ultrasound treatment (20 kHz and 220 W) of seeds from two rice cultivars, demonstrated positive effects on seedling total leaf area, basal seedling diameter, the number of total roots, seedling emergence rate and fresh and dry weight 62 . In the same species, an ultrasound treatment of 25 kHz and 16 WL −1 for 5 min increased sprout development speed 75 .…”

“…Abiotic stressors (temperature, drought and radiation) elicit the plant defense mechanism through the activation of enzymatic defense systems, including peroxidase and catalase, which protect the plasma membrane against lipid peroxidation 88,89 . Different studies have shown that ultrasound treatment inactivates lipoxygenase and stimulates catalase, peroxidase and superoxide dismutase activity, thus decreasing malondialdehyde levels (the final product of polyunsaturated fatty acids peroxidation) and the superoxide radical (O2•−), promoting the regeneration of membrane integrity 17,62,90,91 . In addition, ultrasound treatment has been shown to increase total polyphenols, total flavonoids, and total saponin content and further enhanced the antioxidant activities (ferric reducing antioxidant power ‐ FRAP; 2,2‐Diphenyl‐1‐picrylhydrazyl ‐ DPPH) of the produced sprouts 45 .…”

Effects of submergence stress at the vegetative growth stage on hybrid rice growth and grain yield in China

“…However, the frequent heavy rainfall events occurring from May to June often floods rice fields in the lowland areas when rice plants are at the vegetative growth stage (Hao, 2012). Floods occurring at this stage negatively affects rice growth and grain yield by reducing numbers of tillers, plant leaf area and dry weight above ground, and in the worst case, by causing high mortality (Ella et al, 2011;Kato et al, 2014;Huang et al, 2020). A previous study showed that in China more than four million hectares of rice fields are prone to flooding and the submergence caused yield losses of more than one million tons every year (Chen et al, 2005).…”

Analysis of the effect of ultrasound on Hymenaea courbaril L. seeds / Análise do efeito do ultrassom em sementes de Hymenaea courbaril L.

“…The waves impose a mechanical pressure on the cell wall of the seed increasing its porosity and allowing permeability to the entry of oxygen and water ETEGHADIPOUR, 2017). This fact stimulates cells to increase their Brazilian Journal of Development, Curitiba, v.7, n.11, p. 105910-105921 nov. 2021 enzymatic activities and change their structure to soften the seed coat and absorb nutrients (HUANG et al, 2020).…”