The flux rate of Ca2+ into embryo can be used to evaluate the vigour level of maize seeds

Abstract

Seed vigour is an important trait and is often used to evaluate seed quality. A rapid and accurate evaluation of seed vigour is very important for agricultural production. Ca 2+ is an important secondary messenger in plants, responding to various biotic and abiotic stimuli by Ca 2+ flux into cytoplasm. To the best of our knowledge, however, no report has been published about seed vigour and Ca 2+ influx. In this study, we used two hybrid maize (Zea mays L.) lines and their corresponding female parent lines as materials, and performed ageing and 'ageing + priming' treatments to obtain seeds with different vigour levels. After seeds were imbibed for 24 h, the intact seeds or embryos were used as materials for determining the Ca 2+ influx rate using non-invasive micro-test technique (NMT). Results showed that, with the intact embryos as materials, the Ca 2+ influx rate showed higher stability and higher values. Correlation analysis indicated that there was a significant, positive linear correlation between the shoot dry weight vigour index and Ca 2+ flux rate into embryo. The results demonstrated that the Ca 2+ influx rate can be used to evaluate the vigour levels of maize seeds.

High-Vigor Maize Seeds Resist Fusarium graminearum Infection through Stronger Ca2+ Signaling

“…Singh et al [6] and Verma et al [34] demonstrated that the Ca 2+ required for the early germination of mung bean (Vigna radiata) seeds came from the apoplastic calcium store. Our previous study showed that during the imbibition of maize seeds, Ca 2+ in embryo cells flowed from the extracellular calcium pool into cells, and the influx rate of Ca 2+ in the embryos of high-vigor seeds was higher than that of low-vigor seeds [29]. In the present study, although the treatments with all the three inhibitors significantly inhibited seed germination and seedling growth, in the presence of F. graminearum infection, the vacuolar Ca 2+ channel inhibitor RR showed the highest inhibitory effect (Figures 5 and 6), while in the absence of F. graminearum infection, the inhibitor LaCl 3 showed the highest inhibitory effect (Figure 7).…”

“…In a previous study, the flow rate of Ca 2+ flowing from the extracellular matrix to the embryo cells showed a significant positive correlation with maize seed vigor during imbibition [29]. To determine how the vigor of maize seeds affected their resistance to F. graminearum, we transformed maize with the expression vector pBIN-YA (B) and obtained transgenic plants expressing the YFP-aequorin gene [25].…”

Transcriptome analysis of Gossypium reveals the molecular mechanisms of Ca2+ signaling pathway on arsenic tolerance induced by arbuscular mycorrhizal fungi

“…In plants, Ca 2+ ions serve as a crucial secondary messenger responding to various environmental stimuli, such as heat, salt, cold, drought, and heavy metal stresses ( Sanders et al, 1999 ). Under abiotic stress conditions, plants release Ca 2+ from both extracellular and intracellular sources into cytoplasm through Ca 2+ channels, leading to a rapid increase in cytosolic-free Ca 2+ concentration ( Zhu et al, 2020 ). Ca 2+ fluxes play a pivotal role in the early defense responses of plants, exhibiting complex spatiotemporal patterns ( Kurusu et al, 2010 ).…”

“…Ca 2+ fluxes play a pivotal role in the early defense responses of plants, exhibiting complex spatiotemporal patterns ( Kurusu et al, 2010 ). Positive values of Ca 2+ fluxes indicate an outflow, while negative values suggested an inflow ( Zhu et al, 2020 ). In this study, the Ca 2+ fluxes in Gossypium leaves and roots were investigated by using non-invasive micro-test technique; As stress increased the net fluxes of Ca 2+ in both leaves and roots under the same inoculation condition.…”