Abstract
BackgroundMethyl Jasmonate (MeJA) could promote the opening of sorghum florets, but the molecular mechanism remains unclear.ObjectiveWe aimed to investigate the molecular mechanism of exogenous MeJA in promoting the opening of sorghum florets.MethodsHybrid sorghum Aikang-8 was selected as the test material in this study. Sorghum plants of uniform growth with approximately 20%-25% florets open were selected and treated with 0, 0.5 and 2.0 mmol/L of MeJA. Totally there were 27 samples with lodicules removed were obtained at different time points and used for the transcriptome analysis using the BGISEQ_500RS platform.ResultsThe results showed the sorghum florets opened earlier than the control after the treatment with exogenous MeJA, and the promotive effect increased along with the increase of exogenous MeJA concentration. The number of differentially expressed genes (DEGs) in plasma cells increased with the increase of MeJA concentration, whether up- or down-regulated, after the exogenous MeJA treatment. Besides, the number of metabolic pathways was also positively correlated with the concentration of MeJA. GO and KEGG analysis suggested the DEGs were mainly enriched in starch and sucrose metabolism-related pathways (i.e., LOC8063704, LOC8083539 and LOC8056206), plant hormone signal transduction pathways (i.e., LOC8084842, LOC8072010, and LOC8057408), energy metabolic pathway (i.e., LOC8076139) and the α-linolenic acid metabolic pathway (i.e., LOC8055636, LOC8057399, LOC8063048 and LOC110430730). Functional analysis of target genes showed that two genes named LOC-1 (LOC8063704) and LOC-2 (LOC8076139) could induce the earlier flowering of Arabidopsis thaliana.ConclusionThe results of this study suggest that exogenous MeJA treatments could induce the up- or down- regulation of genes related to starch and sucrose metabolism, -linolenic acid metabolism and plant hormone signal transduction pathways in the plasma cells of sorghum florets, thereby promoting the opening of sorghum florets.
Highlights
In northern regions of China, sorghum was widely planted as a major food crop as well as other important resources for forage, food and brewing industries
The results showed the sorghum florets opened earlier than the control after the treatment with exogenous Methyl Jasmonate (MeJA), and the promotive effect increased along with the increase of exogenous MeJA concentration
The number of differentially expressed genes (DEGs) in plasma cells increased with the increase of MeJA concentration, whether up- or down-regulated, after the exogenous MeJA treatment
Summary
In northern regions of China, sorghum was widely planted as a major food crop as well as other important resources for forage, food and brewing industries. There are many documents on the regulation of spikelets opening influenced by external environment factors, resembling light, temperature, CO2 and mechanical stimulation, but the research about the spikelets opening regulated by endogenous signal molecules were still unknown [2,3,4]. Floret opening in grass plants is mainly caused by the swelling of a pair of lodicules at the base of the floret after water absorption [5] In this process, the lodicules first swell and push chaff outward and palet inward, leading to the separation of chaff and palet, florets open [6]. Methyl Jasmonate (MeJA) could promote the opening of sorghum florets, but the molecular mechanism remains unclear
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
