The Study On Regulation Mechanism In Wheat-psathyrostachys Huashanica Amphiploid And Its Mother Parent In Tolerance To Phosphate Starvation

Phosphorus starvation has a huge impact on the safety of agricultural production.It is important to study the physiological mechanism of wheat growth under phosphorus starvation.In this study,the amphiploid PHW-SA and its mother parent J-11 were used to uncover growth characteristics and physiological differences in order to reveals the tolerance mechanism of wheat amphiploid under phosphorus starvation by hydroponics,which provided scientific basis for the selection of high-efficiency phosphorus crops,and ensures the efficiency and safety of wheat production.The main results as follows:(1)The accumulation of biomass and the content of total phosphorus in leaves of PHW-SA and J-11 decreased under phosphorus starvation,but the decrease rate of PHW-SA was lower than that of J-11.In respect of root morphology,phosphorus starvation inhibited J-11 root surface area and root volume,while PHW-SA significantly increased under phosphorus starvation.The anatomical structure of root cells showed that phosphorus starvation increased the cortical thickness in PHW-SA and J-11,but inhibited the xylem size and reduced the secondary xylem number in J-11.The negative effects on xylem development in PHW-SA is not obvious.(2)Phosphorus starvation significantly inhibited the photosynthetic parameters of J-11,but no significant effects on PHW-SA.Under phosphorus starvation,the maximum photochemical quantum yield was significantly reduced in J-11,but no significant in PHW-SA.Phosphorus starvation induced the secretion of acid phosphatase in the roots.PHW-SA had stronger acid phosphatase secretion ability than did J-11,which promoted the absorption of phosphorus elements.(3)Transcriptome analysis revealed that 3836 differentially expressed genes were found between J-11 and PHW-SA under phosphorus starvation,and 7274 genes were differentially expressed between normal condition and phosphorus starvation in PHW-SA.The differentially expressed genes of J-11 and PHW-SA under phosphorus starvation were mainly enriched in tricarboxylic acid biosynthesis,nicotinamide metabolism,nicotinamide synthesis,nicotinamide synthase activity,and oxidoreductase activity on basis of GO function and enrichment analysis.In the glycerophospholipid metabolic pathway,glycerol lipid metabolic pathway and ABC membrane transporter pathway,the differentially expressed genes were obviously founde to enrich.Phosphorus starvation induced the overexpression of PLD1 and PLD2 of phospholipase D gene,which may be the main reason for the stronger phospholipid conversion ability.In PHW-SA,it was involved in phytohormone signal transduction being induced under phosphorus starvation.It was suggested that overexpression of the auxin signalling gene AUX1 and the mitogen signal gene CRE1 may be important factors for root structure development in PHW-SA under phosphorus starvation.Over expression of CTR1 in the ethylene signaling pathway may be an important factor of acid phosphatase activity enhancement under phosphorus starvation.