Differential Proteomics Analysis On The Germination Of Wheat Hybrids Created By Chemical Hybridizing Agent

The utilization of heterosis is one of the main ways to improve crop yield.The suitable hybrid combinations of wheat show great potentiality in the main agronomic characters.Using chemical male sterility to induce male sterility to prepare wheat hybrids,great progress has been made in wheat.However,chemical hybrids may have adverse effects on the development and germination of hybrids,especially at the stage of seed development.In this study,the male parent Shannong 22 of female parent RS53,and the hybrid grain of wheat produced with chemical killing agent SC2011 were used as experimental materials.The germination ability of wheat seeds was determined by conventional method,and the iTRAQ method was used to analyze the relationship between hybrids and their parents.The differential proteins of seed germin ation were analyzed by bioinformatics.In this study,the germination characteristics,germination mechanism and differential proteins of hybrid seeds were analyzed in order to provide the theoretical basis for the development of low toxicity chemical male killing agents,the allocation of suitable wheat hybrid combinations,and the optimization of germination characters of wheat hybrids.It has practical application value to promote the advantage utilization of wheat hybrids.The main results are as follows:1.The germination characteristics of hybrid seeds were as follows: the root length and bud length of hybrid seeds were significantly slower than that of their parents;the germination energy,germination percentage,germination index and vigor index of hybrid seeds were lower than those of male parent Shannong 22 and female parent RS53;and the germination rate,germination index and vigor index were lower than those of male parent Shannong 22 and female parent RS53.The application of fungicide to the female parent RS53 may affect the seed development of the hybrid and lead to the low viability of the hybrid seed germination.2.Proteomics studies based on iTRAQ showed that there were 1631 differentially expressed proteins between hybrids and their parents at germination stage.Compared with the maternal parent RS53,377 proteins were up-regulated,including 212 functional proteins,338 down-regulated proteins and 210 functional known proteins.Compared with the male parent SN22,there were 481 up-regulated proteins,273 functional known proteins,435 down-regulated proteins and 285 functional known proteins in hybrids.3.By bioinformatics analysis,the results of GO annotation showed that there were 78 and 48 GO entries,25 and 12 molecular functions,and 33 and 32 cell components,respectively,in biological processes,which were different from male and female parents.Among them,the common GO entry with male parent and female parent is the reaction to stimulation,the reaction to abiotic stimulation,the reaction to inorganic substance,etc.,in the cell composition,it is the organelle part,the periphery of cell,the plasma membrane,and so on,in the process of biology,the reaction to abiotic stimulation,the reaction to inorganic substance,and so on.In molecular function,lyase activity,transferase activity,nucleic acid binding and so on.4.Pathway analysis of differentially expressed proteins showed that 94 pathways were obtained from the differentially expressed proteins between hybrid and male parent SN22,mainly concentrated in metabolic pathway,ribosome,endoplasmic reticulum protein processing,starch and sucrose metabolism,and so on.A total of101 pathways were obtained from the differentially expressed proteins between hybrid and maternal RS53,mainly focused on metabolic pathway,ribosome,oxidative phosphorylation,endoplasmic reticulum protein processing,glycolysis,and RNA transport.There are 26 differential proteins clustered in ribosomes,which are distributed in several ribosomal active sites such as IF1,EF-Tu,EF-Ts,A.7 differential proteins clustered in proteasome.There were 11 differential proteins in starch and sucrose metabolic pathway.Ribosomal protein was disordered in the assembly of wheat hybrids prepared by the chemical killing of wheat(Triticum aestivum L.).The expression of related enzymes in starch and sucrose metabolism pathway was down-regulated,and the energy supply of hybrid was insufficient during germination,which led to the lower germination ability of hybrid compared with its parents.The chemical killing agent caused damage to hybrid and upregulated the expression of proteasome-related protein,which might have repair effect on hybrid.