Identification Of AsSPL Gene Family Members In The Oat Genome And Analysis Of Their Expression Patterns At The Tillering Stage In Naked Oat

SPL(SQUAMOSA PROMOTER BINDING PROTEIN-LIKE)is a class of transcription factors unique to green plants.Family members all contain conserved SBP domains,which are mainly involved in plant growth,flowering,biotic and abiotic stresses and other physiological processes.In recent years,studies have found that the SPL family is also involved in the physiological processes of various plants such as photoperiodic pathways,stress resistance and plant type construction,thereby affecting plant yield.Naked oat(Avena nuda)is the main cultivated oat species in China.The chromosome group is 2n = 6x = 42,AACCDD.As a cash crop for both food and feed,its tillering directly affects grain yield.At present,there is still a lack of systematic research on related genes in oat.In this study,naked oat was used as the main research object.Through the investigation and analysis of 205 naked oat core germplasm materials with physiological traits such as tillering at the whole growth stage,three oat materials with significant differences in effective tillering number were initially screened out,which were HX79,HX86 and HX91.At the same time,through genome-wide and transcriptome screening and analysis of the As SPL family,the expression patterns of some As SPL genes in the above three materials at the tillering stage were analyzed in multiple tissue sites,in order to provide useful information for oat breeding and improvement of oat yield.The main results of this study are as follows:(1)There were significant differences in agronomic traits(plant height,number of main stems and leaves,total number of tillers,effective number of tillers and total number of grains per ear)in 205 naked oat core germplasm materials during the two years(p < 0.001),but the overall trend was relatively stable;(2)The effective tillering rates of HX79 for two consecutive years were 60% and98.28%,respectively,and the effective tillering number was higher,which was a material with high effective tillering number;the effective tillering rates of HX91 for two consecutive years were 2% and 100%,respectively,and the effective tillering rate changed greatly,which was a material with medium effective tillering number;while the effective tillering rates of HX86 for two years were 0% and 58.57%,respectively,and the effective tillering number was less,which was a material with low effective tillering number;(3)Referring to the published oat genome database,a total of 28 As SPL genes were screened,named As SPL001-As SPL028,and distributed on each subchromosome group;all As SPL proteins were located in the nucleus;the gene structure,motif distribution and function of the same subfamily of As SPLs,and the distribution of cis-acting elements were basically similar;the isoelectric points and relative molecular weights of each As SPL protein were significantly different.(4)The CDS sequences of six genes As SPL8,As SPL15,As SPL010,As SPL017,As SPL021 and As SPL028 were obtained by co-cloning.(5)The expression of As SPLs gene at the tillering stage has obvious material specificity,which is related to the difference in its effective tiller number.As SPL028 was highly expressed in the stems and tillering nodes of the low-effective tillering material HX86,but low or no expression in HX79 and HX91;As SPL15 was highly expressed in the tillering nodes of the three materials at the four-leaf and five-leaf stages;As SPL017 was highly expressed in the stems and tillering nodes of the three materials at the four-leaf and five-leaf stages,of which the four-leaf stage had the highest expression in the stems of HX86,the five-leaf stage had the highest expression in the tillering nodes of HX91,and the three-leaf stage had the highest expression in the tillering nodes of HX79;As SPL010 was highly expressed in the tillering nodes of the three materials at the four-leaf stage,and the expression pattern was all tillering nodes The expression level of HX86 was only high in the three organs of HX86 at the three-leaf stage,and the highest expression level was only in the leaves of HX79 at the five-leaf stage.