Creation Of Peanut Mutants And Expression Analysis Of Lipid Phosphate Phosphatase Gene

Arachis hypogaea L.,also known as"longevity pod"and"paraffin",originated from South America.In China,it is not only an important cash crop but also a major oil crop in the north.For a long time,the production of peanuts in China has ranked first in the world.However,the economic benefits are relatively low without the high-quality specialty varieties.Therefore,we should achieve breakthroughs in germplasm,and breed new peanut varieties with high yield and high quality.The use of mutagenesis to create mutant materials is an important way to improve crop germplasm and lay a foundation for theoretical research.In this study,we created peanut mutants by peanut varieties?germplasms?which are widely used in peanut production,and opens up a new way for cultivating peanut varieties with good comprehensive characters in the future.The research contents are as follows:Firstly,eight cultivated peanut varieties?germplasms?,Luhua 6,Huayu19,Huayu20,Huayu 23,Huayu 32,Huayu 33,Silihong and Dragon peanut,were induced by ethymethane sulfonate?EMS?,⁶⁰Co-?or fast neutron radiation,containing a population of 1623 mutant plants.Secondly,some important agronomic traits and main quality traits were observed and measured,and statistical analysis was performed.It was found that the total pod weitht was extremely significantly positively correlated with shelling percentage,and extremely significantly negatively correlated with the leaf length.The oleic acid content showed a very significant negative correlation with the palmitic acid content,and a very significant positive correlation with the oleic/inoleic ratio?O/L?.Path analysis indicates that the order in which the agronomic traits affect yield is:pod length?1.202?>leaf width?0.936?>main stem height?0.240?>number of pods per plant?0.167?>half catty pod number?-0.624?>100-pod weight?-0.641?>main stem width?-1.355?.The order of the influence of quality traits on O/L value is:oleic acid content?1.522?>palmitic acid content?0.387?>oil content?-0.271?>protein content?-0.273?>sucrose content?-0.698?.Thirdly,detection of AhFAD genes of 154 peanut high oleic mutants using KASP method found that an insertion of A at the 442bp site of AhFAD2B appeared in these materials,which may increase the oleic acid in peanuts.For these mutants,the oleic acid content is between 66.46-80.30%.The linoleic acid acid content is between1.29-13.34%.The O/L value is between 4.98-62.31.Lastly,eight lipid phosphate phosphatase?LPP?genes were cloned from peanut variety Huayu 33,and named as AhLPP1,AhLPP2,AhLPP4,AhLPP?1,AhLPP?2,AhLPP?,AhLPP?,AhLPP?respectively.They encodes 335,322,284,228,198,227,403,293 amino acids,respectively.All of them belong to the LPPs protein family.Subsequently,the cloned genes were used to perform sequence similarity comparison and phylogenetic analysis by related tools.At the same time,the expression of AhLPP genes were detected by quantitative real-time PCR in different tissues,different developmental stages of seeds and 5 hormones and 4 abiotic stresses.The results showed that the AhLPP genes were highly similar to other plants'LPPs and may participate in the synthesis of seed oils.AhLPP2,AhLPP?,AhLPP?genes were differentially expressed under the treatment of five hormones and four abiotic stresses,while other LPP genes were differentially expressed following exposure to part treatments.This study provides a theoretical basis for clarifying the function of LPP genes in the synthesis of peanut oil and improving abiotic stress resistance,and enriches new gene resources for seed improvement of peanut.These studies provide a wealth of germplasm materials and theoretical basis for peanut genetic improvement and functional gene identification.