Individual Selection Of The Oil Use Tree Peony Based On Comprehensive Traits Analysis

Paeonia,which belongs to Moutan section of Paeonia,has been cultivated for a long history,and distributed widely.It has been researched that Paeonia has high seed yield and unsaturated fatty acids content especially high a-linolenic acid content in its seed oil.Hence,oil tree peony shows huge potential to be a new woody oil crop in the future.Due to tree peony’s ornamental and medicinal cultivation in the long term of history,the researches of seed yield,oil content,fatty acids content,and oil use germplasm selection were rarely reported Therefore,this literature chose different germplasms as experimental materials to analysis the seed yield,oil content and fatty acids contents and these interrelation;extensively collected tree peony seed samples to construct rapid determination model for seed oil and fatty acids content based on near infrared spectroscopy technology(NIRS);and selected 205 genotypes of P.rockii as materials to carry out association analysis by TASSEL,using SSR markers on the basis of investigation of 3 consecutive years,in order to explore allele variation of oil and other important traits;at last,this literature selected several superior individual plants via grey relational grade analysis,supporting for the innovation and efficient breeding of oil tree peony germplasm.The main results were as follows:(1)The 30 different cultivars were used as materials to analysis 38 characters such as yield,leaves,flowers,fruit and oil performed on R language.As a result,the CV of all the traits were 3.48%～111.00%.And the seed yields of P.rockii and P.ostii were significantly higher than other varieties,and the seed yields of cultivars belong to northwest group were generally higher than other cultivar groups.The Zhongyuan and Japan cultivar groups had similar performance in aspect of seed yield.However,Europe and America cultivars had no seed production,which showed the same phenomenon at P.delavayi.The multiple analysis of the related traits showed that the main factors affecting the yield per plant were the fruit weight per plant,the number of valid fruits per plant and the seed rate(2)Based on NIRS to establish a rapid detection model for different fatty acids contents of tree peony seeds,a small amount seed(～20g)of 115 samples and 447 single seeds were collected,respectively.Generally,the small amount seed models were more effective than the single particle models.What’ more,Linolenic acid(C18:3)model of small amount showed the highest accuracy,the ratio of performance to deviation(RPD)>3.And the best pretreatment method of husked seed samples was multiple scattering correction(MSC),the intact seed samples of the best pretreatment method was MSC+the first derivative.However,the single seed models could only be used for preliminary screening the linolenic acid(C18:3)and linoleic acid(C18:2)inner single seed(3)The genetic diversity of P.rockii breeding population was analyzed based on 102 polymorphic SSR markers.The group structure was analyzed on the STRUCTUR software,which determined the group K=2.Then,the value of kinship between individuals within the population were analyzed by the SPAGeDil.5 software,which showed that individuals with kinship=0 accounted for 51.65%,individuals with kinship>0.3 accounted for 1.44%only.The association analysis was operated under GLM and MLM models on TASSEL software based on the phenotypic traits of 3 consecutive years.There were 232 interconnects between 32 characters and 70 SSR markers repeatedly detected in different years under the GLM model,with the average of phenotypic explained variation in the scope of 0.0381～0.2804;However,under the MLM model,only 21 interconnects between 7 characters and 19 SSR markers repeatedly detected in different years,the average phenotypic explained variation ranged from 0.0030 to 0.1295.At last,it can repeatedly detected 6 characters associated with 17 markers of the 83 alleles in different models and different years.And then allelic variation in phenotypic effects had been analyzed,the consistent effects associated alleles was 72,including 38 increasing effects and 34 reducing effects.The markers ps207,ps328 and ps356 were associated with yield,the explained variation of which were ranged from 0.0065 to 0.0216;meanwhile ps345 associated with linolenic acid,the explained variation of which was 0.0928(4)From the P.rockii population we selected seven economic index,such as seed yield unit crown(Kl),fruit weight unit crown(K2),the number of effect fruit unit crown(K3),hundred seed weight(K4).seed rate(K5),oil content(K6)and linolenic acid(K7),and then screened superior individuals by grey relational grade analysis.It indicated that a total of 4 individuals could be screened out when correlation degree>0.65,which named as ZB025,ZB016,ZB002,ZB050 with better comprehensive performance and the seed yield 329.07 g/m2,338.79g/m2,346.40 g/m2 and 356.50 g/m2 respectively.