Abstract:

In order to explore the variation and genetic tendency of multiple traits of loquat fruit in the hybrid offspring，the F₁ loquat lines of‘Ninghaibai’（white pulp，female parent）and‘Oobusa’（yellow pulp，male parent）were used as materials，a total of 14 traits，including quality，color，secondary metabolic functional components，and cell wall components were studied in the mature fruits of 100 lines and their parents. The comprehensive quality of hybrid offspring fruit was evaluated by principal component analysis. The results showed that the 10 traits，including fruit weight，total soluble solids（TSS），gloss brightness（L^*）and color saturation（C^*），total phenolic，flavonoids，pectin，cellulose，total hemicellulose and total lignin were widely separated in the F₁ generation with a normal distribution. Four traits，including titrable acid（TA），ratio of TSS to TA，hue angle（H^*），and carotenoid content showed a skewed distribution in F₁ generation. TSS and TA showed a tendency of higher genetic variation，L^*，C^*，H^*，carotenoid content，pectin content and cell wall cellulose content showed a tendency of intermediate genetic variation，while fruit quality，solid acid ratio，total phenol content，flavonoids content，total hemicellulose content and total lignin content showed a trend of small genetic variation. Correlation analysis showed that fruit quality was positively correlated with L^*，C^*，carotenoid content，total phenol content and total hemicellulose content，and negatively correlated with TSS，H^*，flavonoids content and pectin content. According to the principal component analysis，five principal components with eigenvalues greater than 1 were obtained，and the cumulative contribution rate was 70.424%，which were mainly summarized into three aspects：fruit color，fruit flavor and fruit texture，and 26 excellent quality lines were successfully screened out according to the comprehensive quality score.

Key words: loquat, fruit trait, genetic tendency, principal component analysis, comprehensive quality evaluation