Introduction evaluation and genetic diversity analysis of 56 lotus varieties

【Objective】Introduction evaluation and genetic diversity analysis of 56 introduced lotus varieties were conducted，to screen lotus varieties with high introduction value and good genetic diversity，and to provide reference for the introduction，development and utilization of lotus.【Method】The ornamental value and adaptability of 56 lotus varieties were evaluated by analytic hierarchy process（AHP）to construct a comprehensive evaluation model of introduction value. Besides，the genetic diversities of introduced lotus varieties were studied using SSR fluorescent markers combined with capillary electrophoresis.【Result】The comprehensive evaluation model of lotus introduction value had 2 first-level indicators and 9 second-level indicators. In the weight ranking of constraint layer（C）to target layer（A），C₂（adaptability）had a greater weight than C₁（ornamental traits），indicating that the adaptability of introduced varieties was the most important. Among C₁（ornamental traits），P₆（flowering density）had the highest weight value（0.4707），followed by P₅（florescence of single flower）（0.2043）and P₇（population florescence）（0.1318）. In C₂（adaptability），the weight value of P₈（growth situation）（0.7501）was greater than the weight value of P₉（reproductive ability）（0.2499）. The top 3 indicators affecting the evaluation of ornamental lotus introduction value were P₈（growth situation），P₉（reproductive ability） and P₆（flower density）. Through comprehensive evaluation，4 excellent varieties with a composite score of 9 or above were selected，including Monaihuadie，Xiangxuehai，Hongfugui and Caiyunzhuiyue，along with 15 better varieties，31 good varieties，and 6 varieties with low introduction value；8 pairs of SSR fluorescent primers in 56 lotus varieties were used to detect 70 alleles，the effective allele number（Ne）ranged from 3.0742 to 6.2408，the Shannon diversity index（I） ranged from 1.2765 to 1.9657，and the polymorphic information content（PIC）ranged from 0.6392 to 0.8202. The expected heterozygosity（He）of all SSR molecular markers was higher than the observed heterozygosity（Ho）；the genetic similarity coefficient（GS）of 56 lotus varieties was 0.5862-0.9857，with an average value of 0.7617. Cluster analysis showed that the tested lotus varieties could be divided into 3 major groups at the GS of 0.7200，and group II could be divided into three subgroups at GS of 0.7800.【Conclusion】The growth situation，reproductive ability and flowering density exert the most significant influence on the comprehensive evaluation results. The 4 excellent varieties can be used as the key development and utilization objects，while better and good varieties can be moderately developed，and 6 varieties with low introduction value are not suitable for promotion. The tested 8 pairs of SSR primers show good polymorphism among 56 tested lotus varieties，but the genetic basis of the tested lotus is relatively narrow.