Diversity analysis of phenotypic traits of okra young fruit

【Objective】 The diversity of phenotypic characters of young fruit of 150 okra samples was analyzed to provide reference for the breeding of okra.【Method】 The 150 okra germplasm resources from all over the world were used as test materials，12 qualitative characters， such as fruit size， fruit bending degree， fruit type， pericarp color，fruit surface， pericarp glossiness，fruit apex shape，constriction at basal part of fruit，fruit surface between ridges，pedicel surface， pedicel color，fruit posture and 9 quantitative characters， such as the number of fruit edges，number of ovaries，fruit weight，pedicle weight，fruit length，fruit width，pedicel length，pedicel width and pericarp thickness were investigated and statistically analyzed. The diversity of the phenotypic characters of the young fruit was analyzed by principal component analysis， correlation analysis and cluster analysis method.【Result】The distribution of 150 germplasm materials of okra was relatively concentrated in fruit size， fruit bending degree， fruit type， fruit surface，pericarp glossiness，constriction at basal part of fruit， fruit surface between ridges， pedicel surface and fruit posture， while the distribution of fruit color， fruit apex shape and pedicel color was relatively dispersed. 98.0% of the fruits were medium fruits，while small fruits only accounted for 2.0%；the fruit curvature was the highest in straight fruits（70.7%）；the most common fruit type was ribbed fruit （82.0%）；the surface of the fruit was mostly smooth （87.3%）；most fruit had slight gloss （91.3%）；most fruits had no constriction at basal part of fruit（66.0%）；the fruit surface between ridges was mostly flat（91.3%）；pedicel surface was mostly spiny（60.7%）；the fruit posture was mostly inclined（58.7%）and upright（36.7%）. In principal component analysis，the contribution rates of the first three principal components were 46.413%，18.050% and 13.513%，respectively，with a cumulative contribution rate of 77.976%. The coefficient of variation of 9 quantitative traits was 8.73%-25.97%，and the order of the coefficient of variation was single fruit weight>fruit ridge number>pedicel weight>pedicel length>pericarp thickness>fruit length>number of ovary chambers>fruit width>pedicel width. The test materials were divided into three major groups，with fruit types concentrated among different groups. Among them，theⅠgroup was almost ribbed fruit， the Ⅱ group was round fruit，and the Ⅲ group is ribbed round fruit.【Conclusion】 The phenotypic diversity of young fruit of the 150 okra germplasm resources have the rich genetic diversity， the traits are correlated at certain extent，which can be used as the breeding materials for new okra varieties.