16份桄榔种质主要农艺性状的遗传多样性分析

Genetic diversity analysis of main agronomic characters of 16 Arenga pinnata germplasm resources

【目的】分析桄榔种质资源农艺性状的遗传多样性,为桄榔种质资源的开发利用和优异种质选育提供理论依据。【方法】以采集自不同地区的16份桄榔种质为试验材料,调查和测定其15个表型性状(农艺性状),采用遗传变异、相关分析、主成分分析和聚类分析法进行遗传多样性分析和综合评价。【结果】16份桄榔种质的表型性状均具有丰富的遗传多样性,其Shannon wiener指数(H′)变化范围为0.832~2.100,平均为1.671,其中株高的H′最高(2.100)。不同地区桄榔种质农艺性状间的差异均达显著(P<0.05)或极显著(P<0.01)水平,变异系数范围为5.14%~102.19%,其中,除叶厚的变异系数为5.14%外,其他农艺性状的变异系数均大于10.00%,尤其果重的变异系数最大(102.19%)。从15个农艺性状中共提取5个特征值大于1.00的主成分,其累积贡献率达88.07%,能综合反映桄榔种质农艺性状的大部分信息。综合评价结果表明,V6、V5、V11、V1、V4和V12种质的综合得分分别为151.59、140.12、134.12、132.54、130.78和126.70,综合表现较好。聚类分析结果表明,16份桄榔种质可分为三大类群,其中,第一类群种质(V2、V7、V8、V9、V10、V13、V14、V15和V16)表现为种子粒重和果重较重,种子纵径和横径较长,叶厚、叶长及植株的胸径、株高和冠幅较小,果形为圆凹、圆凸或长凹,果色为绿色和黑色;第二类群种质(V1、V11和V12)表现为种子厚度较小,叶长、叶宽及植株的胸径较大,果形为圆凸、长凹或长凸,果色为黄色和绿色;第三类群种质(V3、V4、V5和V6)表现为种子体积和纵径较小,叶厚较厚,叶宽和植株的胸径较小,株高和冠幅较大,果形为圆凹和长凹,果色为黄色和绿色。【结论】16份桄榔种质的遗传多样性较丰富,不同地区的桄榔种质资源存在较大变异性,其中种质V6、V5和V11综合表现较好,是较优异种质,适合用于亲本选配;基于农艺性状进行桄榔种质资源遗传多样性评价方法简单可行,结合主成分和聚类分析有助于更快选育出符合育种目标的优异桄榔种质。

【Objective】Comprehensive evaluation of the genetic diversity of agronomic traits of Arenga pinnata germplasm resources provided a theoretical basis for the development and utilization of A.pinnata germplasm resources and the breeding of excellent germplasm.【Method】In this study,15 phenotypic traits(agronomic traits)were investigated and determined in 16 A.pinnata germplasms collected from different areas.Genetic variation,correlation,principal component and cluster analysis were used to analyze and comprehensively evaluate the genetic diversity of germplasm.【Result】The phenotypic traits of 16 A.pinnata germplasm resources all have rich genetic diversity.Its Shannon wiener index(H′)ranged from 0.832 to 2.068,with an average of 1.671,and the H′of plant height was the highest at 2.100.The differences in agronomic traits of sugar palm germplasm resources in different regions all reached significant(P<0.05)or extremely significant(P<0.01)levels,with the coefficient of variation ranging from 5.14%to 102.19%.Among them,except the coefficient of variation of leaf thickness,which was 5.14%,the coefficients of variation of other agronomic traits were all greater than 10.00%,especially the coefficient of variation of fruit weight was the largest(102.19%).Five principal components with characteristic values greater than 1.00 were extracted from 15 agronomic traits,and their cumulative contribution rate reached 88.06%,which can comprehensively reflect most of the information of the agronomic traits of A.pinnata.The comprehensive evaluation results showed that the comprehensive scores of V6,V5,V11,V1,V4 and V12 germplasms were 151.59,140.12,134.12,132.54,130.78 and 126.70,respectively,showing good comprehensive performance.The cluster analysis results showed that the 16 sugar palm germplasm resources can be divided into three categories.Among them,the first group A.pinnata germplasm(V2,V7,V8,V9,V10,V13,V14,V15 and V16)exhibited the showed heavier grain weight and fruit weight,longer seed longitudinal and transverse diameter.The leaf thickness,leaf length,diameter at breast height,plant height and crown width were smaller,the fruit shape was round concave,round convex or long concave,and the fruit color was green and black.The second group A.pinnata germplasm(V1,V11 and V12)showed that smaller seed thickness,larger leaf length,leaf width and diameter at breast height,fruit shape was round-convex,long-concave or long-convex,and fruit color was yellow and green;The third group A.pinnata germplasm(V3,V4,V5 and V6)showed smaller seed volume and longitudinal diameter,thicker leaf thickness,smaller leaf width and diameter at breast height,and the larger plant height and crown width.The fruit shape was round concave and long concave,and the fruit color was yellow and green.【Conclusion】The genetic diversity of 16 A.pinnata germplasm resources is relatively rich,and the A.pinnata germplasm in different regionshave great variability.The comprehensive performance of germplasm V6,V5 and V11 is relatively good,which is more excellent germplasm,suitable for parent selection match.The method of evaluating the genetic diversity of A.pinnata based on agronomic traits is simple and feasible.Combining principal component and cluster analysis is helpful for faster selection of excellent A.pinnata germplasm that meets the breeding goals.