基于形态特征的越南北部地区柑橘种质资源遗传多样性评价OA

[Objective]This study aimed to systematically assess the genetic diversity of local mandarin(Citrus reticu-lata Blanco)accessions in northern Vietnam based on morphological characteristics,which could provide reference for mandarin accessions conservation and new variety breeding in Vietnam.[Method]A total of 32 local mandarin accessions were collected from major cultivation areas across northern Vietnam.For each accession,samples of leaves,flowers,and fruits were collected from mature and healthy trees.Morphological characteristics including leaf,flower,and fruit traits were detected.Cluster analysis,correlation analysis,and principal component analysis were conducted to reveal the genetic characteristics among the citrus accessions in northern Vietnam.[Result]There was a high degree of uniformity in leaf qualitative traits,rich morphological and reproductive diversity in flower traits and fruit traits,particularly in traits related to flower size,pollen viability,fruit set rate,fruit size,weight,seed number,flavor,and edible portion.50%of the accessions exhibited traits typical of unselected or wild mandarins:small,seedy,and sour fruits,while accessions C14 and C29 showed large,low seed number,and sweet to slightly sour fruits.Cluster analysis grouped the 32 citrus accessions into two major clusters and several sub-clusters,suggesting close genetic relationship within the accessions.There was positive correlation between fruit weight and edible portion weight,while there was negative correlation between seed number and total soluble solid content.The cumulative contribution rate of principal component 1 and princi-pal component 2 was 37.5%.[Conclusion]The study confirms that mandarin accessions in northern Vietnam possess rich morphological diversity,which is crucial for breeding improved mandarin accessions with desirable traits such as enhanced fruit quality and consumer preference.