Fruit trait diversity of mango(Mangiferca indica L.)germplasm resources in Lancang River basin

ObjectiveFruit traits diversity of mango(Mangifera indica L.)germplasm resources in Lancang River basin were studied to provide reference for protecting mango resources and improving the current varieties.MethodEighty-two mango germplasm resources were investigated and collected from twenty-two towns of eleven counties along Lancang River.Fruit traits of the collected germplasms were determined,and correlation and cluster analysis on fruit traits were conducted as well.ResultIn the total 82 mango resources,the resources numbers with fruit weight fell into the range of 0-50 g,50-80 g,80-120 g and 120-260 g were 6,49,19 and 8 respectively.The resources numbers of fruit shape with elliptical-shaped,oblate-shaped,ivory-shaped,oval-shaped,long oblate-shaped,peach-shaped were 66,8, 3,2,2 and 1 respectively.The resources numbers of skin color with green,yellowish green,yellowish red,greenish orange,greenish white and yellow were 48,9,12,2,2 and 9 respectively.The resources numbers of flesh color with light yellow,golden yellow,deep yellow,reddish yellow and yellowish red were 34,25,12,4 and 7 respectively.The re-sources numbers of fruit aroma with odourless,aromatic,coconut water flavor,papaya flavor,pine tar flavor and whiff flavor were 41,36,2,1,1 and 1 respectively.Variation coefficient of fruit weight(48.12%)was the highest,followed by pericarp thickness(27.27%),while fruit thickness was the lowest(13.62%).Variation coefficients of fruit length,fruit width,edible rate and soluble solid content were about 20.00%.Soluble solid content showed significant negative correla-tion(P<0.05)with fruit weight,fruit length,fruit thickness,while showed extremely significant positive correlation(P<0.01,the same below)with edible rate.There was extremely significant positive correlation between fruit width and fruit thickness,between fruit width and edible rate,and between fruit thickness and edible rate.Fruit weight presented extreme-ly significant positive correlation with fruit length,fruit width,fruit thickness and edible rate.Fruit weight,fruit length, fruit width,fruit thickness,edible rate undertook large positive load factor in the first principal component(PC1),while fruit thickness and soluble solid content undertook large positive load factor in the second principal component(PC2), which showed the seven characters were the main factors leading to biodiversity of mango resources in Lancang River. The total 82 mango resources could be divided into two groups.GroupⅠhad big fruit shape,and soluble solid content and edible rate were high in subgroupⅠ-1.GroupⅡhad small fruit shape,especially in subgroupⅡ-2,and had low edi-ble rate,which could be used as ornamental trees.ConclusionLancang River is rich in biodiversity of mango resources fruit traits. The superior genes can be reserved through domestication,hybridization,grafting and molecular breeding. The subgroupⅠ-1 has big fruit shape,high soluble solid content and edible rate,which can be used as parent materials for variety breeding and improvement.SubgroupⅡ-2 has small fruit shape and low edible percent,which can be used as orna-mental trees.