薄皮甜瓜糖酸含量及其与果实性状的灰色关联度分析

Sugar and Acid Contents of Thin-Skinned Melons and Their Grey Relational Analysis to Fruit Characters

为了探明与薄皮甜瓜糖酸含量相关的性状指标,对不同来源的18份薄皮甜瓜种质的糖酸含量进行测定,采用灰色关联度法分析糖酸含量与果实性状的相关性。结果表明,不同甜瓜种质间糖酸组分含量差异显著,总体上梨瓜和香瓜变种的果糖、葡萄糖、蔗糖含量较高,总糖含量一般在40.00 g/kg以上,柠檬酸和苹果酸含量较低,总酸含量低于1.30 g/kg;泡瓜和酸瓜变种糖组分含量低而酸组分含量高,其总糖含量低于20.00 g/kg,总酸含量高于1.70 g/kg。不同甜瓜种质的果糖、葡萄糖和苹果酸含量的变异系数均高于50.00%、香农多样性指数均大于1.60,种质间差异明显,显示出丰富的多样性。灰色关联度分析结果表明,总酸含量与单果鲜质量、果纵径的关联度较大,总糖含量、糖酸比均与可溶性固形物含量、果肉厚度关联度较大。

To identify the morphological indices related to the sugar and acid contents of thin-skinned melons, the sugar and acid contents of 18 thin-skinned melon accessions were determined, and grey relational analysis was used to seek the correlation between sugar, acid contents and fruit characters. The results showed a distinct significant difference of sugar and acid contents among germplasms. Overall, var. chiueusis and vat. makuwa had high levels of fructose, glucose and sucrose but low levels of citric and malic acid, with total sugar content of over 40.00 g/kg and total acid content of below 1.30 g/kg. However, var. ruomordica and var. acidulus had a low level of sugar but a high level of acid, with total sugar content of below 20. 00 g/kg and total acid content of over 1. 70 g/kg. The three variation coefficients of fructose, glucose and malic acid contents were more than 50.00% with Shannon＇ s diversity index exceeding 1.60,which indicated a significant difference between the accessions and a high level of genetic diversity. Grey relational analysis showed that total acid content was mainly related to single fresh fruit weight and fruit length, and total sugar content and sugar-acid ratio were mainly related to soluble solid content and flesh thickness.