利用傅里叶变换红外光谱法(FTIR)测定了不同倍性(二倍体、 三倍体、 四倍体)罗汉果叶片的红外光谱, 以不同波数段上的吸光度为指标, 通过主成分分析和聚类分析研究了罗汉果的倍性差别及遗传关系。 结果表明, 罗汉果在倍性与亲缘遗传上表现出: 倍性差别越大, 在主成分三维排序图中的相对位置和聚类图中的遗传距离均越远, 呈现出2×<3×<4×的规律; 亲缘关系越远, 遗传距离也越远; 三倍体子代在母本相同时, 不同的父本对其亲缘与遗传关系有一定的影响。 由此可知, 基于主成分分析和聚类分析的FTIR研究能在一定程度上揭示出罗汉果不同倍性的差别及其相互间的遗传关系。

Siraitia grosvenorii was an important Chinese traditional medicine. The spectra of leaf of diploid, triploid and tetraploid Siraitia grosvenorii were determined by Fourier transform infrared spectroscopy (FTIR) with OMNI sampler directly, fast and accurately. And based on the indices of wave number-absorbance from different bands and through comparison of differences of these infrared spectra the ploidy difference and genetic relationship of Siraitia grosvenorii were studied by the methods of principal component analysis (PCA) and cluster analysis. The results showed that for the ploidy, the position relationship of PCA three-dimensional-plot and the distance coefficient of clustering analysis plot between diploid and tetraploid were most remarkbly different, and the triploid was basically between diploid and tetraploid, so the ploidy was more different, the position relationship of PCA and the distance coefficient of clustering analysis were further, and the law was: 2×<3×<4×. At the same time, the genetic relationship was further with each other while the position relationship of PCA and distance coefficient of clustering analysis was further too. And the genetic relationship of triploid was affected by the different male parent while their female parent was the same one. Therefore, using FTIR based on PCA and cluster analysis we could reveal the difference of ploidy and the genetic relationship between Siraitia grosvenorii to a certain extent. FTIR could be used for excellently polyploidy species breeding of Siraitia grosvenorii.