It is important to determine the isoflavone components by high-performance liquid chromatography (HPLC) for the molecular assistant selection of isoflavone in soybean. Based on the standard samples of 12 isoflavone components, the isoflavone components were analyzed using the determination of absorbance peaks method by HPLC. The results showed that there were different maximum ultraviolet (UV) absorbance for the aglycones of daidzein, glycitein, and genistein, which were at 250, 257, and 260 nm, respectively. A linear gradient elution of acetonitrile (13-30%) containing 0.1% acetic acid as a mobile phase was applied on a YMC-C18 column at 35℃. The 12 isoflavone components were determined using the UV detector by HPLC. We concluded that this is a rapid and precise method which adapted to determine the large numbers of samples with microanalysis.
SUN Jun-mingSUN Bao-liHAN Fen-xiaYAN Shu-rongYANG HuaAkio Kikuchi
Sclerotinia sclerotiorum (Lib.) de Bary, as an ubiquitous phytopathogenic Ascomycete fungus capable of infecting a wide range of plants, has increased in importance for oilseed rape production worldwide in recent years. The objective of this research was to determine the effectiveness of two measurements of disease rating in predicting the field reaction of cultivars to sclerotinia stem rot. One hundred and ten cultivars or lines of oilseed rape were repeatedly evaluated the disease severity index (DSI) and lesion length for their resistance to nine isolates of S. sclerotiorum in two field stations. There were greatly significant differences between two stations, among isolates, among population of cultivars for the disease severity index and lesion length, and also significant station×isolate interaction for lesion length and population×isolate interactions for DSI and lesion length, but interactions of station×isolate for DSI were not significant. Cultivars such as Pomorzanin and Lisek consistently had the lowest disease severity ratings in the field tests. However, most of cultivars were susceptible to sclerotinia stem rot in the field test. A positive correlation between the mean DSI and lesion length was found for both isolates (Sc23 and B1). The correlations ranged from 0.23 to 0.83 at various plots, with nine of the twelve correlations significant. The correlations for disease caused by different fungal isolates were statistically significant difference. These correlations ranged from -0.44 to 0.90, with nine of the thirty-two correlations significant. It indicated that resistance to some isolates was significantly correlated and selection of some varieties for resistance to one isolate appeared to improve resistance to other isolates.
