[Comparison on submergence tolerance of different type rice at tillering stage in lower reaches of Yangtze River].

The agronomic traits, physiological characteristics and yield traits of 9 rice varieties popularized in lower reaches of Yangtze River were investigated under submergence stress at the tillering stage. The differences of environmental adaptability to submergence stress for conventional japonica rice, indica hybrid rice and hybrid japonica rice, were also analyzed and compared. The results showed that the stem and the upper three leaves under submergence stress were elongated compared with the control. And the elongation of the different varieties was shown as, hybrid japonica rice > indica hybrid rice > conventional japonica rice. As to the numbers of tillers and green leaves, and the aboveground dry mass, the reduction of indica hybrid rice was all between hybrid japonica rice and conventional japonica rice. The damage of hybrid japonica was the lightest. The content of MDA in the leaves of conventional japonica rice increased, while the activities of SOD and CAT decreased. However, the performances of hybrid japonica rice and indica hybrid rice were opposite with conventional japonica rice. The yield loss of conventional japonica rice was significantly higher than those of the other types of rice. These results suggested that the submergence tolerance ability of hybrid japonica rice is superior to indica hybrid rice, and the submergence tolerance ability of conventional japonica rice is the weakest.

Determination of loganin and paeonol in Liuwei Dihuang pills by HPLC amalgamated of double UV waves / 中国中药杂志

<p><b>OBJECTIVE</b>To establish a high performance liquid chromatographic (HPLC) amalgamated to double UV waves method for simultaneous determination of loganin and paeonol in Liuwei Dihuang pills.</p><p><b>METHOD</b>A HPLC method was developed. The separation was carried out on a Agilent Zorbax SB C18 column (5 microm, 4.6 mm x 250 mm). The mobile phase consisted of water (A) and acetonitrile (B) with linear linear gradient elution [0-8 min, (B) from 1% to 12%; 8-21 min, B keep 12%; 21-40 min, (B) from 12% to 90%; 40-50 min, B keep 90% for 10 min]. The detection was Photodiode Array with the detection wavelengths were at 236 nm and 274 nm. The column temperature being 30 degrees C and the flow rate was 1.0 mL min(-1). Extracting the chromatergraph from 274 nm and 236 nm, we amalgamated the two chromatographs by matlab programmed.</p><p><b>RESULT</b>The calibration curves of loganin and paeonol were linear in the ranges of 0.0362-1.09 microg (r =0. 9998) and 0.0450-1.35 microg (r =0.9998), respectively. The average recoveries of loganin and paeonol were 97.3% (RSD 1.4 %) and 103.0% (RSD 1.9%), respectively. Three different batches of Liuwei Dihuang pills were determined with this method.</p><p><b>CONCLUSION</b>This is a more convenient, reasonable and credible quality control method for the traditional Chinese medicine.</p>