Pot experiments and field trials were conducted to investigate the changes in trichloroacetic acid (TCA) soluble silicon (Si) in the leaves of rice (Oryza sativa L.) and to examine the feasibility of using TCA-soluble...Pot experiments and field trials were conducted to investigate the changes in trichloroacetic acid (TCA) soluble silicon (Si) in the leaves of rice (Oryza sativa L.) and to examine the feasibility of using TCA-soluble Si content as an index for diagnosing Si deficiency. The TCA-soluble Si content was significantly higher in the leaves of both Si-treated and -untreated rice at the elongation stage compared with that at tillering stage. It was also higher in the Si-treated plants than in the controls throughout the whole growth period.However, whether dressed at elongation or booting stage, silicon fertilizer resulted in a significant increase in TCA-soluble Si one week to ten days after application. The same was true for the total Si accumulation in the plants. A close positive correlation was found between TCA-soluble Si and total it in plants grown on pot soils (r=0.669, P<0.01, n=26). The results obtained in the field trials revealed that the available Si extracted by sodium acetate (pH 4.0) could not predict the response of rice to added Si in the calcareous soils satisfactorily. No significant correlation was found between soil available Si content and rice yield, but TCA-soluble Si in the leaf blades of rice was significantly correlated both with rice yield (r=0.57, P<0.01,n=30) and with total plant Si (r=0.89, P<0.01, n=30). It is recommended that, with 95 per cent confidence,the critical value of TCA-soluble Si in the leaves of rice should be 52-57 mg Si kg-1, above which no positive response of rice to added Si would be expected.展开更多
Deleterious chlorine fluorescence was found to occur at the same frequency as the Raman scattering of 02 （1 A） and 02 （3 E）, seriously affecting the 02 （1 A） yield measurement in the reaction of chlorine with ba...Deleterious chlorine fluorescence was found to occur at the same frequency as the Raman scattering of 02 （1 A） and 02 （3 E）, seriously affecting the 02 （1 A） yield measurement in the reaction of chlorine with basic hydrogen peroxide by use of the Raman spectroscopy technique. To solve this problem we have taken advantage of the fact that Raman radiation is always strongly polarized while fluorescence is essentially non-polarized in a gaseous medium. When chlorine utilization of a singlet oxygen generator is 88%, 02（1A） yield reaches （42.4±7.4）% with the effect of chlorine fluorescence completely eliminated.展开更多
文摘Pot experiments and field trials were conducted to investigate the changes in trichloroacetic acid (TCA) soluble silicon (Si) in the leaves of rice (Oryza sativa L.) and to examine the feasibility of using TCA-soluble Si content as an index for diagnosing Si deficiency. The TCA-soluble Si content was significantly higher in the leaves of both Si-treated and -untreated rice at the elongation stage compared with that at tillering stage. It was also higher in the Si-treated plants than in the controls throughout the whole growth period.However, whether dressed at elongation or booting stage, silicon fertilizer resulted in a significant increase in TCA-soluble Si one week to ten days after application. The same was true for the total Si accumulation in the plants. A close positive correlation was found between TCA-soluble Si and total it in plants grown on pot soils (r=0.669, P<0.01, n=26). The results obtained in the field trials revealed that the available Si extracted by sodium acetate (pH 4.0) could not predict the response of rice to added Si in the calcareous soils satisfactorily. No significant correlation was found between soil available Si content and rice yield, but TCA-soluble Si in the leaf blades of rice was significantly correlated both with rice yield (r=0.57, P<0.01,n=30) and with total plant Si (r=0.89, P<0.01, n=30). It is recommended that, with 95 per cent confidence,the critical value of TCA-soluble Si in the leaves of rice should be 52-57 mg Si kg-1, above which no positive response of rice to added Si would be expected.
基金This work was supported by the Knowledge Innovation Program of the Chinese Academy of Sciences （No.K2009F02） and the National Natural Science Foundation of China-Youth Science Foundation （No.20603039）. The authors thank Dr. Jing Leng, Shn-yan Du, Wen-ming Tian, and Jun-hui Wang for their helpful discussions in the experiment.
文摘Deleterious chlorine fluorescence was found to occur at the same frequency as the Raman scattering of 02 （1 A） and 02 （3 E）, seriously affecting the 02 （1 A） yield measurement in the reaction of chlorine with basic hydrogen peroxide by use of the Raman spectroscopy technique. To solve this problem we have taken advantage of the fact that Raman radiation is always strongly polarized while fluorescence is essentially non-polarized in a gaseous medium. When chlorine utilization of a singlet oxygen generator is 88%, 02（1A） yield reaches （42.4±7.4）% with the effect of chlorine fluorescence completely eliminated.
