水稻配方肥添加炭酶增效剂的肥效研究

通过田间试验,比较添加不同比例炭酶量的配方肥对水稻产量和农艺性状的影响。结果表明:施用添加炭酶的配方肥能促进水稻分蘖、增加有效穗数和提高结实率,改善农业性状,从而达到增产的目的。随着炭酶添加量的增加,水稻产量也逐渐增加,以3%～4%炭酶的添加量为宜。

炭酶增效剂在早稻应用上的肥效研究

对炭酶增效剂在早稻应用上的肥效进行了试验研究,结果表明:3‰和4‰炭酶增效剂对早稻农艺性状及产量性状的影响都优于对照,而2‰炭酶增效剂对早稻没有增产效果。

早稻炭酶增效剂肥料简比试验初报

通过早稻施用添加炭酶增效剂的配方试验,结果表明:早稻在每穗实粒数、结实率和粒重等方面都有所提高,增产幅度3.2%～7.4%,且禾苗前期叶色青绿,封行快,分蘖率高,后期不早衰。

酶—炭法在高澄清度苹果汁生产上的研究与应用

本文通过单因子试验,研究了活性炭对苹果汁进行脱色处理所需的最适温度,pH,用量及作用时间。研究表明,果胶酶—活性炭为一体的综合处理可使苹果汁达到T_(625)≥99％、A_(420)≤0.06高澄度的设计标准,可明显减少活性炭用量,缩短作用时间。

The Mediation of Defense Responses of Ginseng Cells to an Elicitor from Cell Walls of Colletotrichum lagerarium by Plasma Membrane NAD(P)H Oxidases

NAD(P)H oxidases were detected in suspension cultured cells of ginseng (Panax ginseng C. A. Meyer). The activities of these enzymes were induced by an elicitor (Cle) extracted from cell walls of Col-letotrichum lagerarium. In addition, Cle induced an oxidative burst and enhanced the synthesis of saponin, activity of phenylalanine ammonialyase (PAL) , accumulation of chalcone synthase (CHS) and the transcription of a hydroxyproline-rich glycoprotein gene ( hrgp ) . Pre-treatments with DPI and quinacrine (two inhibitors of mammalian neutrophil plasma membrane NADPH oxidase) for 30 min prior to Cle addition blocked the NAD(P)H oxidase activity induced by Cle. These inhibitors also inhibited the release of H2C2, the synthesis of saponin, PAL activity and CHS accumulation. Our data revealed homology between plasma membrane NAD(P)H oxidases of mammalian neutrophil cells and ginseng suspension cells. They also indicated that deactivated NAD(P)H oxidases catalysed the release of H2O2 and that H2O2 was functioning as a second messenger stimulating PAL activity, saponin synthesis and hrgp transcription. Elevations of Ca2 + and protein phos-phorylation/dephosphorylation were required for this defense process. We propose that NAD(P)H oxidases mediate the processes of Cle-induced defense responses in ginseng suspensions, and postulate the existence of a signalling cascade including extracellular Cle stimulation, activation of plasma membrane NAD(P)H oxidases, release of H2O2, and the intracellular responses of metabolism and gene transcription in ginseng suspension cells.

Effects of Biochar on Soil Enzyme Activity and Mechanism of Action

[Objective] The aim was to detect effects of biochar on soil enzyme activity and mechanism. [Method] Soils were sampled from experimental fields of Shanxi Academy of Agricultural Sciences and added with charcoals in different types in order to analyze dynamic changes of alkaline phosphatase and cellulase activities and effects of charcoals on soil enzyme activities. [Result] By applying charcoal, enzyme activity of soil samples all improved and the increase degree was higher of alkaline phosphatase than cellulase activity. Mid-temperature charcoal at 8% is the best. [Conclusion] The research provides references for effects of biochar on physi- cal and chemical properties.

Interactions of Marsh Orchid(Dactylorhiza spp.)and Soil Microorganisms in Relation to Extracellular Enzyme Activities in a Peat Soil

The nature of the interactions between microbes and roots of plants in a peaty soil were studied in a laboratory- based experiment by measuring activities ofβ-glucosidase,phosphatase,N-acetylglucosaminidase,and arylsulphatase.The experiment was based on control(autoclaved),bacteria-inoculated,and plant(transplanted with Dactylorhiza)treatments, and samples were collected over 4 sampling intervals.Higher enzyme activities were associated with the bacteria-inoculated treatment,suggesting that soil enzyme activities are mainly of microbial origin.For example,β-glucosidase activity varied between 25-30μmol g^(-1)min^(-1)in the bacteria-inoculated samples whilst the activity of the control ranged between 4-12μmol g^(-1)min^(-1)A similar pattern was found for all other enzymes. At the end of the incubation,the microcosms were destructively sampled and the enzyme activities determined in bulk soil,rhizospheric soil,and on the root surface.Detailed measurement in different fractions of the peat indicated that higher activities were found in rhizosphere.However,the higher activities ofβ-glucosidase,N-acetylglucosaminidase,and arylsulphatase appeared to be associated with bacterial proliferation on the root surface,whilst a larger proportion of phosphatase appeared to be released from root surface.

Enzymatic Method for Rapid Determination of Oxalic Acid in Bleaching Filtrates from the Pulp and Paper Industry

Bleaching with oxygen-containing agents and recirculation of process streams in the pulp and paper industry has increased the accumulation of oxalic acid and danger for precipitation of calcium oxalate encrusts, scaling. Analysis and control of oxalic acid in bleaching filtrates is therefore becoming increasingly important in the pulp and paper industry. Chromatographic methods, such as IC and HPLC, are generally more time-consuming but are valuable as standard methods for determination of oxalic acid. However, the instrumentation needed is expensive and stationary. In this study, an enzymatic method based on oxalate oxidase and peroxidase was developed to determine oxalic acid in authentic bleaching filtrates using a spectrophotometer. The results showed that bleaching filtrates contain some compounds interfering with the enzymatic method. Pretreatment of the samples with activated charcoal was a successful approach for decreasing problems with interference. By using dilution followed by charcoal treatment, the results obtained from five bleaching filtrates with the colorimetric method correlated very well with those obtained using IC. This study offers a selective, fast and mobile analysis method to determine oxalic acid in bleaching fiRrates from the pulp and paper industry, The convenient enzyme-based method improves the possibilities for control of critical oxalic acid concentrations in closed-loop bleaching streams.

Study of the Action Mode of Wickerhamomyces anomalus against Colletotrichum gloeosporioides

Colletotrichum gloeosporioides is the causal agent of anthracnose disease in fruits and vegetables, representing a global problem. The use of biocontrol agents has proved effective against fungal diseases in a wide variety of products. In this work, the antifungal activity of Wickerhamomyces anomalus against C. gloeosporioides isolated from contaminated avocados was evaluated. The antagonism and volatile compound inhibition were measured on Petri dishes. In the mixed cultures, the mycelia damage was observed by scanning electron microscope （SEM）. Chitinase and glucanase production by the antagonism was quantified by the reducing sugars method, and biofilm formation was evaluated with 1% crystal violet. The yeast W. anomalus could reduce the growth of C. gloeosporioides up to 65% by direct antagonism and 10% by volatile compounds. The antagonist did not allow the conidia germination and mycelia growth in any of the tested formulations. SEM showed mycelial damage caused by W. anomalus. The antagonist showed adhesion to the mycelium by a polysaccharide biofilm. The presence of mycelium stimulated the hydrolytic enzyme production with the maximal activity of 21.4 U/mg for chitinases at 24 h and 10 U/mg for glucanases at 60 h. These results showed that W. anomalus used together different mechanisms to express its antifungal activity against C. gloeosporioides. This study might be the first report for this phytopathogen isolated from avocado fruits, which could represent an opportunity to establish biocontrol of diseases for this agricultural product.