Rice plant growth and yield: foliar application of plasma activated water

Plasma activated water(PAW)was prepared for 10 min to be applied one tofive times as a foliar spray to rice plants,to investigate plant growth,yield and the concentrations of total soluble protein and sugar in the rice grains produced.The results reveal that(1)the plant height,stem diameter,dry weight,chlorophyll and total carotene concentrations were improved by∼15%,∼25%,∼24%,∼47%and∼45%,respectively,with respect to control,(2)defense mechanisms of the plants treated with PAW were improved,(3)concentrations of total soluble protein and sugar were enhanced in the rice grains of PAW treated plants and(4)yield was increased by∼14%.

Studies on Some Plant Extracts for Their Antimicrobial Potential against Certain Pathogenic Microorganisms

The aim of the present study was to check the antimicrobial potential of eleven different aqueous leaf extracts on Xanthomonas campestris, Agrobacterium rhizogenes and Aspergillus fumigatus based on formation of the zone of inhibition (ZOI). Prosopis juliflora showed maximum and significant inhibitory effect on the growth of all the three pathogens. In case of Xanthomonas campestris the effect of this plant extract was almost equal to the strength of Streptomycin 10 mcg, (the metric system uses the term mcg to represent micrograms). Aqueous extracts of some plants formed low zone of inhibition. While some plant extracts were comparatively more effective against all the three pathogens (Xanthomonas campestris, Agrobacterium rhizogenes and Aspergillus fumigatus).

In-Vitro Efficacy of Certain Essential Oils and Plant Extracts against Three Major Pathogens of Jatropha curcas L.

Antifungal activity of plant extracts and essential oils of six different plant species was tested against three pathogenic fungi, viz., Alternaria alternata, Colletotrichum gloeosporioides and Fusarium moniliforme isolated from Jatropha curcas L. using Poison Food Technique. All the samples tested were found effective in-vitro. More than 60% inhibition of growth of individual fungal species was observed at 100 ppm. Maximum inhibition was observed at concentration of 1000 ppm. However, among the essential oils tested Cinnamomum impressinervium exhibited the strongest activity (80%) in the case of Colletotrichum gloeosporioides and Alternaria alternate and 78.6% in the case of Fusarium oxysporum at concentration of 1000 ppm followed by Cinnamomum tamala, Cymbopogon jwarancusa and Cymbopogon citratus respectively. Among the plant extracts tested, Catharanthus roseus exhibited stronger activity in comparison to Tithonia diversifolia. Inhibition percentage of all the essential oils and plant extracts increased with the increase in concentration.

Isolation and Structural Speculation of Herbicide-Active Compounds from the Metabolites of Pythium aphanidermatum

Natural herbicides, or environment-friendly bioherbicides have been attracted more and more attentions. Isolation and structural identification of natural herbicide-active compounds from plant pathogens has been proved to be an effective approach for novel lead discovery of the pesticide development. In this study, the metabolites of the mutant strain PAM1, which obtained from PA1 of Pythium aphanidermatum （Eds.） Fitzp by ultraviolet radiation were separated and identified by HPLC, NMR, and IR. The results revealed that three active compounds including 4-hydroxy-3-methoxycinnamic acid and two indole derivatives, exhibited inhibition activity on the elongation of radical and coleoptile of Digtaria sanguinalis （L.） Scop.

Ligninolytic enzymes production by endophytic fungus Diaporthe phaseolorum(Desm.)Sacc.under the influence of different carbon and nitrogen sources

Endophytic fungi are being investigated for their ability to create industrially relevant secondary metabolites.In recent years,there has been a surge in interest in these fungi as a source of novel enzymes,particularly hydrolytic enzymes.The present study investigated the effect of different carbon,organic and inorganic nitrogens on the growth and ligninolytic enzyme production by the endophytic fungus Diaporthe phaeolorum.The fungus was isolated from the leaves of Dillenia indica and analyzed by morpho-molecular basis.The fungus showed promising results for in vitro production of ligninolytic enzymes.Sucrose was the most favorable carbon compound for growth among all the carbon compounds tested.It displayed maximum lignin peroxidase(Lip)activity in fructose(3.5 U/ml),followed by pectin(2.60 U/ml)and glucose(2.53 U/ml).Glucose gave the highest manganese peroxidase(MnP)activity i.e.,6.88 U/ml followed by starch,sucrose and raffinose.Similarly,the maximum laccase activity was 44.5 U/ml in pectin.Potassium nitrate and L-asparagine were the best inorganic and organic nitrogen for growth.In the case of ligninolytic enzyme production,ammonium acetate and ammonium phosphate were the best media for LiP and MnP,whereas laccase production was highest in ammonium nitrate supplemented medium.In organic nitrogen sources,medium supplemented with DL-tryptophan gave the highest Lip production,whereas MnP and laccase production was observed in the medium containing L-tyrosine and L-asparagine.To the best of our knowledge,this is the first report related to the growth and ligninolytic enzyme production by Diaporthe phaseolorum.The findings from the study will assist researchers in improving the production of ligninolytic enzymes by this fungus under in vitro conditions on an industrial scale.