Glucose Nitrate Research Articles

Potential Secondary Metabolites of Streptomyces sp. and Trichoderma sp. in Suppressing the Percentage of Spodoptera litura Attacks on Corn Plants

Spodoptera litura F. (Lepidoptera:Noctuidae) is one of the main pests on corn which is polyphagous and can cause crop failure due to damage to the leaves of the plant. Secondary metabolite compounds produced by microorganisms have many roles and functions, namely as compounds to protect plants from pest attacks. Streptomyces sp. and Trichoderma sp. are biological control agent which have the potential to produce chitinase enzymes capable of degrading the cell walls of larval and pupal stages. This study aims to determine the potential of secondary metabolites of Streptomyces sp. and Trichoderma sp. on various production media on the percentage of S. litura larval attack on corn plants. The study was conducted using a completely randomized factorial design with the first factor being the types and combination of biological control agents used, namely Streptomyces sp. and Trichoderma sp. While the second factor is the type of propagation media used i.e glucose nitrate (GN) and potato dextrose agar (PDA). The results showed that the combination of Streptomyces sp. and Trichoderma sp. on PDA production media with a concentration ratio of 5:1 can increase the potential of secondary metabolites in suppressing the percentage of S. litura larval attack on corn plants by up to 10%.

IN VITRO SCREENING OF CELL WALL DEGRADING ENZYME PRODUCTIVITY FROM FUNGAL CULTURE FILTRATES ON DEPROTEINISED PLANT FLUID BY CUP PLATE ASSAY

The present study purpose is to evaluate the potentiality of the Deproteinised juice made from selected plants to induce the enzyme productivity by growing the fungi on it. It is because, in earlier findings, the DPJ was found potential in enhancing fungi and the plant growth when used as the medium. The internal factors are responsible in DPJ which induces plants and fungi growth. During the process of Green Crop Fractionation (GCF), the deproteinised (DPJ) obtained from tissues of cabbage, beet, lucerne (Alfalfa), carrot and Anathum (Dill) forages left after leaf protein extraction employed as a medium for the cultivation of mycelial biomass of Penicillium and Aspergillus fungi. The mycelial growth in vitro was compared with the glucose nitrate medium. The culture filtrates were used to screen different secreted hydrolytic or cell wall degrading enzymes.. The agar ‘cup‐plate’ diffusion technique has been applied to the quantitative determination of enzyme activity, principally to amylase, cellulase and protease. With all enzymes so far examined, the relationship between diameter of zone over a wide range secreted quantitatively was examined. All fungi grew well on DPJ in comparison to their growth on glucose nitrate (GN) medium. Comparatively with GN medium, lucerne DPJ was found having more mycelial cellular proliferation. When the fungi grown on different concentrations of substrates, enriched with carboxymethyl cellulose, casein and starch in deproteinised leaf extracts and GN medium, it was found that there was the enhancement in the mycelial dry weight grown on DPJ as compared with glucose nitrate medium. Penicillium showed more yield of enzyme activities especially of cellulases and amylases as compared to protease by cup plate method. There was enhancement of mycelial biomass when the concentrations of substrates increased from 1% to 2%, while there was no change in the activity of all enzymes by increasing the concentrations of substrates. Activities of the enzymes in vitro can be indicative of the pattern of organogenesis in callus cultures in further studies by fungal culture filtrates cultured on deproteinised fluid medium.