Asha Sinha

Variation of Soil Mycoflora in Decomposition of Rice Stubble from Rice-wheat Cropping System

The colonization pattern and extent of decay produced in paddy stubble by soil inhabiting mycoflora were done by using nylon net bag technique. Among the three methods used for isolation of fungi, dilution plate technique recorded the highest number of fungi followed by damp chamber and direct observation method. Nutrient availability and climatic conditions (temperature, humidity and rainfall) influenced the occurrence and colonization pattern of fungi. Maximum fungal population was recorded in October (48.99 × 104/g dry litter) and minimum in May (11.41 × 104/g dry litter). Distribution of Deuteromyeetous fungi was more in comparison to Zygomycetes, oomyeetes and aseomyeetes. In the early stage of decomposition Mucor racemosus, Rhizopus nigricans, Chaetomium globosum and Gliocladium species were found primarly whereas at later stages of decomposition preponderance of Aspergillus candidus, Torula graminis, Cladosporiun dadosporioides and Aspergillus luchuensis was recorded.

Production of Soluble Crude Protein Using Cellulolytic Fungi on Rice Stubble as Substrate under Waste Program Management

The investigation was undertaken to enhance the decomposition process by pre-treatment of rice stubble, having higher concentration of lignin. Air-dried rice stubble was treated with 1.8 liter of 1% NaOH and autoclaved. Six cellulolytic fungi, Trichoderma harzianum, Penicillium citrinum, Cumularía lunata, Aspergillus flavus and Alternaría alternala were grown in basal synthetic medium along with delignified riee-residue as carbon source for production of soluble crude protein. Though the loss of cellulose has been observed by all of them but having a considerable status in the presence of T. harzianum and T. harzianum yielded highest percentage of crude protein (27.99%) with biomass of 375 mg, whereas the lowest protein value (17.91%) was recorded in ease of A. niger with biomass of 422 mg. Among the imperfect fungi, T. harzianum was the most potent. Effects of incubation period and nitrogen sources on soluble crude protein production by T. harzianum were also undertaken in this study. Fifth day of incubation period and potassium nitrate as nitrogen source among other nitrogen sources was found most appropriate for soluble crude protein production by the mentioned organism.

Effect of Temperature on Production of Endoglucanase and Xylanase from Some Green Manure Fungal Decomposers

Among the various microorganisms reported for their capabilities of cellulases and xylanases production, fungi are the most potent producers. This study reports the production of xylanolytic and cellulolytic enzymes by potential decomposing fungal isolates using a cheap medium containing green manure substrate and chemically defined basal medium under solid-state culture. A number of decomposing fungi were screened for cellulolytic and xylanolytic potential. The enzyme production with purified carboxy methyl cellulose (CMC) and birch wood xylan was studied and found to be promising. Aspergillus niger produced the highest amount of endoglucanase and xylanase viz., 3.635 U mg -1 protein min -1 and 2498.20 U mg -1 protein min -1 , respectively at 25°C. Growth and enzyme production was affected by the alterations in temperature. Highest production of endoglucanse and xylanase were noted at 25°C and 30°C.

Ecological Biodiversity Measurement of Seed Mycoflora Contamination of Freshly Harvested in Maize Growing Zone-II

Maize is considered third most important cereal crops in the world. In our study the seed mycoflora of freshly harvested maize of zone-II were isolated by Agar plate method (APM) and Blotter plate method (BPM). A total of 9 genera i.e. Aspergillus flavus, A. niger, Bipolaris maydis, Curvularia lunata, Fusarium verticilioides, Penicillium notatum, P. expensum, Rhizopus stolonifer, and Rhizoctonia solani were isolated by standard Agar plate method and 10 fungal genera, i.e. Alternaria alternata, Aspergillus flavus, A. niger, Bipolaris maydis, Curvularia lunata, Fusarium verticilioides, Macrophomina phaseolina, Penicillium notatum, Rhizopus stolonifer, and Rhizoctonia solani by blotter plate method. On the basis of density, frequency and abundance, Aspergillus flavus, A. niger and Rhizopus stolonifer were found as dominate and taken for detail study. The seed lot of this zone is three categories i.e. Original (OS), Partial discolour (PDS) and Discolour seed (DS). Maximum important value index (IVI), Simpson index of dominance (D), Shannon-Weaver index of diversity (H) and Evenness (E) of Aspergillus flavus OS (86.657%, 0.0834, 0.359, 0.184), PDS (63.827%, 0.0453, 0.329, 0.150) and DS (83.467%, 0.0774, 0.356, 0.183) were contributed. In Blotter plate method, highest density of A. niger OS (5.850), A. flavus PDS (4.500), DS (5.225) were recorded. Maximum frequency showed by A. flavus (100.000%) in all categories. The abundance of A. flavus OS (0.350), PDS (0.342), DS (0.407) were recorded. Relative density maximum recorded in A. niger OS (26.401%), A. flavus PDS (19.268%) and DS (26.381%). Relative frequency (RF) and relative abundance (RA) highest were found in A. flavus OS (24.691%, 35.009%), PDS (23.256%, 34.221%) and DS (23.810%, 40.661%). Maximum IVI, Simpson index of dominance, Shannon-Weaver index of diversity and evenness contributed A. flavus OS (80.912%, 0.0727, 0.353, 0.170), PDS (76.744%, 0.0654, 0.349, 0.159) and DS (90.852 %, 0.0917, 0.362, 0.174). These species are some of the common on the maize during storage and spoil the grains.