Vermicomposting of coirpith with cowdung by Eudrilus eugeniae Kinberg and its efficacy on the growth of Cyamopsis tetragonaloba (L) Taub

AbstractIn view of the growing awareness about ecofriendly organic farming and biotechnology, coirpith and cowdung natural sources were used to produce vermicompost which showed enhanced growth promoting effect in the crop Cyamopsis tetragonaloba. Initially, neutral detergent fibre, acid detergent fibre, lignin, cellulose and hemicellulose contents were determined in three different grades of coirpith and in cowdung. Vermicompost was prepared using the earthworm Eudrilus eugeniae with 60days maintenance. During composting N, P, K and C contents were estimated in vermicompost as well as in control compost. N, P and K values were highly increased in vermicompost. C:N was dramatically decreased in vermicomposting during the experimental period. Vermicompost enhanced the growth of tested C. tetragonaloba crop. Vermicompost treated plants were taller by 9cm when compared with the control plant. The use of Vermicompost also led to a marked increase in plant biomass

Isolation and Characterization of Bacteria from the Gut of Bombyx mori that Degrade Cellulose, Xylan, Pectin and Starch and Their Impact on Digestion

Bombyx mori L. (Lepidoptera: Bombycidae) have been domesticated and widely used for silk production. It feeds on mulberry leaves. Mulberry leaves are mainly composed of pectin, xylan, cellulose and starch. Some of the digestive enzymes that degrade these carbohydrates might be produced by gut bacteria. Eleven isolates were obtained from the digestive tract of B. mori, including the Gram positive Bacillus circulans and Gram negative Proteus vulgaris, Klebsiella pneumoniae, Escherichia coli, Citrobacter freundii, Serratia liquefaciens, Enterobacter sp., Pseudomonas fluorescens, P. aeruginosa, Aeromonas sp., and Erwinia sp.. Three of these isolates, P. vulgaris, K. pneumoniae, C. freundii, were cellulolytic and xylanolytic, P. fluorescens and Erwinia sp., were pectinolytic and K. pneumoniae degraded starch. Aeromonas sp. was able to utilize the CMcellulose and xylan. S. liquefaciens was able to utilize three polysaccharides including CMcellulose, xylan and pectin. B. circulans was able to utilize all four polysaccharides with different efficacy. The gut of B. mori has an alkaline pH and all of the isolated bacterial strains were found to grow and degrade polysaccharides at alkaline pH. The number of cellulolytic bacteria increases with each instar

Phytochemical residue profiles in rice grains fumigated with essential oils for the control of rice weevil

<div><p>In the present study, we investigated the fumigant potential of five edible essential oils (EOs) against <i>Sitophilus oryzae</i> and their phytochemical residues in treated grains. Among the tested EOs, peppermint oil proved significantly effective (P ≤ 0.05) on <i>S</i>.<i>oryzae</i> at 400 μl/L air concentration, inducing 83 and 100% mortalities in with-food and without-food conditions respectively over 72 h exposure. In addition, it was also observed that the binary mixtures of peppermint + lemon oil (1:1 ratio) produced an equivalent effect to that of peppermint oil alone treatments. The phytochemical residue analysis by GC-MS revealed the presence of six compounds upon 72 h exposure to EOs. Further, the analysis of physico-chemical properties of the compounds indicated a positive correlation between polar surface area (PSA) and its residual nature. The residue levels of eugenol were significantly elevated corresponding to its high PSA value (29) in clove and cinnamon oils. On the other hand, the compounds with zero PSA value imparted very less or no (D-Limonene, caryophyllene, pinene and terpinolene) residues in treated grains. With respect to the most active peppermint oil, L-menthone, menthyl acetate and eucalyptol residues were at 67, 41 and 23% levels respectively. The outcome of the present study indicate the peppermint oil as a potent fumigant against <i>S</i>. <i>oryzae</i>, and although the residues of phytochemicals in treated grains is higher; they belong to the generally recognised as safe (GRAS) status leaving no harmful effect.</p></div

Mortality of <i>S</i>. <i>oryzae</i> adults exposed to selected four phytocompounds at different concentrations and times under with and without-food conditions.

<p>Mortality of <i>S</i>. <i>oryzae</i> adults exposed to selected four phytocompounds at different concentrations and times under with and without-food conditions.</p

Phytochemical residues detected in essential oils fumigated rice grains.

<p>Phytochemical residues detected in essential oils fumigated rice grains.</p

Comparison of GC-MS chromatogram of methanolic extract of fumigated rice grains with standard essential oils.

<p>Comparison of GC-MS chromatogram of methanolic extract of fumigated rice grains with standard essential oils.</p

Mortality of <i>S</i>. <i>oryzae</i> adults exposed to five edible essential oils at different concentrations and times under without-food conditions.

<p>Mortality of <i>S</i>. <i>oryzae</i> adults exposed to five edible essential oils at different concentrations and times under without-food conditions.</p

Relative concentrations of phytochemicals estimated from five edible essential oils.

<p>Relative concentrations of phytochemicals estimated from five edible essential oils.</p