scholarly journals Potency of Dioscorea sansibarensis (Dioscoreaceae) Leaf Eluates on Callosobruchus chinensis, Linnaeus 1758 (Coleoptera: Bruchidae) in the Protection of Phaseolus vulgaris (Fabaceae)

2021 ◽  
Vol 47 (3) ◽  
pp. 1330-1337
Author(s):  
Godfrey Mauti

Post-harvest losses of stored Phaseolus vulgaris to the bean weevil Callosobruchus chinensis have reached levels of significant concern. Governments and health organisations propose the discovery of reliable,  healthy and biodegradable pesticides with higher selectivity and a broad spectrum. This study presents investigations on the activities of Dioscorea sansibarensis leaf extracts on the mortality of C. chinensis and reduction of their egg-laying ability. Laboratory experiments under Completely Randomized Design (CRD) were carried out to determine the mortality and anti-oviposition activity of the vacuum liquid chromatography (VLC) eluates of n-hexane (HE), chloroform (CE), ethyl acetate (EE), n-butanol (BE) and methanol (BE) at different concentrations. Bioassay data were subjected to nonparametric statistical analysis and a generalized linear model at p = 0.05. Statistical results showed that the VLC eluates had a mortality activity of 88.01% (R2 = 0.8801). Treatment by 0.025 g of HE and 0.075 g of CE had 9.60 and 11.50, respectively at p = 0.181. These mortality records were high as to 0.1 g of ME, 0.05 g of EE and 0.075 g of BE that recorded 8.55, 8.45 and 7.80, respectively. Treatments by 0.05 g of CE, 0.025 g of HE, 0.05 g of EE and the positive control recorded mortality of 10.50, 9.60, 8.45 and 8.35, respectively. The highest mortality was observed in the treatment by 0.075 g of HE and 0.1 g of HE with 12.85 and 13.70, respectively at p = 0.377. The VLC eluates had an anti-oviposition activity of 24.98% (R2 = 0.2498) on the C. chinensis. The generalized linear model reported Wald Chi-Square values of 4.363; p = 0.037, 0.711; p = 0.399, 9.125; p = 0.003, 4.363; p = 0.037 on the treatment by 0.025 g of CE, 0.05 g of EE, 0.075 g of BE and 0.1 g of ME, respectively. At p = 0.051, 0.1 g of CE and the positive control attained oviposition of 89.25 and 96.75 respectively. The study presents the first documentation of the lethal activity of D. sansibarensis on the C. chinensis pulse beetle. This could help in the development of Integrated Pest Management (IPM) and could help in the elimination or suppression of the infestation. Keywords: anti-oviposition, Callosobruchus chinensis, Dioscorea sansibarensis leaf, mortality, Phaseolus vulgaris, vacuum liquid chromatography (VLC) eluates.

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Godfrey O. Mauti ◽  
Peter F. Kasigwa ◽  
Joan J. E. Munissi ◽  
Justus M. Onguso

Callosobruchus chinensis causes damage to the Phaseolus vulgaris seeds. Traditionally, Dioscorea sansibarensis serves as a medicinal plant. Naturally, D. sansibarensis has toxins that protect against herbivores and the surrounding invasive plants in its natural habitat. Phytochemical analysis by thin-layer chromatography (TLC) and laboratory experiments was carried out to determine the activity of D. sansibarensis leaves, bulbils, and yams powders on antioviposition and inhibition of the F1 emergence of C. chinensis. Bioassay data were subjected to nonparametric (Kolmogorov–Smirnov) statistical analysis and a generalized linear model at P ≤ 0.05 . Statistically, the powders had an antioviposition activity of 34.3% (R2 = 0.343). A recommendable activity on antioviposition was displayed by the yams powder; treatment by 0.8 g of yams powder had a Wald Chi-Square value of 1.291, P = 0.26 . Inhibition of F1 emergence was significantly attained by the yams powder; the treatment by 0.6 g of yams powder had a Wald Chi-Square value of 7.72, P = 0.01 . Statistically, the bulbils powder displayed low antioviposition and inhibition of F1 emergence. Observations on the TLC exposed compounds with similar Rf values; saponin with an Rf value of 0.72 was portrayed in the leaves, bulbils, and yams. A terpenoid and a flavonoid with Rf values of 0.37 and 0.71, respectively, were observed in bulbils and yams but absent in leaves. A terpenoid with an Rf value of 0.49 was visualized in leaves and bulbils but not in the yams powder. The study concluded that the D. sansibarensis yams and leaves powders are viable for application by the farmers in the protection of stored legumes against attack by C. chinensis. However, there may be other diverse interests in other storage insects and other methods of phytochemical analysis that have not been investigated.


Linguistics ◽  
2015 ◽  
Vol 53 (3) ◽  
Author(s):  
Richard Wiese ◽  
Augustin Speyer

AbstractWords in German show several instances of a seemingly optional schwa-zero alternation, both in relation with inflected forms as well as in the final position of stems and simplex words, as inLarge-scale corpora are used as the main source of evidence for the verification or falsification of the hypothesis. A diverse set of nouns and adverbs involving schwa-zero alternations were studied in appropriate phrasal contexts, both from present-day Standard German and from Early New High German. Based on comprehensive corpus counts, these phrases are tested for the hypothesis of prosodic parallelism. A series of chi square tests and a generalized linear model with mixed effects demonstrate statistically that the prosodic shapes of the target word and its adjacent form are not independent of each other. The focus of the paper is on empirical evidence for


AGRICA ◽  
2019 ◽  
Vol 1 (2) ◽  
pp. 32-37
Author(s):  
Yustina M.S.W Puu ◽  
Hildegardis Nalti Nansi

Callosobruchus Chinensis is a pest that damages mung bean seeds in storage and causes damage to both the quality and quantity of seeds. This study aims to determine the effectiveness of neem leaf extracts in suppressing the development of the Callosobruchus Chinensis pest as one of the postharvest pests in the commodity green beans. This research conducted at the Laboratory of the Faculty of Agriculture, University of Flores, by using a Completely Randomized Design (CRD) with five treatments and three replications. The concentration of neem leaf extract treatment is 0 ml / l, 25 ml / l, 30 ml / l, 35 ml / l, and 40 ml / l. The results showed that the concentration of neem leaf extract 40 ml / l caused mortality of C. Chinensis imago as contact poison by 99% and nerve poison by 47%. While the effectiveness of the limb leaf extract on spawning activity was 86%.


Author(s):  
Shubhaisi Das ◽  
Sunanda Burman ◽  
Goutam Chandra

Background: The only remedy for up surging problem of antibiotic resistance is the discovery of antibacterial agents of natural origin. Objective: The present study was aimed at finding antibacterial potential of crude and solvent extracts of mature leaves of Plumeria pudica. Methods: Antibacterial activity of three different solvent extracts were evaluated in four human and four fish pathogenic bacteria by measuring the zone of inhibition and determining Minimum Inhibitory Concentration and Minimum Bactericidal Concentration values. Standard antibiotics were used as positive control. Preliminary phytochemical screening of most effective extract i.e., ethyl acetate extract, Fourier Transform Infra Red analysis and GC-MS analysis of the Thin Layer Chromatographic (TLC) fraction of ethyl acetate extract were done meticulously. All experiments were done thrice and analyzed statistically. Results: Crude leaf extracts and solvent extracts caused good inhibition of bacterial growth in all selected bacteria. Ethyl acetate extract showed highest inhibition zones in all tested strains with maximum inhibition (19.50±0.29 mm) in Escherichia coli (MTCC 739). MBC/MIC of the extracts indicated that all three solvent extracts were bactericidal. Preliminary phytochemical tests revealed the presence of tannins, steroids and alkaloids and FT-IR analysis revealed presence of many functional groups namely alcoholic, amide, amine salt and aldehyde groups. From the GC-MS analysis of TLC fraction of ethyl acetate extract five different bioactive compounds e.g., 2,4-ditert –butylphenyl 5-hydroxypentanoate, Oxalic acid; allyl nonyl ester, 7,9-Ditert-butyl-1-oxaspiro(4,5)deca-6,9-diene-2,8-dione, Dibutyl phthalate and 2,3,5,8-tetramethyl-decane were identified. Conclusion: Leaf extracts of P. pudica contain bioactive compounds that can be used as broad spectrum bactericidal agent.


2021 ◽  
pp. 1-16
Author(s):  
Erika-Alejandra Salinas-Peña ◽  
Martha Mendoza-Rodríguez ◽  
Claudia Velázquez-González ◽  
Carlo Eduardo Medina-Solis ◽  
América Patricia Pontigo-Loyola ◽  
...  

BACKGROUND: The Mexican serviceberry, Malacomeles denticulata, have been used as a successful oral therapy by Mexican communities without enough scientific support. OBJECTIVE: To evaluate the M. denticulata extracts with selective antibacterial properties over dental biofilm bacteria. METHODS: Fruit, Leaf, and Stem of M. denticulata extracts were evaluated with micro-broth dilution method using ATCC bacteria. OD600 values had compared against each positive control (T-student-test). Anaerobically viability had confirmed by Colony-Forming-Units. Thin-Layer-Chromatography was used to identify the number of compounds and phytochemicals to identify secondary metabolites of the selected extracts. RESULTS: Streptococcus mutans showed Minimum-Bactericidal-Concentrations_(MBC) at 30 mg/mL to Fruit, Leaf, and Stem extracts. Periodontal-pathogens Aggregatibacter actinomycetemcomitans serotype b_(MBC = 30 mg/mL_p <  0.01); Fusobacterium nucleatum subsp. nucleatum_(MBC = 30 mg/mL_p<0.001); Parvimonas micra_(MBC = 15 mg/mL_NS); Porphyromonas gingivalis_(MBC = 30 mg/mL_NS); and Prevotella intermedia_(MBC = 3.75 mg/mL_NS) presented higher sensitivity to Leaf-Methanol, than the primary colonizers. Phytochemicals showed positive results to anthraquinones, coumarins, flavonoids, saponins, saponins steroids/triterpenoids, steroids/triterpenes, and tannins/phenols. CONCLUSION: We suggest the natural extracts of fruit and leaf of the Mexican serviceberry for the preventive use over the oral cariogenic or periodontal biofilm species, by their selective antibacterial properties against pathogenic species evaluated in-vitro, and due to the presence of antibacterial secondary metabolites identified as flavonoids and saponins of M. denticulata leaf extracts.


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